Article

MR imaging of arrhythmogenic right ventricular cardiomyopathy: Morphologic findings and interobserver reliability

Uppsala University, Uppsala, Uppsala, Sweden
Cardiology (Impact Factor: 2.04). 01/2003; 99(3):153-62. DOI: 10.1159/000070672
Source: PubMed

ABSTRACT 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.
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.
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).
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.

Full-text

Available from: Richard D White, Aug 19, 2014
0 Followers
 · 
107 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Assessment of cardiac right-ventricle functions plays an essential role in diagnosis of arrhythmogenic right ventricular dysplasia (ARVD). Among clinical tests, cardiac magnetic resonance imaging (MRI) is now becoming the most valid imaging technique to diagnose ARVD. Fatty infiltration of the right ventricular free wall can be visible on cardiac MRI. Finding right-ventricle functional parameters from cardiac MRI images contains segmentation of right-ventricle in each slice of end diastole and end systole phases of cardiac cycle and calculation of end diastolic and end systolic volume and furthermore other functional parameters. The main problem of this task is the segmentation part. We used a robust method based on deformable model that uses shape information for segmentation of right-ventricle in short axis MRI images. After segmentation of right-ventricle from base to apex in end diastole and end systole phases of cardiac cycle, volume of right-ventricle in these phases calculated and then, ejection fraction calculated. We performed a quantitative evaluation of clinical cardiac parameters derived from the automatic segmentation by comparison against a manual delineation of the ventricles. The manually and automatically determined quantitative clinical parameters were statistically compared by means of linear regression. This fits a line to the data such that the root-mean-square error (RMSE) of the residuals is minimized. The results show low RMSE for Right Ventricle Ejection Fraction and Volume (≤ 0.06 for RV EF, and ≤ 10 mL for RV volume). Evaluation of segmentation results is also done by means of four statistical measures including sensitivity, specificity, similarity index and Jaccard index. The average value of similarity index is 86.87%. The Jaccard index mean value is 83.85% which shows a good accuracy of segmentation. The average of sensitivity is 93.9% and mean value of the specificity is 89.45%. These results show the reliability of proposed method in these cases that manual segmentation is inapplicable. Huge shape variety of right-ventricle led us to use a shape prior based method and this work can develop by four-dimensional processing for determining the first ventricular slices.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We sought to evaluate the effect of application of the revised 2010 Task Force Criteria (TFC) on the prevalence of major and minor Cardiovascular Magnetic Resonance (CMR) criteria for Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) versus application of the original 1994 TFC. We also assessed the utility of MRI to identify alternative diagnoses for patients referred for ARVC evaluation.
    Journal of Cardiovascular Magnetic Resonance 07/2014; 16(1):47. DOI:10.1186/1532-429X-16-47 · 5.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is one of the most arrhythmogenic forms of inherited cardiomyopathy and a frequent cause of sudden death in the young. Affected individuals typically present between the second and fourth decade of life with arrhythmias coming from the right ventricle. Pathogenic mutations in genes encoding the cardiac desmosome can be found in approximately 60% of index patients, leading to our current perception of ARVC as a desmosomal disease. Although ARVC is known to preferentially affect the right ventricle, early and/or predominant left ventricular involvement is increasingly recognized. Diagnosis is made by combining multiple sources of diagnostic information as prescribed by the "Task Force" criteria. Recent research suggests that electrical abnormalities precede structural changes in ARVC. Cardiovascular Magnetic Resonance (CMR) is an ideal technique in ARVC workup, as it provides comprehensive information on cardiac morphology, function, and tissue characterization in a single investigation. Prevention of sudden cardiac death using implantable cardioverter-defibrillators is the most important management consideration. This purpose of this paper is to provide an updated review of our understanding of the genetics, diagnosis, current state-of-the-art CMR acquisition and analysis, and management of patients with ARVC.
    Journal of Cardiovascular Magnetic Resonance 07/2014; 16(1):50. DOI:10.1186/s12968-014-0050-8 · 5.11 Impact Factor