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Misdiagnosis of Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy
Abstract
Diagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) has major implications for the management of patients and their first-degree relatives. Diagnosis is based on a set of criteria proposed by the International Task Force for Cardiomyopathies. We report our experience in providing a re-evaluation for patients who previously have been diagnosed with ARVD/C.
We studied 89 patients who requested a re-evaluation for diagnosis of ARVD/C at our center. Each of these patients had been diagnosed with ARVD/C at their initial evaluation. Each patient was re-evaluated with clinical history, physical examination, and noninvasive testing at our center. Invasive testing, which included electrophysiologic testing, right ventricular angiography, and endomyocardial biopsy, was performed when clinically indicated. Sixty (92%) of the 65 patients who had undergone magnetic resonance imaging (MRI) at an outside institution were reported to have an abnormal MRI consistent with ARVD/C. Among these patients, the only abnormality identified was the qualitative finding of intramyocardial fat/wall thinning in 46 patients. On re-evaluation, these qualitative findings were not confirmed. None of these 46 patients ultimately were diagnosed with ARVD/C. Among the entire patient group, only 24 (27%) of the 89 patients met the Task Force criteria for ARVD/C.
This study demonstrates that the high frequency of "misdiagnosis" of ARVD/C is due to over-reliance on the presence of intramyocardial fat/wall thinning on MRI, incomplete diagnostic testing, and lack of awareness of the Task Force criteria. Diagnosis of ARVD/C cannot rely solely upon qualitative features on MRI.
... Based on study reports, by detecting microaneurysm, wall bulging, and fibrous tissue, and calculating the volume of right and left ventricles and the ejection fraction and comparing them with echocardiography results, magnetic resonance imaging (MRI) can have an efficient role in diagnosing ARVD and related pathologies. However, detection of intramyocardial fat in the right ventricle by MRI is unreliable, and the contact of pericardial fat with a thin right ventricle wall leads to misdiagnosis of fat tissue infiltration in the heart [11]. ...
... In this cross-sectional study, 39 patients with ARVD that were diagnosed based on Task Force criteria [11] and were candidates for ablation at the Tehran Shahid Rajaei Heart Centre during 2017 to 2018 were investigated. This study was approved by the Iran University of Medical Sciences ethical committee (ethical code: 11-1395). ...
... Based on a study using MRI on 41 patients suspected of having ARVD, the disease was definitively confirmed only in 60% of them [11]. Possible reasons for different interpretations of imaging by other techniques may be that this disease is an uncommon disorder and requires special diagnostic protocols for desired evaluation. ...
Arrhythmogenic right ventricular dysplasia (ARVD) is an abnormality in the right side of the heart that may lead to sudden death. The study aims to compare cardiac MRI (magnetic resonance imaging findings) with echocardiography in patients with ARVD. For the cross-sectional study, patients with ARVD that were diagnosed using Task Force criteria were included, and their cardiac MRI findings were evaluated. Additionally, the right ventricle was divided into three levels—basal, middle, and apical—and each of them was also subdivided into three secondary segments. Gadolinium enhancement was evaluated in each segment. Overall, 39 patients were studied. Thirty-one patients (81%) were men. The average age of female and male patients was 37.8 ± 4.6 and 32.48 ± 5.8, respectively. The average ejection fraction found was 43 ± 9.4 and 42.8 ± 8.5% by MRI and echocardiography, respectively. Additionally, 46 and 35.8% of the patients had hypokinesia in the right ventricle, found based on MRI and echocardiography, respectively. The right ventricular aneurysm was found in 20.5 and 5.1% of patients based on MRI and echocardiography, respectively. The cardiac MRI managed to diagnose some cases which echocardiography was not able to detect. Thus, MRI plays an important role in presenting diagnostic data for the management of patients with ARVD and also making the diagnosis in suspicious patients definitive.
... Physiological conditions as well as right ventricular abnormalities can cause suspicion of ARVC on cardiac MRI [68,[84][85][86][87]. Inaccurate MRI interpretation can have serious repercussions, including the need for an internal cardiac defibrillator, antiarrhythmic medication with sotalol and amiodarone, and the probability of a poor prognosis. ...
... The radiologist interpreting images of suspected ARVC should have sufficient experience, considering the fact that in early stages of the disease the differential diagnosis must be made with other diseases that have similar characteristics [84,103]. ...
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare disease in which the right ventricular myocardium is replaced by islands of fibro-adipose tissue. Therefore, ventricular re-entry circuits can occur, predisposing the patient to ventricular tachyarrhythmias, as well as dilation of the right ventricle that eventually leads to heart failure. Although it is a rare disease with low prevalence in Europe and the United States, many patients are addressed disproportionately for cardiac magnetic resonance imaging (MRI). The most severe consequence of this condition is sudden cardiac death at a young age due to untreated cardiac arrhythmias. The purpose of this paper is to revise the magnetic resonance characteristics of ARVC, including the segmental contraction abnormalities, fatty tissue replacement, decrease of the ejection fraction, and the global RV dilation. Herein, we also present several recent improvements of the 2010 Task Force criteria that are not included within the ARVC diagnosis guidelines. In our opinion, these features will be considered in a future Task Force Consensus.
... This field of enquiry can learn perhaps from similar research in other conditions, such as arrhythmogenic right ventricular cardiomyopathy (ARVC). Bomma et al. studied 89 patients who had been diagnosed with ARVC but requested a second opinion at a large academic center with specific expertise [22]. Amongst 65 patients reported to have abnormal CMR, in 46/65 the only abnormality reported was intra-myocardial fat and/or wall thinning. ...
... On reevaluation at the expert academic center none of these CMR findings were confirmed and none of these 46 patients ultimately were diagnosed with ARVC. Many of these patients had already received ICDs for the primary prevention of sudden cardiac death [22]. This study led to a thoughtful re-evaluation of the role of CMR in the diagnosis of ARVC. ...
Cardiac sarcoidosis (CS) is an increasingly recognized condition, but cardiac magnetic resonance (CMR) image interpretation in these patients may be challenging as findings are often non-specific. The main objective of this study was to investigate the inter-reader agreement for the overall interpretation of CMR for the diagnosis of CS in an experienced reference center and investigate factors that may lead to discrepancies between readers. Consecutive patients undergoing CMR imaging to investigate for CS were included. CMR images were independently reviewed by two readers, blinded to all clinical, imaging and demographic information. The readers classified each scan as “consistent with cardiac sarcoidosis”, “not consistent with cardiac sarcoidosis” or “indeterminate”. Inter-reader agreement was assessed using κ-statistics. When there was disagreement on the overall interpretation, a third reader reviewed the images. Also, two readers independently commented on the presence of edema, presence of LGE (both ventricles) and quantified the extent of left ventricular LGE. 87 patients (43 women, mean age 54.3 ± 12.2 years) were included in the study. There was agreement regarding the overall interpretation in 72 of 87 (83%) CMR scans. The κ value was 0.64, indicating moderate agreement. There was similar moderate agreement in the interpretation of LGE parameters. In an experienced referral center, we found moderate agreement between readers in the interpretation of CMR in patients with suspected CS. Physicians should be aware of this inter-observer variability in interpretation of CMR studies in patients with suspected CS.
... Congenital abnormalities involving the right ventricle and cardiac disorders such as viral or inflammatory myocarditis have been suggested as non-genetic etiologies of ARVD. Four theories have also been proposed over time to explain the cause of ARVD or as environmental conditions facilitating genetic expression of ARVD: (a) disontogenetic theory [8,58]; (b) degenerative theory [8,59]; (c) inflammatory theory [7,33,60,61]; (d) apoptotic theory [62,63]; and (e) myocyte trans-differentiation theory [64]. ...
... Apoptotic theory suggest ARVD results from apoptosis explained by the presence of cysteine protein required for apoptosis observed in diseases RV myocardium of six ARVD patients but absent in normal patients [62,63]. Finally, the transdifferentiation theory proposed that ARVD results from myocardial cells changing from muscle to fatty tissues underpinned by the finding that one ARVD patient has transitional cells interfacing myocardium and fatty tissues expressing desmin, a characteristic of muscle tissues and vimentin, found only in adipocytes [64]. ...
... In addition, qualitative analysis of CMR data resulted in ARVC over-diagnosis. 45 The TFC were revised in 2010 to improve diagnostic sensitivity, albeit in the absence of a gold-standard. Revised TFC included genetic criteria, new electrical parameters and quantification of cardiac imaging. 1 This led to increased ARVC diagnosis in familial disease and for carriers of desmosomal mutations, but reduced numbers of patients fulfilling CMR criteria, creating a subgroup who no longer satisfied TFC and have subsequently had their ARVC diagnosis removed. ...
... Original TFC for imaging, including myocardial fatty infiltration, were qualitative and resulted in over-diagnosis. 44,45 When the TFC were revised, imaging parameters were quantified and CMR assessment of myocardial fat was no longer recommended ( Table 2). 1 Classical disease causes RV regional wall motion abnormalities (RWMA) with ...
Our understanding of arrhythmogenic right ventricular cardiomyopathy (ARVC) has advanced considerably over the past 30- 40 years. This is an inherited cardiomyopathy with complicated genetic inheritance and variable penetrance. Desmosomal dysfunction underlies most cases, and appreciating this pathophysiology has contributed to patient management, particularly with respect to exercise restriction to reduce disease progression. The diagnosis is made according to a series of Task Force Criteria, and subsequent management is guided by expert consensus in the absence of comparative data. ARVC is associated with sudden cardiac death (SCD), particularly in young athletic individuals who unknowingly harbour the condition. Risk stratification is important to guide implantable cardioverter- defibrillator use and reduce SCD. Residual gaps in our understanding, particularly surrounding incomplete penetrance, the underlying pathophysiology and risk stratification, are being targeted by collaborative efforts, large registries, prospective studies and translational research.
... One report on the rate of misdiagnosis for AC identified that only 24 of 89 (27%) people referred to a tertiary center met the diagnostic criteria established at the time. 9 AC is known to occur throughout the world. It has historically had a high prevalence in Northeastern Italy, where a systematic investigation of the causes of SCD in the young and a universal preparticipation screening strategy have identified affected individuals more commonly than in other countries. ...
... 4,19 Genotype-phenotype correlation studies have demonstrated that the disease can have a phenotypic spectrum much wider than previously thought. 9,10,25 The pathologic features range from grossly normal hearts at one end, in whom only a careful histopathologic investigation can reveal AC features in one or both ventricles, to hearts with massive biventricular disease involvement. Recently, an isolated, nonischemic LV fibrofatty scar, as seen either at postmortem examination or by post-contrast cardiac magnetic resonance (MR) sequences, has been reported to be a not uncommon myocardial substrate of life-threatening ventricular arrhythmias and SCD in young people and athletes. ...
Arrhythmogenic cardiomyopathy is an inherited heart muscle disorder, predisposing to sudden cardiac death, particularly in young patients and athletes. Pathological features include loss of myocytes and fibrofatty replacement of right ventricular myocardium; biventricular involvement is often observed. It is a cell-to-cell junction cardiomyopathy, typically caused by genetically determined abnormalities of cardiac desmosomes, which leads to detachment of myocytes and alteration of intracellular signal transduction. The diagnosis of arrhythmogenic cardiomyopathy does not rely on a single gold standard test but is achieved using a scoring system, which encompasses familial and genetic factors, ECG abnormalities, arrhythmias, and structural/functional ventricular alterations. The main goal of treatment is the prevention of sudden cardiac death. Implantable cardioverter defibrillator is the only proven lifesaving therapy; however, it is associated with significant morbidity because of device-related complications and inappropriate implantable cardioverter defibrillator interventions. Selection of patients who are the best candidates for implantable cardioverter defibrillator implantation is one of the most challenging issues in the clinical management.
... Previous studies have also described CMR as a contributor to misdiagnosis. 10,13,17,18 Our study confirms and expands these findings in a large cohort of patients and shows that these issues have persisted despite the introduction of specific, quantifiable CMR metrics in the revised 2010 TFC. Our study reveals 2 major types of errors in the interpretation of CMR. ...
Background:
The diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) is challenging due to nonspecific clinical findings and lack of conclusive answers from genetic testing (i.e., an ARVC-related variant is neither necessary nor sufficient for diagnosis). Despite the revised 2010 Task Force criteria, patients are still misdiagnosed with ARVC.
Objective:
In patients referred for ARVC, we sought to identify the clinical characteristics and diagnostic confounders for those patients in whom ARVC was ultimately ruled out.
Methods:
Patients who were referred to our center with previously diagnosed or suspected ARVC (1/2011-9/2019, n = 726) were included in this analysis.
Results:
Among 726 patients, ARVC was ruled out in 365 (50.3%). The most common presenting symptoms in ruled-out patients were palpitations (38.1%), ventricular arrhythmias (17.0%), and chest pain (14.5%). Based on outside evaluation, 23.8% of these patients had received implantable cardioverter-defibrillators (ICDs), and device extraction was recommended in 9.0% after re-evaluation. An additional 5.5% had received ICD recommendations, all of which were reversed on re-evaluation. The most frequent final diagnoses were idiopathic premature ventricular contractions/ventricular tachycardia/ventricular fibrillation (46.6%), absence of disease (19.2%), and noncardiac presyncope/syncope (17.5%). The most common contributor to diagnostic error was cardiac magnetic resonance imaging (CMR), including mistaken right ventricular wall motion abnormalities (33.2%) and nonspecific fat (12.1%).
Conclusion:
False suspicion or misdiagnosis was found in the majority of patients referred for ARVC, resulting in inappropriate ICD implantation or recommendation in 14.5% of these patients. Misdiagnosis or false suspicion was most commonly due to misinterpretation of CMR.
... Such a semiautomatic approach could lead to a large reduction in inter-observer variability. This is not only interesting for specialized tertiary ARVC centers, but even more for less experienced centers, since CMR misinterpretations are an important cause of over-diagnosis in ARVC and only 27% of people referred to a tertiary center with a suspected ARVC diagnosis finally meet diagnostic criteria for ARVC [44]. Our work shows that our previously developed deep learning segmentation method is able to fulfill a diagnostic purpose by simplifying accurate calculation of functional and volumetric measurements for the CMR TFC, showing opportunities to facilitate and improve individual patients health. ...
Background
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is diagnosed according to the Task Force Criteria (TFC) in which cardiovascular magnetic resonance (CMR) imaging plays an important role. Our study aims to apply an automatic deep learning-based segmentation for right and left ventricular CMR assessment and evaluate this approach for classification of the CMR TFC.
Methods
We included 227 subjects suspected of ARVC who underwent CMR. Subjects were classified into (1) ARVC patients fulfilling TFC; (2) at-risk family members; and (3) controls. To perform automatic segmentation, a Bayesian Dilated Residual Neural Network was trained and tested. Performance of automatic versus manual segmentation was assessed using Dice-coefficient and Hausdorff distance. Since automatic segmentation is most challenging in basal slices, manual correction of the automatic segmentation in the most basal slice was simulated (automatic −basal ). CMR TFC calculated using manual and automatic −basal segmentation were compared using Cohen’s Kappa (κ).
Results
Automatic segmentation was trained on CMRs of 70 subjects (39.6 ± 18.1 years, 47% female) and tested on 157 subjects (36.9 ± 17.6 years, 59% female). Dice-coefficient and Hausdorff distance showed good agreement between manual and automatic segmentations (≥ 0.89 and ≤ 10.6 mm, respectively) which further improved after simulated correction of the most basal slice (≥ 0.92 and ≤ 9.2 mm, p < 0.001). Pearson correlation of volumetric and functional CMR measurements was good to excellent (automatic ( r = 0.78–0.99, p < 0.001) and automatic −basal ( r = 0.88–0.99, p < 0.001) measurements). CMR TFC classification using automatic −basal segmentations was comparable to manual segmentations (κ 0.98 ± 0.02) with comparable diagnostic performance.
Conclusions
Combining automatic segmentation of CMRs with correction of the most basal slice results in accurate CMR TFC classification of subjects suspected of ARVC.
Graphical abstract
... [14][15][16][17] However, imaging evaluation is far from being specific for ARVC. Indeed, Bomma et al 18 reported that up to 73% of presumed patients with ARVC were misdiagnosed, based on CMR misinterpretation. Moreover, the agreement between echocardiography and CMR is low, thus reducing the degree of confidence in the results. ...
Background
Endomyocardial biopsy (EMB) is part of 2010 Task Force Criteria (TFC) for arrhythmogenic right ventricular cardiomyopathy (ARVC). However, its usage has been curtailed because of its low presumed diagnostic yield, and it is now a poorly used tool. This study aims to analyze the contribution of EMB to the final diagnosis of ARVC.
Methods and Results
We included 104 consecutive patients evaluated for a suspicion of ARVC, who were referred for EMB. Patients with suspected left dominant pattern were excluded from the primary analysis. Subjects were initially stratified according to TFC without considering EMB. After EMB, patients were reclassified accordingly, and the reclassification rate was calculated. EMB yielded a diagnostic finding in 92 patients (85.5%). After including EMB evaluation, 20 (43%) more patients “at risk” received a definite diagnosis of ARVC. Overall, 59 patients received a definite diagnosis of ARVC, 34% only after EMB. EMB appeared to be the better‐performing exam with respect to the final diagnosis (β, 2.2; area uder the curve, 0.73; P <0.05). The reclassification improvement after EMB measured 28%. TFC score increased from 3.5±1.3 to 4.3±1.4 ( P <0.001). Notably, active inflammation was present in 6 (10%) patients. Minor complications were reported in only 2% of the cohort. In patients with suspected left‐dominant disease, conventional TFC performed poorly.
Conclusions
Electroanatomic voltage mapping–guided EMB was safe and yielded an optimal diagnostic yield. It allowed upgrading of the diagnosis of nearly one‐third of the patients considered “at risk.” Classical TFC without EMB performed poorly in patients with the left dominant form of ARVC.
... Today, delayed enhancement with magnetic resonance imaging (de-MRI) is considered a main tool for tissue characterisation, even though in patients with very early ARVD/C disease, subepicardial scar tissue is not detectable using current de-MRI High-density mapping = These catheters' features enable the detection of very small fragmented signals (< 0.5 mV and just above the noise amplitude). Through high-density bipolar mapping, a normal myocardium is defined as a tissue with a signal amplitude > 1. 5 imaging techniques; the phenotypic diagnosis of ARVD/C relies, in vivo, on histopathological demonstration of fibrofatty replacements through endomyocardial biopsy (EMB) [14][15][16][17]. Early in the 2000s, the EAM (by means of the CARTO™ system) was shown to accurately identify the location and extent of the pathological substrate of ARVC/D via detection of endocardial bipolar low-voltage regions, reflecting RV fibrofatty replacement and/or atrophy [18]. ...
Three-dimensional (3D) reconstruction by means of electroanatomic mapping (EAM) systems, allows for the understanding of the mechanism of focal or re-entrant arrhythmic circuits along with pacing techniques. However, besides this conventional use, EAM may offer helpful anatomical and functional information. Data regarding electromechanical scar detection in ischaemic (and nonischaemic) cardiomyopathy are mostly consolidated, while emerging results are becoming available in contexts such as arrhythmogenic right ventricular dysplasia (ARVC/D) definition and Brugada syndrome. As part of an invasive procedure, EAM has not yet been widely adopted as a stand-alone tool in the diagnostic path. We aim to review the current literature regarding the use of 3D EAM systems for right ventricle (RV) functional characterisation beyond the definition of arrhythmia.
... The diagnosis of inherited ACM is difficult because of the absence of unique diagnostic criteria and its variable expressivity (ie, RV dominant, biventricular, LV dominant). Bomma et al 17 showed that up to 73% of patients with presumed ARVC referred to their specialized center had the diagnosis ruled out after reevaluation. The authors attributed part of the high frequency of misdiagnosis to an overreliance on CMR findings. ...
Arrhythmogenic right ventricular cardiomyopathy was first described as a right ventricular disease that is an important cause of death in young adults. However, with the advent of advanced imaging, arrhythmogenic right ventricular cardiomyopathy has been found to commonly have biventricular involvement, and a small portion of patients have left ventricular–dominant forms. On the other hand, a number of primarily left ventricular disease such as sarcoid and myocarditis can be arrhythmogenic and have right ventricular involvement. A few recent publications on arrhythmogenic right ventricular cardiomyopathy cohorts have average left ventricular functions that are comparable to sarcoid or myocarditis cohorts. We review the current literature and compare these cohorts of patients, and call for left ventricular functional criteria for arrhythmogenic right ventricular cardiomyopathy as inherited arrhythmogenic cardiomyopathy.
... Although the TFC are a crucial tool for ARVC diagnosis, their complexity renders ARVC diagnosis prone to misinterpretation, hence leading to misdiagnosis. This was already shown by Bomma et al., 16 demonstrating that 73% of presumed ARVC patients were misdiagnosed, most commonly based on CMR misinterpretation. In our study, in which CMRs were overread by two blinded radiologists and final diagnosis was determined by a robust expert panel, 11% false negatives and 14% false positives occurred. ...
Aims:
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is diagnosed by a complex set of clinical tests as per 2010 Task Force Criteria (TFC). Avoiding misdiagnosis is crucial to prevent sudden cardiac death as well as unnecessary implantable cardioverter-defibrillator implantations. This study aims to validate the overall performance of the TFC in a real-world cohort of patients referred for ARVC evaluation.
Methods and results:
We included patients consecutively referred to our centres for ARVC evaluation. Patients were diagnosed by consensus of three independent clinical experts. Using this as a reference standard, diagnostic performance was measured for each individual criterion as well as the overall TFC classification. Of 407 evaluated patients (age 38 ± 17 years, 51% male), the expert panel diagnosed 66 (16%) with ARVC. The clinically observed TFC was false negative in 7/66 (11%) patients and false positive in 10/69 (14%) patients. Idiopathic outflow tract ventricular tachycardia was the most common alternative diagnosis. While the TFC performed well overall (sensitivity and specificity 92%), signal-averaged electrocardiogram (SAECG, P = 0.43), and several family history criteria (P ≥ 0.17) failed to discriminate. Eliminating these criteria reduced false positives without increasing false negatives (net reclassification improvement 4.3%, P = 0.019). Furthermore, all ARVC patients met at least one electrocardiogram (ECG) or arrhythmia criterion (sensitivity 100%).
Conclusion:
The TFC perform well but are complex and can lead to misdiagnosis. Simplification by eliminating SAECG and several family history criteria improves diagnostic accuracy. Arrhythmogenic right ventricular cardiomyopathy can be ruled out using ECG and arrhythmia criteria alone, hence these tests may serve as a first-line screening strategy among at-risk individuals.
... However, these parameters have low sensitivity and specificity for the diagnosis of ARVC 35,36 and significant interobserver variability in the interpretation of segmental contraction analysis of the RV free wall has been reported. [37][38][39] Tissue characterization findings by CMR (fibrosis, fatty infiltration, and fibrofatty scar) were not included in the 2010 ITF criteria because of limited experience, difficulty in the interpretation, and low specificity. 10 However, recent studies demonstrated the utility of combined regional wall motion assessment and tissue characterization by CMR for the diagnosis of ARVC. 4 The best accuracy (98%) was present when wall motion alterations and pre-/post-contrast signal abnormalities [including LV fat infiltration and late gadolinium enhancement (LGE)] were considered together. ...
... AC is generally characterized by impairment of ventricular systolic function, prominent ventricular arrhythmias, and fibrofatty myocardial replacement and has been linked to a number of genetic mutations, most of which induce desmosomal dysfunction. 1 AC occurs with an estimated population frequency between 1:1000 and 1:5000, though most clinicians who specialize in AC tend to believe the prevalence is closer to 1:5000. 1 This discrepancy is likely due to the frequent misdiagnosis of AC, an artefact of an over-reliance on MRI observation of intramyocardial fat/wall thinning, incomplete diagnostic testing, and an overall lack of awareness. 2 An alternative to these imperfect diagnostics is genetic testing. AC's high heritability, 1 and recent technological progress in genome sequencing 3 creates the potential for genetic diagnosis of AC as an alternative to these otherwise error-prone diagnostic tools. ...
... 11) Non-pathological wall motion disorders are common; some are due to tethering of the free wall by the moderator band, and can easily be mistaken for pathological regional wall motion contraction, particularly with unexperienced or biased readers. [12][13][14] Therefore, the presence of isolated RV dyskinesia should be accompanied by clinical and follow-up data to ascertain whether this is pathological finding and part of a spectrum of a progressive disease. While intramyocardial and RV free wall fat imaging is still performed, its role should be limited to avoid over calling. ...
BACKGROUND: The 2010 revised Task Force criteria for the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) provided guidance for the classification of patients as definitive, borderline or possible ARVC. However, many patients with clinical suspicion for ARVC have isolated RV dyskinetic segments only and partly meet cardiac magnetic resonance (CMR) imaging criteria. This subgroup of patients and the implication of this imaging finding remain not well defined.
METHODS: There were 65 consecutive patients with clinical suspicion for ARVC who were referred for CMR between 2015 and 2017. The presence of fatty infiltration and fibrosis were assessed using T2 imaging and myocardial delayed enhancement sequences, respectively. RV wall motions, volumes and ejection fraction (EF) of all patients were re-analysed and quantified. Available data on family history, Holter findings, and electrocardiograms were also reviewed.
RESULTS: There were 5 patients (7.7%) that fulfilled major CMR criteria for ARVC: 4 were classified as having definitive ARVC; and 1/5 as borderline. There were 33 patients with no RV dyskinetic segments: none were classified as having definitive or borderline ARVC; 4/33 were classified as possible ARVC, leaving 29/33 as normal or no ARVC. Finally, there were 27 remaining patients (41.5%) with isolated RV dyskinetic segments: 1/27 was classified as definitive ARVC; 4/27 as borderline; 8/27 as possible; leaving 15/27 as indeterminate. Compared to control, those with isolated RV dyskinesia (including the subgroup labelled as indeterminate 15/27) had more abnormal RVEF, larger RV end-diastolic volume index (82 ± 12 mL/m2 vs. 72 ± 12 mL/m2, p-value 0.0127), and a trend for higher odds of dilated RV (odds ratio 3.0 [0.81–11], p-value 0.09).
CONCLUSIONS: Among patients with a clinical suspicion for ARVC, almost 40% had isolated focal RV dyskinetic segments with the majority remaining unclassified. This cohort had more RV dilation and abnormal EF compared to control.
... In a study from a tertiary care center, misdiagnosis of ARVC was common with only 27% of 89 patients seeking a second opinion after receiving an ARVC diagnosis actually meeting TFC on secondary review. 22 Moreover, RV free wall contraction can result in areas of subjective bulging near the moderator band insertion, even in normal patients, which can mimic a wall motion Two representative cases of endocardial and epicardial voltage maps with corresponding regional strain analysis. A and C, A 25-year-old female patient, mutation negative genotype, presenting with resuscitated sudden cardiac death with a right ventricular (RV) ejection fraction of 36% and RV end-diastolic volume index of 115.2 mL/m 2 . ...
Background:
Arrhythmogenic right ventricular cardiomyopathy is an inherited cardiomyopathy characterized by fibrofatty replacement of right ventricular myocardium resulting in reentrant ventricular tachycardia (VT). Cardiac magnetic resonance imaging (CMR) can noninvasively measure regional abnormalities using tissue-tracking strain as well as late gadolinium enhancement (LGE). In this study, we examine arrhythmogenic substrate using regional CMR strain, LGE, and electroanatomic mapping (EAM) in arrhythmogenic right ventricular cardiomyopathy patients presenting for VT ablation.
Methods and results:
Twenty-one patients underwent right ventricular endocardial EAM, whereas 17 underwent epicardial EAM, to detect dense scar (<0.5 mV) as well as CMR study within 12 months. Quantitative regional strain analysis was performed in all 21 patients, although the presence of LGE was visually examined in 17 patients. Strain was lower in segments with dense scar on endocardial and epicardial EAM (-9.7±4.1 versus -7.3±4.0, and -9.8±2.8 versus -7.6±3.8; P<0.05), in segments with LGE scar (-9.9±4.4 versus -6.0±3.6; P=0.001), and at VT culprit sites (-7.4±3.7 versus -10.1±4.1; P<0.001), compared with the rest of right ventricular. On patient-clustered analysis, a unit increase in strain was associated with 21% and 18% decreased odds of scar on endocardial and epicardial EAM, respectively, 17% decreased odds of colocalizing VT culprit site, and 43% decreased odds of scar on LGE-CMR ( P<0.05 for all). LGE and EAM demonstrated poor agreement with κ=0.18 (endocardial, n=17) and κ=0.06 (epicardial, n=13). Only 8 (15%) VT termination sites exhibited LGE.
Conclusions:
Regional myocardial strain on cine CMR improves detection of arrhythmogenic VT substrate compared with LGE. This may enhance diagnostic accuracy of CMR in arrhythmogenic right ventricular cardiomyopathy without the need for invasive procedures and facilitate the planning of VT ablation procedures.
... 9 Among 89 patients diagnosed by general cardiologists after magnetic resonance (MR) imaging to have arrhythmogenic right ventricular cardiomyopathy, 73% did not meet the criteria for the disease when they were reinvestigated in a specialist centre. 10 In a multicentre study of non-invasive coronary angiography using computed tomography (CT), significant luminal narrowing was diagnosed erroneously in 5% of segments when compared with quantitative coronary arteriography (QCA). 11 Cardiovascular diseases such as myocardial infarction, pulmonary embolism, and acute aortic syndromes had been misdiagnosed in 18.7% of 970 autopsies. ...
Our use of modern cardiovascular imaging tools has not kept pace with their technological development. Diagnostic errors are common but seldom investigated systematically. Rather than more impressive pictures, our main goal should be more precise tests of function which we select because their appropriate use has therapeutic implications which in turn have a beneficial impact on morbidity or mortality. We should practise analytical thinking, use checklists to avoid diagnostic pitfalls, and apply strategies that will reduce biases and avoid overdiagnosis. We should develop normative databases, so that we can apply diagnostic algorithms that take account of variations with age and risk factors and that allow us to calculate pre-test probability and report the post-test probability of disease. We should report the imprecision of a test, or its confidence limits, so that reference change values can be considered in daily clinical practice. We should develop decision support tools to improve the quality and interpretation of diagnostic imaging, so that we choose the single best test irrespective of modality. New imaging tools should be evaluated rigorously, so that their diagnostic performance is established before they are widely disseminated; this should be a shared responsibility of manufacturers with clinicians, leading to cost-effective implementation. Trials should evaluate diagnostic strategies against independent reference criteria. We should exploit advances in machine learning to analyse digital data sets and identify those features that best predict prognosis or responses to treatment. Addressing these human factors will reap benefit for patients, while technological advances continue unpredictably.
... Fatty infiltration was formerly often sought as part of the imaging diagnosis of this disorder, but recent studies have indicated that many normal individuals will have a small amount of epicardial fat present along the right ventricular surface, and over-diagnosis of ARVD can occur based on this imaging criterion alone. 3 Abnormal right ventricular delayed-enhancement may prove to be a more robust diagnostic criterion, as it is infrequently seen with other disorders. In a small series reported previously, approximately two-thirds of patients with this disorder demonstrated abnormalities of delayed-enhancement imaging with abnormal right ventricular enhancement apparent. ...
The left ventricular size and function are normal. However, the right ventricle is mildly enlarged, and demonstrates areas of focal dyskinesia, with microaneurysm formation noted on the short-axis views involving the right ventricular anterior wall. Abnormal heavy trabeculation is seen involving the apical portion of the right ventricle as well. The right ventricular systolic function is depressed.
... 22,28 However, it also produces false positives, particularly if the criteria used are based solely on fibrofatty alterations and ventricular wall thickness. 18,24,29 In addition to false positives, other limitations of MRI are interobserver variability in interpretation of its findings, artefacts caused by arrhythmias, restrictions to its use in the presence of intracardiac devices, cost, and lack of availability in less specialized centers. 30 ...
A 67-year-old man was admitted to our hospital after episodes of syncope preceded by malaise and diffuse neck and chest discomfort. No family history of cardiac disease was reported. Laboratory workup was within normal limits, including D-dimers, serum troponin I and arterial blood gases. The electrocardiogram showed sinus rhythm with T-wave inversion in leads V1 to V3. Computed tomography angiography to investigate pulmonary embolism showed no abnormal findings. Transthoracic echocardiography (TTE) displayed massive enlargement of the right ventricle with intact interatrial septum and no pulmonary hypertension. Cardiac magnetic resonance imaging (MRI) confirmed right ventricular (RV) dilatation and revealed marked hypokinesia/akinesia of the lateral wall. Exercise stress testing was negative for ischemia.
According to the 2010 Task Force criteria for arrhythmogenic right ventricular dysplasia (ARVD), this patient presented two major criteria (global or regional dysfunction and structural alterations: by MRI, regional RV akinesia or dyskinesia or dyssynchronous RV contraction and RV ejection fraction ≤40%, and repolarization abnormalities: inverted T waves in right precordial leads [V1, V2, and V3]); and one minor criterion (>500 ventricular extrasystoles per 24 hours by Holter), and so a diagnosis of ARVD was made.
After electrophysiologic study (EPS) the patient received an implantable cardioverter-defibrillator (ICD).
This late clinical presentation of ARVD highlights the importance of TTE screening, possibly complemented by MRI. The associated risk of sudden death was assessed by EPS leading to the implantation of an ICD. Genetic association studies should be offered to the offspring of all ARVD patients.
... 22,28 However, it also produces false positives, particularly if the criteria used are based solely on fibrofatty alterations and ventricular wall thickness. 18,24,29 In addition to false positives, other limitations of MRI are interobserver variability in interpretation of its findings, artefacts caused by arrhythmias, restrictions to its use in the presence of intracardiac devices, cost, and lack of availability in less specialized centers. 30 ...
Abstract
Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D)
is an under diagnosed idiopathic progressive cardiomyopathy, associated
with mutations in genes coding for desmosomal proteins, with well-studied
hereditary mechanisms in some populations. The Task Force 2010 defined
diagnostic criteria for ARVC/D: structural (by echocardiography and cardiac
magnetic resonance imaging); histopathological (if biopsy is required); electrical
(by electrocardiography, exercise testing and Holter monitoring) and genetic/
familial. When those criteria are met, the associated sudden death risk should
be then tackled by EPS, leading to the eventual insertion of an Implantable
Cardioverter Defibrillator. Genetic association studies should be offered to
ARVC/D patient’s offspring.
... Alguns estudos mostraram que, na DAVD, a RMC tem um valor diagnóstico superior à ecocardiografia convencional 22,28 . No entanto, também está sujeita a falsos positivos, principalmente se forem utilizados critérios estritamente com base nas alterações fibroadiposas e da espessura da parede ventricular 18,24,29 . ...
A 67-year-old man was admitted to our hospital after episodes of syncope preceded by malaise and diffuse neck and chest discomfort. No family history of cardiac disease was reported. Laboratory workup was within normal limits, including D-dimers, serum troponin I and arterial blood gases. The electrocardiogram showed sinus rhythm with T-wave inversion in leads V1 to V3. Computed tomography angiography to investigate pulmonary embolism showed no abnormal findings. Transthoracic echocardiography (TTE) displayed massive enlargement of the right ventricle with intact interatrial septum and no pulmonary hypertension. Cardiac magnetic resonance imaging (MRI) confirmed right ventricular (RV) dilatation and revealed marked hypokinesia/akinesia of the lateral wall. Exercise stress testing was negative for ischemia. According to the 2010 Task Force criteria for arrhythmogenic right ventricular dysplasia (ARVD), this patient presented two major criteria (global or regional dysfunction and structural alterations: by MRI, regional RV akinesia or dyskinesia or dyssynchronous RV contraction and RV ejection fraction ≤40%, and repolarization abnormalities: inverted T waves in right precordial leads [V1, V2, and V3]); and one minor criterion (>500 ventricular extrasystoles per 24 hours by Holter), and so a diagnosis of ARVD was made. After electrophysiologic study (EPS) the patient received an implantable cardioverter-defibrillator (ICD). This late clinical presentation of ARVD highlights the importance of TTE screening, possibly complemented by MRI. The associated risk of sudden death was assessed by EPS leading to the implantation of an ICD. Genetic association studies should be offered to the offspring of all ARVD patients.
Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.
... On initial evaluation, all patients should have a physical exam and comprehensive clinical history that includes information about family history of sudden death and arrhythmias and an ECG, 24-h Holter monitoring, signal-averaged ECG, and comprehensive imaging of both ventricles should also be obtained. Although MRI is a very important diagnostic tool, it can also be a common cause for misdiagnosis ( Fig. 1) [13]. If the initial workup is suggestive but not diagnostic of ARVD/C, an electrophysiology study should be considered to establish the diagnosis. ...
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited cardiomyopathy characterized by ventricular arrhythmias, right ventricular dysfunction, and sudden cardiac death. Since the first description of ARVD/C in 1982, there have been major advances in the diagnosis and management of the disease. For instance, the discovery of desmosomal abnormalities as a genetic basis for ARVD/C; the importance of proband status and ventricular ectopy for risk stratification of patients at risk for sudden cardiac death; and the critical role that exercise plays in the development and progression of ARVD/C, just to name a few. From a treatment perspective, the placement of implantable cardioverter defibrillators in those at risk for sudden cardiac death and ablation techniques have also evolved over time. In 2010, an update of the 1994 Task Force Diagnostic criteria for ARVD/C was published with the hope to increase diagnostic sensitivity. This update incorporates new knowledge and technology to assess structural cardiac abnormalities and is the standard for diagnosis today.
... These findings should be taken into account since RV dyskinesia or aneurysm are major diagnostic criterion for ARVC, which can be mimicked by either common diseases or even normal variants in healthy individuals [67]. The clinical consequences of misinterpretation of the RV WMA by CMR have been documented [69]. Furthermore, it has been shown that identification of WMA only on the basis of visual echocardiographic assessment may be inaccurate [37]. ...
Right ventricular (RV) size and function have been found to be important predictors of cardiovascular morbidity and mortality in patients with various conditions. However, non-invasive assessment of the RV is a challenging task due to its complex anatomy and location in the chest. Although cardiac magnetic resonance (CMR) is considered a "gold standard" for RV assessment, the development of novel echocardiographic techniques, including three-dimensional (3DE) and two-dimensional speckle-tracking echocardiography (2DSTE) opened new exciting opportunities in RV imaging. 3DE has proven accurate in measuring RV volumes and ejection fraction when compared with CMR while 2DSTE plays a critical role in measuring RV myocardial deformation, which is a powerful predictor of patients' functional capacity and survival. Cardiac computed tomography provides an accurate and reproducible assessment of the RV volumes and can be considered a reliable alternative for patients who are not suitable for either echocardiography or CMR. The purpose of this review is to summarize currently available data on the role of the different noninvasive cardiac imaging modalities in assessment of RV size, function and mechanics, with an emphasis on the benefits of novel imaging techniques and on how the latter can be applied in the various clinical settings.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited genetic cardiomyopathy caused by mutations in the gene encoding proteins of desmosome complexes. To illustrate some challenges with ARVC diagnosis, we present the case of a young patient with family history of sudden cardiac death whose baseline cardiac MRI (CMR) results were normal. Upon development of additional arrhythmic abnormalities 3 years later, CMR was repeated and revealed abnormalities suggestive of ARVC. Since certain diagnoses, including ARVC, may have serious consequences if the timely diagnosis is not made, clinical and imaging clues need to be integrated taking the pre-test likelihood of the disease in question into consideration.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by fibrofatty infiltration of predominantly the right ventricular (RV) myocardium. Affected patients typically present as young adults with hemodynamically stable ventricular tachycardia, although pediatric cases are increasingly recognized. These young subjects often have a more severe phenotype with a high risk of sudden cardiac death (SCD) and progression toward heart failure. Diagnosis of ARVC is made by combining multiple sources of information as prescribed by the consensus-based Task Force Criteria. The description of Naxos disease, a fully penetrant autosomal recessive disorder that is associated with ARVC and a cutaneous phenotype of palmoplantar keratoderma and wooly hair facilitated the identification of the genetic cause of ARVC. At present, approximately 60% of patients are found to carry a pathogenic variant in one of five genes associated with the cardiac desmosome. The incomplete penetrance and variable expressivity of these variants however implies an important role for environmental factors, of which participation in endurance exercise is a strong risk factor. Since there currently is no definite cure for ARVC, disease management is directed toward symptom reduction, delay of disease progression, and prevention of SCD. This clinically focused review describes the spectrum of ARVC among children and adolescents, the genetic architecture underlying this disease, the cardio-cutaneous syndromes that led to its identification, and current diagnostic and therapeutic strategies in pediatric ARVC subjects.
Three‐dimensional (3D) reconstruction by means of electroanatomic mapping (EAM) systems, allows for the understanding of the mechanism of focal or re‐entrant arrhythmic circuits, which can be identified by means of dynamic (activation and propagation) and static (voltage) color‐coded maps. However, besides this conventional use, EAM may offer helpful anatomical and functional information for tissue characterisation in several clinical settings. Today, data regarding electromechanical myocardial viability, scar detection in ischaemic and nonischaemic cardiomyopathy and arrhythmogenic right ventricle dysplasia (ARVC/D) definition are mostly consolidated, while emerging results are becoming available in contexts such as Brugada syndrome and cardiac resynchronisation therapy (CRT) implant procedures. As part of an invasive procedure, EAM has not yet been widely adopted as a stand‐alone tool in the diagnostic path. We aim to review the data in the current literature regarding the use of 3D EAM systems beyond the definition of arrhythmia. This article is protected by copyright. All rights reserved
Cardiac magnetic resonance (CMR) imaging has gained significant traction as an imaging modality of choice in the evaluation of individuals with, or at risk for, heart failure. Ventricular arrhythmias, often malignant, may be sequelae of heart failure and arise from fibrosis. Late gadolinium enhancement evaluation by CMR has become a preferred modality to assess individuals at risk for malignant ventricular arrhythmias. A spectrum of various pathologies that predispose individuals to malignant ventricular arrhythmias, as well as the usefulness of CMR in their identification and prognostication, are reviewed.
Introduction:
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited progressive cardiomyopathy characterized by frequent life-threatening arrhythmias. The diagnosis of ARVC is challenging and is based on a set of major and minor criteria as described by the modified Task Force Criteria (TFC). We report our clinical experience in a series of patients who were misdiagnosed with ARVC and subsequently underwent removal of their implantable cardioverter defibrillator (ICD) after a re-evaluation at our center.
Methods and results:
We studied 12 patients who were misdiagnosed with ARVC and had ICD implantation prior to our assessment. All patients had a repeat evaluation and were scored according to TFC prior to ICD removal. Cardiac magnetic resonance imaging (CMR) studies performed at outside institutions during the initial evaluation were reported abnormal and classified as meeting major TFC in ninety percent of patients. The most common abnormality reported was fatty infiltration of the right ventricular (RV) free wall and/or presence of focal intra-myocardial fat in 6 patients (50%). On re-evaluation, none of these findings fulfilled the TFC for the diagnosis.
Conclusion:
This study demonstrated that high dependence on misinterpretation of CMR along with a misunderstanding of the TFC evaluation are the main reasons for the misdiagnosis of ARVC. Despite the updated criteria for almost a decade, this study reminds that the diagnosis of ARVC is complex and hence careful TFC evaluation and consideration of multiple cardiac test results should be the focused approach for clinicians when confronted with suspected ARVC patients. This article is protected by copyright. All rights reserved.
This chapter reviews the relationship between late gadolinium enhancement (LGE) and risk of ventricular arrhythmias in other non‐ischemic cardiomyopathies. The risk of ventricular arrhythmias associated with LGE on cardiac magnetic resonance (CMR) has also been validated in patients with the apical variant of hypertrophic cardiomyopathy (HCM), where those with a higher number of myocardial segments with LGE were at increased risk of ventricular arrhythmias. Although echocardiography is frequently the first modality used to identify and diagnose left ventricular non‐compaction (LVNC), CMR offers multiple benefits that may improve both diagnosis and identification of high‐risk patients. LVNC is a congenital cardiomyopathy with characteristic prominent ventricular trabeculae thought to be secondary to an arrest in endomyocardial development. Arrhythmogenic right ventricular dysplasia is a predominantly genetic cardiomyopathy characteristically affecting portions of the right ventricle with fibro‐fatty replacement of normal myocardium.
Ventrikuläre Extrasystolen (VES) sind ein häufiger, oft zufälliger und meist harmloser Befund. Bei sehr häufigem Auftreten mit Beschwerden oder Verschlechterung der linksventrikulären Funktion besteht eine Behandlungsindikation. Idiopathische ventrikuläre Tachykardien (VT) finden sich überwiegend bei Patienten mit strukturell gesundem Herz. Diese VES/VT haben meist einen fokalen Ursprung. Der wahrscheinlichste Mechanismus sind verzögerte Nachdepolarisationen. Die Lokalisation des Ursprungortes basiert auf der Erstellung eines Aktivierungsmaps mit oder ohne Kombination eines Pacemappings. Die charakteristischen anatomischen Ursprungsstellen idiopathischer VES/VT sind die Ausflussbahnen des rechten und linken Ventrikels einschließlich der Aortenwurzel. Weitere typische Lokalisationen sind der Trikuspidal- oder Mitralklappenring, Papillarmuskeln und Purkinje-Fasern. Die Katheterablation ist bei symptomatischen, monomorphen VES/VT eine Alternative zu antiarrhythmischer Medikation. Die Erfolgsrate ist hoch, wobei das Mapping und die Ablation oftmals eine Herausforderung darstellen können. Dieser Artikel ist der fünfte Teil einer Serie zur gezielten Fort- und Weiterbildung im Bereich „Spezielle Rhythmologie – Invasive Elektrophysiologie“. Er beschreibt pathophysiologische Grundlagen, Formen sowie typische Befunde, die bei einer elektrophysiologischen Untersuchung erhoben werden können.
Aim:
To assess the role of cardiovascular magnetic resonance imaging (CMRI) in patients referred for suspected arrhythmogenic right ventricular cardiomyopathy (ARVC), its ability to identify ARVC mimics, and subsequent clinical impact.
Materials and methods:
The CMRI registry of the year 2014 was analysed to identify all consecutive patients referred for suspected ARVC. A comprehensive CMRI protocol that included anatomy, bi-ventricular function modules, and late gadolinium enhancement (LGE) was performed in all patients.
Results:
Out of 2,481 CMRI performed, 124 patients (5%) were referred for suspected ARVC. A pathological substrate was identified at CMRI in 36 patients (29%): five patients (4%) had ischaemic heart disease (IHD) and 10 (8%) non-IHD; five patients (4%) met CMRI criteria for ARVC and 16 (13%) were ARVC mimics. right ventricular end-diastolic volume (RVEDV) and right ventricular stroke volume (RVSV) were significantly higher in patients with ARVC mimics (RVEDV p=0.007, RVSV p=0.012) and ARVC (RVEDV p=0.013, RVSV p=0.013), as compared to those with structurally normal hearts. CMRI was superior to echocardiography in the identification of ARVC mimics (13% versus 1%, p=0.01).
Conclusions:
CMRI was able to identify 16 (13%) ARVC mimics, from congenital abnormalities to acquired heart disease. CMRI was superior in identifying ARVC mimics compared to echocardiography, and overall provided a change in diagnosis in 22% of patients.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a recognised cause of sudden cardiac death during exercise in young athletes. Competitive exercise is also known to accelerate progression of ARVC and exercise restriction is an important part of disease management. Regular endurance training can induce physiological changes detectable on electrocardiography and imaging which may overlap with pathological findings caused by ARVC, thus making differentiation of athlete's heart from ARVC difficult in some cases. This review will discuss the changes of athlete's heart, particularly as it affects the right ventricle, the diagnostic criteria for ARVC and how diagnostic accuracy is affected in athletes. A practical approach to this clinical problem is outlined.
L'imagerie par résonance magnétique (IRM) est un outil remarquable pour le diagnostic clinique, aussi bien pour l'imagerie cérébrale que pour l'imagerie cardiaque et abdominale. En IRM cardiaque, deux problèmes sont récurrents : la non reproductibilité des cycles cardiaques et le mouvement respiratoire. L'IRM cardiaque morphologique est généralement faite avec une séquence composée d'une préparation longue, visant à annuler le signal du sang pour accentuer le contraste au niveau du myocarde, et de l?acquisition à proprement parler. Ces acquisitions sont généralement faites en mésodiastole (phase de relaxation passive du coeur) ce qui permet de satisfaire les contraintes liées à l'annulation du sang et d'éviter les problèmes liés aux non reproductibilités des cycles cardiaques car la mésodiastole est longue. Il est donc difficile de satisfaire les contraintes liées à l?annulation du sang pour faire les acquisitions en télésystole (phase où le coeur est contracté) à cause des non reproductibilités cardiaques car la télésystole est courte. Afin de passer outre ces limitations et de pouvoir acquérir ces mêmes images morphologiques en télésystole, nous proposons une nouvelle méthode adaptative qui permet à la fois de placer la fenêtre d'acquisition de manière optimale et de satisfaire les contraintes liées à l'annulation du sang. Une application de cette méthode a également été mise en place pour estimer et comparer les temps de relaxation transversale (T2) entre télésystole et mésodiastole. Pour la gestion prospective du mouvement respiratoire, le point crucial est d'estimer les mouvements en temps réel en perturbant au minimum les signaux de résonance magnétique. Pour ce faire nous proposons une méthode basée sur l'estimation paramétrique des mouvements en temps réel à partir des signaux physiologiques disponibles (ceintures respiratoires et ECG). Cette méthode a été testée et les résultats montrent son intérêt et sa fiabilité par rapport aux erreurs faites au niveau du mouvement. Une méthode de reconstruction incluant les mouvements a également été utilisée pendant ces travaux afin de faire de l'imagerie en télésystole en respiration libre et d'utiliser d'autres types de capteurs respiratoires comme certains signaux de résonance magnétique. Ainsi pendant ces travaux, des méthodes adaptatives ont été mises en place afin de mieux gérer le mouvement et de prendre en compte les spécificités de chaque patient. Ces travaux ouvrent la voie de l'imagerie par résonance magnétique adaptative pleinement fonctionnelle dans un contexte clinique
Regelmäßige körperliche Aktivität hat zahlreiche positive Auswirkungen in der Prävention und Therapie von kardiovaskulären und anderen Erkrankungen. Körperliche Aktivität kann wie ein Medikament mit Wirkung und Nebenwirkungen eingesetzt werden. Kardiale Komplikationen im Sport sind selten, treten sie aber auf, stellen sie ein dramatisches Ereignis dar. Besonders problematisch sind plötzliche Zwischenfälle und der plötzliche Tod im Kindesalter. In diesem Kapitel werden die genetisch bedingten elektrischen und strukturellen Ursachen kardialer Zwischenfälle dargestellt, insbesondere die Ionenkanalerkrankungen und verschiedenen Formen genetisch bedingter Kardiomyopathien sowie die auslösenden Trigger. Ergänzend werden das WPW-Syndrom und das Vorhofflimmern bei Sportlern erläutert; bei beiden Arrhythmien spielen genetische Faktoren teilweise ebenfalls eine Rolle. Die Diagnostik allgemein und die genetische Abklärung werden dargestellt, ebenso die Risikoabschätzung und die Konsequenzen für die sportärztliche Vorsorgeuntersuchung. Ergänzend werden die aktuellen Empfehlungen zur genetischen Untersuchung aufgeführt.
Myocardial infarction, scarring, and viability are simultaneously examined using the technique of delayed-enhancement MR. Multiple experimental studies have demonstrated an excellent spatial correlation between the extent of hyper-enhancement on delayed-enhancement imaging, and areas of myocardial necrosis (acute MI) or scarring (chronic MI) at histopathology (Figure 3.1).1 In patients, delayed-enhancement MR has been shown to be highly effective in identifying the presence, location, and extent of myocardial infarction in both the acute and chronic settings.2, 3 Additionally, it has been shown to be superior to SPECT for the detection of subendocardial myocardial infarction (Figure 3.2).4
The left ventricle is minimally elongated in the vertical axis. The septum is noted to be dyskinetic from the basilar level to the apex. The anterior, anterolateral, inferolateral and inferior walls of the left ventricle demonstrate minimally reduced wall motion.
Delayed enhancement imaging demonstrates transmural enhancement of the antero-septum at the basal and midventricular levels, with preservation of the apical septum. In addition, extensive enhancement of the right ventricular free wall is noted. A small focus of possible enhancement is noted in the lateral wall of the left ventricle as seen in the fourth image of the third row.
The left ventricular wall thickness and cavity size appear normal. The right ventricle is enlarged, and demonstrates a global decrease in systolic function. In addition, focal areas of dyskinesia are noted along the free wall in the short-axis views, particularly near the outflow tract. Abnormal trabeculation is apparent throughout the right ventricle, and is particular notable at the apex.
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a genetically determined myocardial disease predominantly affecting the right ventricle (RV). There is no single gold standard for the diagnosis of ARVC/D. New echocardiographic tools such as tissue deformation imaging allow quantitative regional wall motion analyses. This is especially important for early ARVC/D diagnosis where global RV dysfunction may be lacking. Several studies have shown incremental diagnostic value for tissue deformation imaging derived parameters in comparison to conventional echocardiography. 3D RV echocardiography is a new method to evaluate the RV and provides volumetric measurements in a broad spectrum of ARVC/D patients. Due to the frequent implantation of implantable cardioverter devices, echocardiography could play an important role in the follow-up of ARVC/D patients. Emerging new echocardiographic tools are currently changing the role of echocardiography in ARVC/D. In the future, MRI and echocardiography should be considered complementary to evaluate ARVC/D.
In patients with heart failure, right ventricular (RV) function is an independent predictor of cardiovascular morbidity and mortality. However, non-invasive assessment of the RV is a challenging task due to its complex anatomy and location in the chest.Moreover, the high load dependency of RV function can also lead to inaccurate or misleading interpretation of intrinsic RV function parameters if they are taken in isolation form RV pre- and afterload conditions. No single imaging modality is able to provide a comprehensive assessment of RV global and regional functions, mechanics, shape and tissue structure. Accordingly, a multimodality and multiparameteric approach is recommended.
The following chapter summarizes currently available data on the role of non-invasive imaging techniques in the assessment of RV performance, their advantages, limitations and pitfalls in heart failure patients, with an emphasis on the relative merits of newer imaging parameters and practical approach to data acquisition and analysis.
Current Task Force criteria (TFC) of Cardiac Magnetic Resonance (CMR) for the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC/D) were generated by comparing probands (mean age of 44 years) to healthy participants of the MESA study (mean age of 60 years). These age differences may be a selection bias because right ventricular (RV) end-diastolic volume index (EDVi) decreases 4.6% per decade. Moreover, fat infiltration and late gadolinium enhancement (LGE) were not included. We evaluated the diagnostic accuracy of TFC using the same methodology used by the Task force but comparing probands and age- and sex-matched healthy controls and considering also other morpho-functional and tissue abnormalities detected by CMR. Forty-seven probands with previous diagnosis of ARVC/D (excluding probands if CMR was used for diagnosis) were compared with 216 age- and sex-matched healthy controls. TFC had optimal specificity (100%) but poor sensitivity (20% for major, 13% for minor criteria). The presence of any pre- and post-contrast signal abnormalities had 100% specificity and 81% sensitivity. The best diagnostic accuracy (98%) was achieved by the combined evaluation of any RV wall motion abnormality (excluding hypokinesia) with any signal abnormality (including LV fat infiltration and LGE) yielding a 100% specificity and 96% sensitivity. LV was involved in 45% of the probands. Current TFC for CMR presented optimal specificity but poor sensitivity to identify patient with ARVC/D. Signal and wall motion parameters of CMR should be considered together to achieve the best diagnostic accuracy for the diagnosis of ARVC/D.
Introduction-Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C) is an inherited cardiomyopathy characterized by ventricular arrhythmias, an increased risk of sudden death, and abnormalities of right (and less commonly left) ventricular structure and function. Although structural involvement of the right ventricle predominates, a left dominant form is seen. In most patients in the United States, structural abnormalities of the right ventricle predominate. The pathologic hallmark of ARVD/C is myocyte loss with fibrofatty replacement. Since the first detailed clinical description of the disorder in 1982, significant advances have been made in our understanding of all aspects of this disease. Mutations predominantly in desmosomal proteins have been determined to be the genetic basis of ARVD/C in up to two-thirds of affected individuals. There is increasing evidence supporting a relationship between exercise and ARVD/C. It has been observed that exercise causes an earlier onset and more severe arrhythmic and structural disease, suggesting that this is a very important environmental factor for the development and progression of ARVD/C. It has been proposed that exercise and genetic predisposition have an additive effect towards a threshold for ARVD/C pathogenesis. However, there are very few recommendations as to what is the appropriate level of exercise that will not cause triggering of the onset of the disease. The purpose of this chapter is to review of the natural history, clinical presentation, diagnosis, and treatment of patients with ARVD/C with specific attention to the role of exercise in the pathogenesis of ARVD/C.
There is a major trade-off between improvements in longevity, general health, fitness and quality of life due to regular intense physical activity on the one hand and possible cardiac risks on the other hand, whether for participants in leisure time sports activities or for highly trained athletes. Cardiac complications and sudden death in sports, even though rare, but dramatic, events, are mainly observed in those suffering from inherited, often latent diseases with a strong genetic background, unknown to the subjects. Sedentary lifestyle together with more than one risk factor may also contribute to cardiac events in persons beginning to exercise for the first time or recommencing intense physical activities after a long pause.
Manifestations of inherited cardiac diseases with a typical genetic component may occur in children or adolescents, but also in adults. For many inherited cardiac diseases there is a large body of knowledge on the genetic origin, therefore, genetic testing may be a valuable tool for diagnosis and prevention of underlying diseases, especially as genetic testing has become much cheaper over the last few years.
The present paper describes cardiac diseases with genetic disposition and related genetic testing and presents recommendations for genetic examinations. Testing should be of benefit for sportsmen and women but also for family members to prevent fatal cardiac events. These recommendations will consider benefits for the sports person, and ethical reflections as well.
Purpose of review:
The purpose is to describe the recent advances made in imaging of the right heart, including deformation imaging, tissue, and flow characterization by MRI, and molecular imaging.
Recent findings:
Recent developments have been made in the field of deformation imaging of the right heart, which may improve risk stratification of patients with heart failure and pulmonary hypertension. In addition, more attention has been given to load adaptability metrics of the right heart; these simplified indices, however, still face challenges from a conceptual point of view. The emergence of novel MRI sequences, such as native T1 mapping, allows better detection and quantification of myocardial fibrosis and could allow better prediction of postsurgical recovery of the right heart. Other advances in MRI include four-dimensional flow imaging, which may be particularly useful in congenital heart disease or for the detection of early stages of pulmonary vascular disease.
Summary:
The review will place the recent developments in right heart imaging in the context of clinical care and research.
CMR can evaluate myocardial contractility, volumetry, strain, flow, perfusion, viability, and vascular anatomy without ionizing radiation or iodinated contrast agents. Multiple pulse sequences are acquired in different orientations to the heart and relevant vasculature, some of which require gadolinium-based contrast agents. A strength of CMR is the ability to determine tissue characteristics including edema, hemorrhage, iron content, inflammation, and diffuse and focal fibrosis useful for the diagnosis of cardiomyopathic processes, pericardial disease, and cardiac masses. CMR assessment of cardiovascular structure, function, hemodynamics, extracardiac vasculature and thoracic structure, makes it a useful adjunct to echocardiography in patients with congenital heart disease and valvular disease. Although imaging of the coronary arteries is feasible with CMR, CCTA is the gold standard for noninvasive coronary angiography providing detailed visualization of the entire coronary artery tree. Decisions related to performing CMR versus CCTA require information patient profile and strengths and limitations of each modality in relation to the posed clinical question.
Cardiovascular magnetic resonance imaging provides a multifaceted and comprehensive assessment for the diagnosis and treatment of cardiovascular disease, including cardiovascular structures, function, tissue characterization, myocardial perfusion, and metabolism. Applications include the assessment of coronary artery disease, pathologic myocardial substrates, congenital heart disease, thoracic vasculature, valvular function, masses, and electrophysiologically relevant substrates. Advances in technology will continue to lead to novel clinical and research applications.
268 preselected subjects were extensively studied and the diagnosis of right ventricular dysplasia (RVD) was made in 108 living and 18 deceased patients, 35% of cases being familial. Subsequently we studied 72 subjects from nine families in which a case of sudden death had occurred with the autoptic diagnosis of RVD. In 42 out of 72 cases the autoptic (11 patients), clinical-echocardiographic (30 patients) and haemodynamic (15 patients) data supported the diagnosis of RVD. In all but one deceased patient, death was sudden, while in all the living family members we observed ventricular arrhythmias, mostly with left bundle branch block morphology. Both manifest and concealed forms were documented with polymorphic presentation and with clinical-pathologic findings similar to the non-familial RVD cases. This study confirms the presence of a familial form of RVD that is probably more frequent than previously thought. Preliminary data seem to indicate an autosomal dominant inheritance with incomplete penetrance and variable expression.
Arrhythmogenic right ventricular disease (ARVD) is increasingly found in young adults with ventricular arrhythmias and is characterized by ventricular tachycardia originating within the right ventricle and regional or diffuse abnormalities in the contraction of the right ventricle. Until now, the gold standard for the detection of global and regional abnormalities of the right ventricular wall has been angiography combined with biopsy. The purpose of the current study was to compare MR imaging with angiography for assessing the location and extent of morphologic and functional abnormalities in patients with ARVD.
Electrocardiographically gated spin-echo and cine gradient-echo MR imaging of the heart was performed in 36 consecutive patients with biopsy-proved ARVD. Patients were prospectively separated into two groups according to the results of invasive electrophysiologic tests (18 with inducible ventricular tachycardia during invasive electrophysiologic studies [ARVD 1] and 18 without inducible ventricular tachycardia [ARVD 2]) and compared with 11 control subjects. Global and regional morphology and function of the right ventricle were assessed with MR imaging, and those findings were compared with angiographic findings.
Right ventricular ejection fraction was significantly lower in patients with ARVD 1 than in patients with ARVD 2 or in control subjects. Regional abnormalities of the right ventricular wall also were more pronounced in patients with ARVD 1 than in patients with ARVD 2. Signal-intensity increases corresponding to fatty replacement shown by biopsy were seen in 33% of patients with ARVD 1 and in 11% of patients with ARVD 2. Abnormal regions of the right ventricular wall seen on MR images corresponded to angiographic findings in 86% of patients. Comparison with control subjects showed that patients with ARVD 1 had a significant delay in diastolic relaxation of the right ventricle.
Our results show that MR imaging can be used to assess morphologic alteration, tissue abnormalities, and global as well as regional dysfunction of the right ventricle in patients with ARVD. It may become a useful clinical tool for diagnosing and grading ARVD and a worthy substitute for angiography and biopsy in the follow-up of patients with ARVD.
Autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVD, MIM 107970) is one of the major causes of juvenile sudden death. We have previously assigned the disease locus to chromosome 14q23-q24. Here we report on a novel variant of ARVD, which is transmitted associated to 1q42-q43 and is characterized by a concealed form, showing effort-induced polymorphic tachycardias. Since both loci ARVD1 and ARVD2 map in proximity of alpha-actinin genes, the possible implication of these myofibrillar proteins in the pathogenesis of ARVD is discussed. Two additional ARVD families, tested with markers of chromosomes 1q42-q43 and 14q23-q24, failed to show linkage, providing evidence of further genetic heterogeneity.
Arrhythmogenic right ventricular dysplasia (ARVD) is a heart disease characterized by a total or partial fat replacement of the myocardium. A total of 30 patients were studied with a suspected diagnosis of ARVD. Clinical criteria used for evaluation of ARVD were: (a) ventricular origin arrhythmias with a left bundle branch block configuration, (b) T-wave inversion in the anterior precordial leads, (c) ventricular kinetic alterations observed using echocardiography and angiography and (d) cardiac failure when there are no pathologies attributable to other heart diseases. All patients had serial EKG and echocardiography tests. One third of patients underwent angiocardiography; 7 of 30 had Holter; 7 of 30 had exercise test just to evaluate the effectiveness of the anti-arrhythmic therapy. All patients underwent MRI examination. The following MRI criteria were used: (a) high-intensity areas indicating the fatty substitution of the myocardium, (b) ectasia of the right ventricular outflow tract, (c) dyskinetic bulges, (d) dilation of the right ventricle and (e) enlargement of the right atrium. The diagnosis of ARVD was classified as highly probable for patients manifesting at least three positive criteria, probable with two positive criteria, dubious with one and negative in the absence of all criteria. Highly probable diagnosis of ARVD was made in 8 patients, probable in 4, dubious in 7 and negative in 11. The MRI technique is very effective in the assessment of ARVD. The MRI criteria may be helpful in the diagnosis of this condition.
Arrhythmogenic right ventricular dysplasia (ARVD) is a new form of cardiomyopathy probably more frequent than commonly reported. It is a rare but important cause of sudden arrhythmic death in young, otherwise healthy persons, as well as a subtle cause of congestive heart failure. It may lead to temporary incapacitation with catastrophic consequences. Proper electrocardiographic criteria, echocardiography, nuclear medicine, or magnetic resonance imaging could identify most of these individuals. With the exception of full-thickness histological examination of the right ventricular free wall, contrast ventriculography remains the most definitive standard for a positive diagnosis. The wide clinical spectrum of arrhythmogenic right ventricular cardiomyopathies/dysplasia appears to be the result of one or possibly two factors: (a) replacement of most of the right ventricular myocardium by fat and (b) genetic susceptibility to environmental agents (myocarditis). Current treatment modalities include drug therapy, catheter or surgical ablative techniques, and modern treatments of congestive heart failure. Heart transplant is exceptional. Implantable defibrillators, used alone or in combination with drug therapy, will probably play an increasing role in ARVD and related cardiomyopathies.
Objective—To assess the relation between exercise intensity and oxygen uptake during graded exercise in paediatric patients who underwent surgical repair of congenital heart disease, and to compare it with conventional measures of aerobic exercise function. Design—Cross sectional study. Exercise testing was performed on a treadmill and gas exchange was measured on a breath by breath basis. Patients—29 patients who underwent an atrial switch operation for transposition of the great arteries (TGA) (mean (SD) age at testing 10.3 (2.5) years) and 30 patients who underwent total repair of tetralogy of Fallot (TF) (age 12.1 (3.3) years) performed graded exercise testing. Exercise responses were compared with data obtained in 24 normal controls (age 11.4 (2.6) years). Results—The slope of oxygen uptake versus exercise intensity averaged 1.50 (0.64) ml O 2 /min 2 /kg in the patients with TGA and 1.68 (0.75) ml O 2 /min 2 /kg after TF repair, both lower (p < 0.005) than in normal controls (2.42 (0.68) ml O 2 /min 2 /kg). The lower slope of oxygen uptake was correlated with a subnormal value for ventilatory anaerobic threshold, which averaged 78.0 (13.3)% of normal in TGA and 85.
Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown etiology that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. We investigated the relationship between the electrocardiogram (ECG) appearances and signal-averaged ECG (SAECG) in 7 cases with ARVD, and evaluated the usefulness of SAECG as a screening test to detect patients with ARVD. Compared with the conventional 12-lead ECG, the SAECG detects abnormalities at a higher rate in ARVD patients (57% versus 86%). SAECG was more sensitive as a screening test to detect patients with ARVD than 12-lead ECG.
Arrhythmogenic right ventricular cardiomyopathy (ARVC), also known as arrhythmogenic right ventricular dysplasia, is a disorder of the heart muscle of unknown origin. It is characterized by electrical instability of the heart as a result of replacement of the right ventricular myocardium with fatty or fibrous fatty tissue. Dilatation of the right ventricle; fatty tissue in conspicuous trabeculae of the right ventricle, especially in the anterior wall, apex, and inferior (diaphragmatic) wall; and a scalloped appearance (bulging) of the right ventricular wall are characteristic findings at helical computed tomography (CT) that may be used to diagnose ARVC. Fatty tissue in the left ventricle and ventricular septum is seen relatively frequently in ARVC, and fat in the ventricular septum is another useful finding for diagnosis of ARVC with helical CT. ARVC is usually diagnosed on the basis of clinical or pathologic findings, and electron-beam CT is superior to nongated helical CT in assessment of abnormal right ventricular function. However, with knowledge of the characteristic findings, standard nongated helical CT can be helpful in diagnosing ARVC.
Background:
Magnetic resonance (MR) imaging is frequently used to diagnose arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). However, the reliability of various MR imaging features for diagnosing ARVC/D is unknown. The purpose of this study was to determine which morphologic MR imaging features have the greatest interobserver reliability for diagnosing ARVC/D.
Methods:
Forty-five sets of films of cardiac MR images were sent to 8 radiologists and 5 cardiologists with experience in this field. There were 7 cases of definite ARVC/D as defined by the Task Force criteria. Six cases were controls. The remaining 32 cases had MR imaging because of clinical suspicion of ARVC/D. Readers evaluated the images for the presence of (a) right ventricle (RV) enlargement, (b) RV abnormal morphology, (c) left ventricle enlargement, (d) presence of high T(1) signal (fat) in the myocardium, and (e) location of high T(1) signal (fat) on a Likert scale with formatted responses.
Results:
Readers indicated that the Task Force ARVC/D cases had significantly more (chi(2) = 119.93, d.f. = 10, p < 0.0001) RV chamber size enlargement (58%) than either the suspected ARVC/D (12%) or no ARVC/D (14%) cases. When readers reported the RV chamber size as enlarged they were significantly more likely to report the case as ARVC/D present (chi(2)(= )33.98, d.f. = 1, p < 0.0001). When readers reported the morphology as abnormal they were more likely to diagnose the case as ARVC/D present (chi(2) = 78.4, d.f. = 1, p < 0.0001), and the Task Force ARVC/D (47%) cases received significantly more abnormal reports than either suspected ARVC/D (20%) or non-ARVC/D (15%) cases. There was no significant difference between patient groups in the reported presence of high signal intensity (fat) in the RV (chi(2) = 0.9, d.f. = 2, p > 0.05).
Conclusions:
Reviewers found that the size and shape of abnormalities in the RV are key MR imaging discriminates of ARVD. Subsequent protocol development and multicenter trials need to address these parameters. Essential steps in improving accuracy and reducing variability include a standardized acquisition protocol and standardized analysis with dynamic cine review of regional RV function and quantification of RV and left ventricle volumes.
BACKGROUNDS. Magnetic Resonance (MR) imaging gives information about the complex anatomy of the right ventricle (RV). Because of the capability of tissue characterization, in addition to the functional and morphologic analysis, MR imaging is an optimal technique to investigate patients (pts) with clinical suspicion of arrhythmogenic right ventricular dysplasia (ARVD). METHODS. The purpose of the current study was to investigate a group of 55 pts with ventricular arrhythmias in order to detect ARVD. MR was performed with a 0.5 magnet (MR MAX PLUS G.E. Medical System). Electrocardiographically gated spin-echo and gradient-echo MR images of the heart were obtained in both transverse and sagittal planes. Sustained ventricular tachycardia (SVT) was present in 14 pts, non sustained ventricular tachycardia (NSVT) in 13 pts, left bundle block ventricular premature complexes > 10000/24 h (VPC/LBB) in 28 pts. The abnormalities analyzed were: presence of focal or diffuse fatty replacement of myocardium, segmental or global dilatation of the RV, reduction of ejection fraction with akinetic or dyskinetic areas, disarrangement of the trabecular pattern with the hypertrophy of the moderator band. RESULTS. When intramyocardial fatty replacement and at least two of the abnormalities were present we considered the MR aspects compatible with the diagnosis of ARVD. We detected the presence of ARVD in 8/14 pts with SVT, in 4/13 pts with NSVT, in 4/28 pts VPC/LBB. In 10/16 pts with ARVD left ventricular abnormalities (areas of fatty replacement of the myocardial wall and/or reduction of ejection fraction) were also present. The left ventricle involvement was detected in 5 pts with SVT, in 2 pts with NSVT, in 3 pts with VPC/LBB. Even if in 31 pts it was not possible to identify aspects compatible with the diagnosis of ARVD, some structural abnormalities of RV were also present. Because of its non-invasiveness MR is an excellent technique for the detection of ARVD, and of minor right ventricular abnormalities.
This 70 year old man had familial arrhythmogenic right ventricular cardiomyopathy (ARVC) with recurrent ventricular tachycardia since the age of 41. The diagnosis of ARVC was made on the basis of recurrent, refractory ventricular tachycardia, echocardiographic findings, a positive family history, and the detection on magnetic resonance imaging (MRI) of fatty …
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD) is a dominantly inherited disorder progressively affecting the myocardium and it is one of the major causes of juvenile sudden death. The chromosomal localization of the disease gene is reported here for the first time. A maximum lod score of 6.04 was obtained at theta = O for linkage with the polymorphic marker D14S42 (14q23-q24) in two families, one of which has 82 subjects (19 affected) in four generations. The pre-symptomatic identification of ARVD carriers by linkage analysis in the affected families strongly increases the possibility of prevention of life-threatening complications.
OBJECTIVES
We sought to define the clinical picture and natural history of familial arrhythmogenic right ventricular cardiomyopathy (ARVC).BACKGROUND
Arrhythmogenic right ventricular cardiomyopathy is a myocardial disease, often familial, clinically characterized by the impending risk of ventricular arrhythmias and sudden death.METHODS
Thirty-seven ARVC families of northeast Italy were studied. Probands had a histologic diagnosis of ARVC, either at autopsy (19 families) or endomyocardial biopsy (18 families). Protocol of the investigation included basal electrocardiogram (ECG), 24-hour ECG, signal-averaged ECG, stress test and two-dimensional Doppler echocardiography. Invasive evaluation was performed when deemed necessary.RESULTSOf the 365 subjects, 151 (41%) were affected, 157 (43%) were unaffected, 17 (5%) were healthy carriers, and 40 (11%) were uncertain. Mean age at diagnosis was 31 ± 13 years. By echocardiography, 64% had mild, 30% had moderate, and 6% had severe form. Forty percent had ventricular arrhythmias, 49 were treated with antiarrhythmic drugs, and two were treated with implantable cardioverter defibrillators. Sport activity was restricted in all. Of the 28 families who underwent linkage analysis, 6 mapped to chromosome 14q23-q24, 4 to 1q42-q43, and 4 to 2q32.1-q32.3. No linkage with known loci was found in four families and 10 had uninformative results. During a follow-up of 8.5 ± 4.6 years, one patient died (0.08 patient/year mortality), and 15 developed an overt form of ARVC.CONCLUSIONS
Arrhythmogenic right ventricular cardiomyopathy is a progressive disease appearing during adolescence and early adulthood. Systematic evaluation of family members leads to early identification of ARVC, characterized by a broad clinical spectrum with a favorable outcome. In the setting of positive family history, even minor ECG and echocardiographic abnormalities are diagnostic.
Right ventricular pathologic involvement, with autopsy evidence of fibrous and fatty infiltration of the right ventricle, was investigated in numbers of families in which cases of juvenile sudden death had occurred. Seventy-two subjects from nine families were studied. Sixteen died at a young age and 56 are living. Postmortem investigation in 11 cases (mean age at death 24 years) revealed massive replacement of the right ventricular free wall by fat or fibrous tissue. In the 56 living patients clinical examination included an electrocardiogram (ECG) at rest, ambulatory ECG recording, posteroanterior and lateral chest roentgenograms, M-mode and two-dimensional echocardiograms and exercise stress tests. In 14 patients, hemodynamic, angiographic and electrophysiologic studies were also carried out; right ventricular endomyocardial biopsy was performed in four.Structural and dynamic right ventricular impairment was detected in 30 living patients (mean age 25 years), and concomitant mild left ventricular abnormalities were present in 4. In eight of the nine families studied at least two members were affected. Ventricular arrhythmias (Lown grade ≥4a) were recorded in more than half of the cases.The data reveal that right ventricular dysplasia shows a familial clustering and causes electrical instability that may place affected subjects at risk of sudden death. The mean age of these subjects suggests that the disease is manifested at a young age with a polymorphic clinical and arrhythmic profile. Finally, because this disease is a primary disorder of the ventricular myocardium, it should be included among the cardiomyopathies.
The frequency of right ventricular dysplasia (RVD) in an autopsy series of young persons with sudden cardiac death in the United States has not been previously reported. We reviewed the autopsies from cases of sudden cardiac deaths in young adults in the state of Maryland and noted three cases of RVD among 547 cardiac deaths (0.55%). These three cases of RVD in young adults and three additional cases from our file are presented. Their ages ranged from 19 to 28 yr, and there were five males and one female. Five deaths occurred during strenuous exercise while the sixth was unwitnessed. Three of these cases had a documented history of arrhythmias and 1 had palpitations. In each case, autopsy revealed right ventricular dilatation with partial absence of the myocardium and extensive fatty infiltrates with and without fibrosis. In four cases, collections of chronic lymphocytic infiltrates were seen, of which two had associated myocyte necrosis. In one patient, the disease was familial, while in the remaining five it was sporadic, suggesting a nongenetic cause.
Unlabelled:
Fifteen patients (mean age 30) presenting with right ventricular tachycardia (VT) of the outflow tract type (left bundle branch block with inferior axis morphology), in the absence of obvious organic heart disease, were studied. Seven patients had palpitations, one presyncope and seven were asymptomatic. The echo and/or angiographic findings were normal in 11 patients (73%), suggesting arrhythmogenic right ventricular dysplasia (ARVD) in three (20%) and dubious in one (7%). The VT was sustained in three patients (20%), nonsustained (11 +/- 6 beats) in twelve (80%), inducible during exercise in two out of 15 patients (13%) and with ventricular stimulation in one out of eight (12.5%). Four patients were treated with sotalol, three with Class IC drugs and one with amiodarone. At follow-up of 36 +/- 30 months, only three patients had VT recurrences due to drug withdrawal.
In conclusion:
(1) abnormal echo and/or angiographic findings suggested that ARVD was observed in a minority of the patients (22%); (2) the low inducibility of VT and the good response to sotalol suggested a possible mechanism of abnormal automaticity; and (3) at a 3-year follow-up the prognosis appeared to be good in both patients with or without echo-angiographic signs suggestive of right ventricular dysplasia.
Right ventricular dysplasia is characterized by an abnormality in the development of part of the right ventricular musculature. Patients with right ventricular dysplasia may present with ventricular tachycardia, suprgventricular arrhythmias, right-heart failure or asymptomatic cardlomegaly. Twenty-two adult patients with right ventricular dysplasia who had recurrent ventricular tachycardia were seen during a 7-year period. The male/female ratio was 2.7:1. The mean age at the time of hospitalization was 39 years. All but one of the patients had ventricular tachycardia of a left bundle branch block configuration. With few exceptions, the T waves were inverted over the right precordial leads. The heart was usually enlarged and the pulmonary vasculaturc was usually normal. In six patients who had two-dimensional echocardiograms, all showed increased right ventricular diastolic dimensions. All patients had right ventricular angiography; the diagnosis of right ventricular dysplasia was substantiated during surgery in 12 patients and at autopsy in another. Two other patients who did not have arrhythmias had right ventricular dysplasia diagnosed by right- and left-heart angiography.
Our unique experience, when combined with a literature review of 34 adult cases, permits a composite clinical profile of this condition in the adult.
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD) is a dominantly inherited disorder progressively affecting the myocardium and it is one of the major causes of juvenile sudden death. The chromosomal localization of the disease gene is reported here for the first time. A maximum lod score of 6.04 was obtained at theta = 0 for linkage with the polymorphic marker D14S42 (14q23-q24) in two families, one of which has 82 subjects (19 affected) in four generations. The pre-symptomatic identification of ARVD carriers by linkage analysis in the affected families strongly increases the possibility of prevention of life-threatening complications.
A time-domain signal-averaged ECG was performed in 52 patients with arrhythmogenic right ventricular dysplasia (ARVD) proven by angiography, in 45 control subjects with normal hearts, and in 132 patients with various types of ventricular arrhythmias and no evidence of cardiac disease during routine cardiac examination. Based on the results of control subjects, patients with at least 2/3 abnormal parameters (QRS > or = 113 ms, LAS > or = 38 ms, RMS 40 < or = 16 microV) were considered as having late potentials (LP). Prevalence of LP was 75% (39/52) in patients with ARVD, 19% (25/132) in patients with apparently idiopathic ventricular arrhythmias, and 4% (4/45) in controls (P < 0.01). In ARVD, no relationship was found between LP and age, type of ventricular arrhythmia (sustained or not), or extent of the disease on angiography. A significant correlation was found between the values of two parameters (QRS and LAS length) and the delay between the first ventricular arrhythmia and the examination (r = 0.39 and 0.42 respectively, P < 0.01). Further examinations (echo and/or angiography) revealed underlying heart disease in 26/132 patients with apparently normal hearts, including 13 with ARVD. LP were present in 21/26 patients (81%) with diseased heart vs 4/106 (4%) in those with normal hearts after complete examination, giving a sensitivity of 86%, and a specificity of 96% for detecting underlying heart disease. During a follow-up of 3.1 +/- 1.2 years after signal-averaged ECG, only one patient died from heart failure.(ABSTRACT TRUNCATED AT 250 WORDS)
Electron-beam computed tomography (CT) may be useful for detecting myocardial fat infiltration and diagnosing arrhythmogenic right ventricular dysplasia (ARVD). There are several characteristic electron-beam CT findings of ARVD. However, the incidence, their relation to electrophysiological abnormalities, and the usefulness of electron-beam CT for evaluating left ventricular involvement are unknown. This study aimed to clarify these issues.
Electron-beam CT was performed in 14 patients with ARVD (ARVD group), 16 age- and sex-matched patients with right ventricular enlargement and/or dysfunction without ARVD (RV enlargement group), and 13 control subjects (control group). The incidences of abnormal electron-beam CT findings in the three groups were examined. Furthermore, we examined the endocardial fat-infiltrated areas detected by electron-beam CT (CT-A) and electrophysiologically abnormal areas detected in the mapping electrophysiology study (EPS-A) and compared the relationship between them in the ARVD group. (1) The frequencies of abundant epicardial adipose tissue, low-attenuation trabeculations, scalloping of the right ventricular free wall, and intramyocardial fat deposits were 86%, 71%, 79%, and 50%, respectively, in the ARVD group, whereas these findings were not observed in the RV enlargement and control groups. (2) Three ARVD patients (21%) had adipose tissue involvement of the left ventricle. (3) The relationship between CT-A and EPS-A was as follows: CT-A > EPS-A, 71%; CT-A = EPS-A, 14%; and EPS-A only, 14%.
Characteristic electron-beam CT findings are frequently observed only in patients with ARVD. Electron-beam CT is useful for evaluating for left ventricular involvement and can estimate EPS-A.
Magnetic Resonance (MR) imaging gives information about the complex anatomy of the right ventricle (RV). Because of the capability of tissue characterization, in addition to the functional and morphologic analysis, MR imaging is an optimal technique to investigate patients (pts) with clinical suspicion of arrhythmogenic right ventricular dysplasia (ARVD).
The purpose of the current study was to investigate a group of 55 pts with ventricular arrhythmias in order to detect ARVD. MR was performed with a 0.5 magnet (MR MAX PLUS G:E. Medical System). Electrocardiographically gated spin-echo and gradient-echo MR images of the heart were obtained in both transverse and sagittal planes. Sustained ventricular tachycardia (SVT) was present in 14 pts, non sustained ventricular tachycardia (NSVT) in 13 pts, left bundle block ventricular premature complexes > 10000/24 h (VPC/LBB) in 28 pts. The abnormalities analyzed were: presence of focal or diffuse fatty replacement of myocardium, segmental or global dilation of the RV, reduction of ejection fraction with akinetic or dyskinetic areas, disarrangement of the trabecular pattern with the hypertrophy of the moderator band.
When intramyocardial fatty replacement and at least two of the abnormalities were present we considered the MR aspects compatible with the diagnosis of ARVD. We detected the presence of ARVD in 8/14 pts with SVT, in 4/13 pts with NSVT, in 4/28 pts VPC/LBB: In 10/16 pts with ARVD left ventricular abnormalities (areas of fatty replacement of the myocardial wall and/or reduction of ejection fraction) were also present. The left ventricular involvement was detected in 5 pts with SVT, in 2 pts with NSVT, in 3 pts with VPC/LBB: Even if in 31 pts it was not possible to identify aspects compatible with the diagnosis of ARVD, some structural abnormalities of RV were also present. Because of its non-invasiveness MR is an excellent technique for the detection of ARVD, and of minor right ventricular abnormalities.
Autosomal dominant arrhythmogenic right ventricular dysplasia (ARVD; MIM 107970) is a genetically heterogeneous cardiomyopathy, which often causes sudden death in juveniles and athletes. Two disease loci were previously mapped respectively to 14q23-q24 (ARVD1) and to 1q42-q43 (ARVD2). A third possible locus was assigned to 14q12-q22. We report here on a linkage study performed on three independent families with recurrence of ARVD characterized by localized involvement of the left ventricle. In these families the disease appears to be transmitted with three polymorphic DNA markers of the chromosome 2 long arm, showing a maximum lod score of 3.46 at theta = 0 for the marker D2S152. The multipoint linkage analysis suggests that the novel ARVD locus, provisionally named ARVD4, maps to 2q32. 1-q32.3, within the chromosomal region including markers D2S152, D2S103, and D2S389.
Arrhythmogenic right ventricular dysplasia (ARVD) is a poorly understood and often underdiagnosed disorder of the right ventricle, characterized by replacement of myocardium by fibroadipose tissue, arrhythmic manifestations, and sudden death. The disease occurs in families and is inherited as an autosomal dominant trait. This report describes five cases of ARVD identified by autopsy. In three of the cases, sudden death occurred in the young (16-28 years old) during or shortly after exercise. In another case, a 46-year-old man with no relevant medical history was found dead in his bathroom. In the last case, a 57-year-old woman died from pulmonary thromboembolism. In none of the subjects had the disease been diagnosed or suspected before death. Only one (a 21-year-old man) had previous typical symptoms of the disease. Autopsy examination showed right ventricle dilation and, in four cases, cardiomegaly. The right ventricular myocardium of all hearts was almost replaced by adipose tissue and to a variable degree by fibrous tissue, while the left ventricle myocardium demonstrated no, or only scattered, fibro-fatty infiltration. Postmortem diagnosis of ARVD can be important in identifying possible affected family members in order to initiate treatment.
Arrhythmogenic right ventricular dysplasia (ARVD) is a predisposing factor for sport-related cardiac arrest (CA), sudden cardiac death (SD), and life-threatening ventricular tachyarrhythmias (VT). The aim of this study was the assessment of athletes with ARVD, particularly the CA survivors. From 1974 to January 1996, 1642 competitive athletes (aver. 25.5 yr.), 136 of whom were top level athletes (TLA), were studied for important arrhythmic manifestations. All athletes underwent an individualised study protocol including a series of non invasive and invasive diagnostic techniques. One hundred and one athletes (90 males, 11 females, aver. 25.9 yr.) were diagnosed as being affected by ARVD on the basis of the WHO/ISFC criteria. The same percentage (about 6%) of ARVD is present in both the general arrhythmic athletes population and in the subgroup of TLA. Prevalence of ARVD among athletes with CA or SD is high (respectively 23% and 25%), confirming the observation that ARVD is one of the major causes of SD in Italian athletes. All CA were athletic activity related, indicating the potentiality of exercise as a cause of electrical destabilisation in subjects with ARVD. In athletes with documented ARVD intense sport activity has to be proscribed. In athletes at risk of CA or SD an aggressive treatment, ICD implantation and RF catheter ablation must be taken into consideration.
Arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C) is a heart muscle disease characterized by peculiar RV involvement and electrical instability that precipitates ventricular arrhythmias and sudden death. The purpose of the present consensus report of the Study Group on ARVD/C of the Working Groups on Myocardial and Pericardial Disease and Arrhythmias of the European Society of Cardiology and of the Scientific Council on Cardiomyopathies of the World Heart Federation is to review the considerable progress in our understanding of the etiopathogenesis, morbid anatomy, and clinical presentation of ARVD/C since it first was described in 1977. The present article focuses on important but still unanswered issues, mostly regarding risk stratification, clinical outcome, and management of affected patients. Because ARVD/C is relatively uncommon and any one center may have experience with only a few patients, an international registry is being established to accumulate information and enhance the numbers of patients that can be analyzed and thus answer pending questions. The registry also will facilitate pathological, molecular, and genetics research on the causes and pathogenesis of the ARVD/C. Furthermore, availability of an international database will enhance awareness of this largely unrecognized condition among the medical community. Physicians are encouraged to enroll patients in the International Registry of ARVD/C.
We reevaluated the magnetic resonance (MR) examinations of 38 healthy volunteers (control group, CG) and of 124 patients with RV arrhythmia with left bundle branch block (LBBB) morphology: 45 with episodes of RV sustained tachycardia and of polymorphic RV premature beats (RVST-PPB group); 36 with only RV outflow tract sustained or not sustained tachycardia (RVOTT group); 43 with RV monomorphic premature beats (RVMPB group). All the examinations were reevaluated in a blinded fashion for detecting myocardial adipose replacement (AR) and wall bulges or aneurysms. In RVST-PPB patients, no AR was observed in 9%; 1 RV region involvement, 0%; 2 regions, 4%; > or = 3 regions, 87%; left ventricle (LV), 15%. RVOTT patients: 28%, 53%, 14%, 5%, and 0% [corrected], respectively. RVMPB patients: 33%, 46%, 19%, 2%, and 0% [corrected], respectively. In CG, AR was observed in 11% (in RV outflow tract), RV bulges were detected in 75% [corrected] of RVST-PPB, 39% of RVOTT, and 14% of RVMPB patients, none of the CG; RV aneurysms in 33% of RVST-PPB patients, none of RVOTT patients, RVMBP patients, and CG. A significant difference among groups for RV and LV AR as well as RV bulges and aneurysms was found (p < 0.0001). In the direct comparisons, significant differences were found for: disease duration (RVST-PPB vs. RVMPB, p = 0.0396); RV AR (all the patients groups vs. CG, RVST-PPB vs. RVOTT or RVMPB, p < 0.0001); RV aneurysms (RVST-PPB vs. CG, RVST-PPB vs. RVOTT or RVMPB, p < 0.0002); bulges (all comparisons, p < 0.0174). AR is confirmed as a structural substrate in RV arrhythmias. Number and extension of MR abnormalities are correlated to different degrees of RV arrhythmias.
Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown cause that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. Clinical manifestations include structural and functional malformations of the right ventricle, electrocardiographic abnormalities, and presentation with ventricular tachycardias with left bundle branch pattern or sudden death. The disease is often familial with an autosomal inheritance. In addition to right ventricular dilatation, right ventricular aneurysms are typical deformities of ARVD and they are distributed in the so-called "triangle of dysplasia", i.e., right ventricular outflow tract, apex, and infundibulum. Ventricular aneurysms at these sites can be considered pathognomonic of ARVD. Another typical hallmark of ARVD is fibrofatty infiltration of the right ventricular free wall. These functional and morphologic characteristics are relevant to clinical imaging investigations such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and magnetic resonance imaging (MRI). Among these techniques, MRI allows the clearest visualization of the heart, in particular because the right ventricle is involved, which is usually more difficult to explore with the other imaging modalities. Furthermore, MRI offers the specific advantage of visualizing adipose infiltration as a bright signal of the right ventricular myocardium. MRI provides the most important anatomic, functional, and morphologic criteria for diagnosis of ARVD within one single study. As a result, MRI appears to be the optimal imaging technique for detecting and following patients with clinical suspicion of ARVD.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a myocardial disease, often familial, that is characterized by fibro-fatty replacement of the right ventricular (RV) myocardium. The most common clinical manifestations of ARVC consists of ventricular arrhythmias of RV origin, which may lead to sudden death mostly in young people and athletes, electrocardiograph depolarization/repolarization changes mostly localized to right precordial leads, and global and/or regional dysfunction and structural alterations of the RV. The diagnosis of ARVC may be difficult due to several problems with the specificity of the electrocardiograph abnormalities, the different potential etiologies of ventricular arrhythmias with a left bundle branch morphology, the assessment of the RV structure and function, and the interpretation of endomyocardial biopsy findings. Therefore, standardized diagnostic criteria have been proposed by the Study Group on ARVC of the European Society of Cardiology. According to these guidelines, the diagnosis of ARVC is based on the presence of major and minor criteria encompassing electrocardiograph, arrhythmic, morphofunctional, histopathologic, and genetic factors. Because the assessment of sudden death risk in patients with ARVC is still not well established, there are no precise guidelines to determine which are the patients who need to be treated and which is the best management approach. The therapeutic options include beta blockers, antiarrhythmic drugs, catheter ablation, and implantable cardioverter defibrillator. The implantable defibrillator is the most effective safe-guard against arrhythmic sudden death. However, its precise role in changing natural history of ARVC by preventing sudden and nonsudden death needs to be evaluated by a prospective study of a large series of patients. In patients in whom ARVC has progressed to severe RV or biventricular systolic dysfunction with risk of thromboembolic complications, treatment consists of current therapy for heart failure including anticoagulant therapy. In case of refractory congestive heart failure, the patients may become candidates for heart transplantation.
Arrhythmogenic right ventricular displasia (ARVD) is a heart disease characterized by a total or partial fat replacement of the myocardium. Echocardiography, which has been most commonly used for the diagnosis of ARVD, usually only demonstrates right ventricular enlargement with associated hypokinesia and with normal left ventricular chamber size. Angiocardiography is very effective in the evaluation of ARVD, especially, in the detection of wall motion abnormalities and bulgings. However, angiocardiography is invasive. Magnetic resonance imaging is a non-invasive, repeatable technique, which allows a more accurate evaluation of the right ventricular chamber and free wall. Therefore MRI is very effective in the differentiation of the high signal intensity of the fat from other medium intensity tissue, such as muscle, and in detection of fibro-fatty replacement of myocardium. It provides an accurate assessment of right-chamber enlargement, right ventricle outflow tract ectasia and wall motion abnormalities by cine-MR GE technique.
Arrhythmogenic right ventricular dysplasia (ARVD/C) is one cause of death in young adults in the United States, representing approximately 17% of all ARVD/C cases reported. This study presents 2 cases of ARVD/C diagnosed at a central Texas hospital and reviews the literature regarding this disease. The diagnosis, histology, presentation, prognosis, and therapy are addressed because the rare nature of this disease within the United States makes diagnosis and treatment difficult and creates problems of adaptation for the patient. Clinicians must become more familiar with this potentially fatal cardiac disorder that can create vulnerability within a young adult population.
We sought to ascertain the prevalence and mode of expression of familial disease in a consecutive series of patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D).
Autosomal-dominant inheritance is recognized in ARVC. The prevalence and mode of expression of familial disease in consecutive, unselected families is uncertain.
First- and second-degree relatives of 67 ARVC index patients underwent cardiac evaluation with history and examination, 12-lead and signal-averaged electrocardiogram (ECG), two-dimensional and Doppler echocardiography, metabolic exercise testing and Holter monitoring. Diagnoses were made in accordance with published criteria.
Of 298 relatives, 29 (10%; mean age 37.4 +/- 16.4 years) had ARVC. These were from 19 of the 67 families, representing familial involvement in 28%. Of these affected relatives, 72% were asymptomatic, 17% had ventricular tachycardia (sustained VT 10%, nonsustained VT 7%) and 21% had left ventricular involvement. A further 32 relatives (11%; 37.7 +/- 12.4 years) exhibited nondiagnostic ECG, echocardiographic or Holter abnormalities. Fifteen of these relatives were from families with only the proband affected, and inclusion of this subset of relatives would have resulted in familial ARVC in 48% of index cases. Four additional relatives (1% to 3%) fulfilled diagnostic criteria for dilated cardiomyopathy without any features of right ventricular disease.
By using current diagnostic criteria, familial disease was present in 28% of index patients. A further 11% of their relatives had minor cardiac abnormalities, which, in the context of a disease whose mode of inheritance is autosomal dominant, are likely to represent early or mild disease expression. We advocate that the current ARVC diagnostic criteria are modified to reflect the broader spectrum of disease that is observed in family members.
Magnet resonance imaging (MRI) findings in patients meeting Task Force criteria for the diagnosis of arrhythmogenic right ventricular dysplasia (ARVD) have not been systematically described. We report qualitative and quantitative MRI findings in ARVD using state-of-the-art MRI.
MRI was performed on 12 patients with ARVD who were prospectively diagnosed using the Task Force criteria. The imaging protocol included breath-hold double inversion recovery spin-echo and gradient-echo images. Ventricular volumes and dimensions were compared to 10 age- and sex-matched normal volunteers. High intramyocardial T1 signal similar to fat signal was observed in 9 (75%) of the 12 patients and in none of the controls. Right ventricular (RV) hypertrophy was seen in 5 (42%) patients, trabecular disarray in 7 (59%), and wall thinning in 3 (25%). Both the RV end-diastolic diameter and the outflow tract area were significantly higher in ARVD patients compared to controls (51.2 vs 43.2 mm, P < 0.01; and 14.5 vs 9.3 cm2, P < 0.01, respectively). ARVD patients had a higher RV end-diastolic volume index and lower RV ejection fraction compared with controls (127.4 vs 87.5, P < 0.01; and 41.6% vs 57%, P < 0.01, respectively).
High intramyocardial T1 signal indicative of fat is seen in a high percentage (75%) of patients who meet the Task Force criteria for ARVD. Trabecular disarray is seen more frequently than wall thinning and aneurysms. RV dimensions and volumes differ significantly in ARVD compared to controls, indicating a role for quantitative evaluation in the diagnosis of ARVD.
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a relatively newly recognized disease. A clinical profile of patients with this condition was first published in 1982.1 In that report, it was observed that the majority of patients were male. Patients presented with ventricular tachycardia of left bundle-branch block morphology. An enlarged right ventricle due to fibrofatty infiltration of the right ventricular free wall and a familial association were noted. It was considered to be a rare disease of unknown cause. Since then, it has been diagnosed with increasing frequency and has been reported to account for 3% to 5% of unexplained sudden cardiac death under the age of 65 years.2,3 Evidence of the disease is found in 30% to 50% of family members who are studied by noninvasive tests, including ECG, echocardiography, and signal-averaged ECG.4,5 It has been suggested that MRI may also be used for diagnostic purposes, but this remains controversial.6,7 Six genetic loci have been reported to be associated with ARVD/C, and 3 genes have been identified: ryanodine receptor (RyR2),8 plakoglobin (JUP),9and desmoplakin (DSM).10 There is autosomal dominant transmission with all the genetic forms except Naxos disease8 and Carvahal syndrome,11 both of which have autosomal recessive transmission. These 2 autosomal recessive disorders are variants of ARVD/C that are associated with skin and hair abnormalities. The cardiac presentation in Carvahal syndrome is that of a left ventricular cardiomyopathy and arrhythmias.
With the recognition that ARVD/C is frequently familial and can cause arrhythmic death, the clinical challenge is how to definitively identify individuals with ARVD/C who have mild or minimal structural abnormalities of the right ventricle. Definite identification of minimal structural abnormalities of the right ventricle can be difficult because of the irregular shape and asymmetrical contractile pattern …
The natural history of arrhythmogenic right ventricular cardiomyopathy is determined by the electrical instability of the dystrophic myocardium, which can precipitate arrhythmic cardiac arrest any time during the course of the disease and by the progressive myocardial loss that results in ventricular dysfunction and heart failure. Sudden death accounts for the majority of the fatal events but its occurrence is mostly unpredictable. There are no prospective and controlled studies assessing clinical markers that can predict the occurrence of life-threatening ventricular arrhythmias. However, the noninvasive risk profile, which emerges from retrospective analysis of clinical and pathologic series, is characterized by history of syncope, physical exercise, spontaneous ventricular tachycardia or ventricular fibrillation, right ventricular dysfunction, left ventricular involvement, right precordial negative T wave, right bundle branch block, QT-QRS dispersion, right precordial ST-segment elevation and late potentials. At present only QRS dispersion, history of syncope and right and/or left ventricular abnormalities at radionuclide angiography proved to be independent noninvasive predictors of sudden death.
Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by progressive replacement of RV myocardium with fibro-adipose tissue thought to be responsible for the presence of late potentials (LP) detected by SAECG. The general consensus on the role of SAECG in the diagnosis and prognosis of patients with ARVD is lacking. The purpose of this systematic review was to better define the role of SAECG in ARVD.
An extensive review of literature was done to specifically describe the prevalence of LP in ARVD and its determinants, explore the various options available to improve the diagnostic ability of SAECG, and provide recommendations for proper utilization of this technique.
LPs are frequent in ARVD (47-100%), and more prevalent in severe disease and in patients with documented spontaneous VT. SAECG is a useful test in following the characteristic evolutivity of the disease. 4-16% of normal family members of patients with ARVD also have abnormal SAECG results. Detection of LP in ARVD can be improved by employing a high-pass filter of 25 Hz and specifically looking for changes in the Z leads.
SAECG testing should be considered a standard part of the evaluation of patients with known or suspected ARVD. Further research is needed to confirm the value of SAECG testing in predicting arrhythmia risk and assessing the rate of disease progression, as well as to determine if greater prevalence of SAECG abnormalities in family members of patients with ARVD represents early detection of ARVD. The ongoing multidisciplinary study of right ventricular dysplasia will hopefully answer some of these questions.
DanieliGA:ARVD4,anewlocusforarrhyth-mogenicrightventricularcardiomyopathy,mapstochromosome2long arm
- A Rampazzo
- A Nava
- M Miorin
- P Fonderico
- B Pope
- N Tiso
- B Livolsi
- Zimbellor
Rampazzo A, Nava A, Miorin M, Fonderico P, Pope B, Tiso N, Livolsi B,ZimbelloR,ThieneG,DanieliGA:ARVD4,anewlocusforarrhyth-mogenicrightventricularcardiomyopathy,mapstochromosome2long arm. Genomics 1997;15;45:259-263
LagallaR:MRimag-ingofarrhythmogenicrightventriculardysplasia
- Brancatom
- Hoffmanne
- Indovinag
- Mariamd
BrancatoM,HoffmannE,IndovinaG,MariaMD,LagallaR:MRimag-ingofarrhythmogenicrightventriculardysplasia.IntJCardiovascImag-ing 2001;17:297-304