[Show abstract][Hide abstract] ABSTRACT: Still increasing life expectancy for patients with implanted devices : and with large number of leads more and more often induces the need to cure the treatment complications or to change especially to CRT therapy. In order to prevent further complications, the possibility of damaged or redundant leads extraction should be taken into consideration. The aim of the paper was to assess the effectiveness and safety of transvenous lead extraction with co-implantation of resynchronization systems.
[Show abstract][Hide abstract] ABSTRACT: The benefits of rehabilitation in heart failure (HF) patients are well established. Little is known about Nordic walking (NW) training in HF patients especially in those with cardiovascular implantable electronic devices (CIEDs).
European Journal of Preventive Cardiology 09/2014; · 3.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose
Effectiveness of implantable defibrillators (ICD) has been proven with large randomized trials. Unfortunately, ICD discharge is painful and potentially threatening for the patient despite its life saving effects. We analyzed influence of the clinical parameters present before implantation on the effectiveness of antitachycardia pacing therapy (ATP) in terminating ventricular tachycardia (VT) slower than 200 bpm in the coronary artery disease patients with prophylactic implanted ICD in a single centre retrospective trial.
We analyzed 121 consecutive coronary disease patients with ICD implanted in primary prophylaxis between 2001 and 2007, with the mean age of 62 ± 10 years. The mean follow-up was 876 ± 538 days.
32 of them had VT. In 27 persons (84.4%) at least one ATP attempt terminate VT. ATP was always successful in 21 patients. We analyzed age, sex, LVEF, NYHA class, widening of QRS complex, atrial fibrillation, type of myocardial infarction or diabetes. There were no significant differences in clinical features between patients with successful and unsuccessful ATP therapy.
High effectiveness of ATP was shown in this group. There were no clinical factors indicating success of this type of therapy. That could justify programming ATP as the first line therapy in the VT zone in primary prophylaxis coronary artery disease patients to reduce application of shock therapy.
It should be possible to apply a single mode of programming when discharging patients after the implantation procedure regardless of the patient's clinical condition. This could help to control and programme the devices, thus reducing the risk of errors.
Advances in Medical Sciences 09/2014; · 0.80 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Radiofrequency catheter ablation (RFCA) has been increasingly used for treatment of patients with symptomatic atrial fibrillation (AF). Our study aimed to identify simple pre-procedural success predictors of RFCA in patients with AF.
[Show abstract][Hide abstract] ABSTRACT: Over the last 10 years, there has been an increasing number of patients with pacemaker (PM) and cardioverter-defibrillator (ICD). This study is a retrospective analysis of indications for endocardial pacemaker and ICD lead extractions between 2003 and 2009 based on the experience of three Polish Referral Lead Extraction Centers.
Archives of Medical Science 05/2014; 10(2):258-65. · 1.89 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In December 2010 St. Jude Medical informed about higher incidence of silicone insulation abrasion in implantable cardioverter-defibrillator leads Riata/Riata ST. The manifestation of this phenomenon is the externalisation of conductors outside the body of the lead, which is visible in a fluoroscopy. The abrasion could also involve an insulation under high-voltage coil and in the worst case could result in a short circuit within high voltage part of the system. The incidence of this phenomenon varies from part of to several dozen percent according to published papers and becomes higher in a longer follow-up. The highest probability of malfunction in 8 F single coil and the lowest in 7 F dual-coil leads is observed. For the needs of this guidelines all Riata/Riata ST leads were divided into: functioning, damaged but active (visible externalisation but electrically functioning), malfunctioning. In the last case the lead should be removed and a new one implanted (class of indication I) ,although only implantation of a new lead with abandoning malfunctioning one is allowed and should be considered (IIa). In patients with functioning lead extraction with a new lead implantation may be considered during elective replacement only in high risk patients (IIb). In case of damaged but active lead its extraction with the implantation of a new lead during elective replacement of the device should be considered in high risk population (IIa) and may be considered in other patients (IIb). The final decision related to Riata/Riata ST should be individualised and undertaken in co-operation with the patient after detailed assessment of the risk related to each treatment option.
Kardiologia polska 01/2014; 72(6):576-82. · 0.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The paper presents a diagnostic algorithm for classifying cardiac tachyarrhythmias for implantable cardioverter defibrillators (ICDs). The main aim was to develop an algorithm that could reduce the rate of occurrence of inappropriate therapies, which are often observed in existing ICDs. To achieve low energy consumption, which is a critical factor for implantable medical devices, very low computational complexity of the algorithm was crucial. The study describes and validates such an algorithm and estimates its clinical value.
The algorithm was based on the heart rate variability (HRV) analysis. The input data for our algorithm were: RR-interval (I), as extracted from raw intracardiac electrogram (EGM), and in addition two other features of HRV called here onset (ONS) and instability (INST). 6 diagnostic categories were considered: ventricular fibrillation (VF), ventricular tachycardia (VT), sinus tachycardia (ST), detection artifacts and irregularities (including extrasystoles) (DAI), atrial tachyarrhythmias (ATF) and no tachycardia (i.e. normal sinus rhythm) (NT). The initial set of fuzzy rules based on the distributions of I, ONS and INST in the 6 categories was optimized by means of a software tool for automatic rule assessment using simulated annealing. A training data set with 74 EGM recordings was used during optimization, and the algorithm was validated with a validation data set with 58 EGM recordings. Real life recordings stored in defibrillator memories were used. Additionally the algorithm was tested on 2 sets of recordings from the PhysioBank databases: MIT-BIH Arrhythmia Database and MIT-BIH Supraventricular Arrhythmia Database. A custom CMOS integrated circuit implementing the diagnostic algorithm was designed in order to estimate the power consumption. A dedicated Web site, which provides public online access to the algorithm, has been created and is available for testing it.
The total number of events in our training and validation sets was 132. In total 57 shocks and 28 antitachycardia pacing (ATP) therapies were delivered by ICDs. 25 out of 57 shocks were unjustified: 7 for ST, 12 for DAI, 6 for ATF. Our fuzzy rule-based diagnostic algorithm correctly recognized all episodes of VF and VT, except for one case where VT was recognized as VF. In four cases short lasting, spontaneously ending VT episodes were not detected (in these cases no therapy was needed and they were not detected by ICDs either). In other words, a fuzzy logic algorithm driven ICD would deliver one unjustified shock and deliver correct therapies in all other cases. In the tests, no adjustments of our algorithm to individual patients were needed. The sensitivity and specificity calculated from the results were 100% and 98%, respectively. In 126 ECG recordings from PhysioBank (about 30min each) our algorithm incorrectly detected 4 episodes of VT, which should rather be classified as fast supraventricular tachycardias. The estimated power consumption of the dedicated integrated circuit implementing the algorithm was below 120nW.
The paper presents a fuzzy logic-based control algorithm for ICD. Its main advantages are: simplicity and ability to decrease the rate of occurrence of inappropriate therapies. The algorithm can work in real time (i.e. update the diagnosis after every RR-interval) with very limited computational resources.
Artificial intelligence in medicine 12/2013; · 1.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The increasing number of patients (pts) with cardiac implantable electronic devices (CIEDs) causes a rise in the absolute percentage of individuals qualifying for a transvenous lead extraction (TLE) due to infectious, vascular or lead failure related indications. As the survival time prolongs, TLE procedures more and more often concern the electrodes of long-term functioning Authors provide the retrospective analysis of the effectiveness and safety of TLE performed on leads implanted at least 10 years before the extraction.
Between 2008 - 2012 we performed TLE of 364 electrodes in 217 pts. Out of these, 66 (18.1%) leads in 43 (19.8%) pts had been implanted for at least 10 years. The mean dwelling time for electrodes was 161 months (120 to 330). In 62% cases CIED-related infection was an indication for TLE. The following extracting techniques were used: manual direct traction, device traction, mechanical telescopic sheaths, autorotational cutting sheaths and femoral approach.
58 pacemaker and 8 defibrillating leads were extracted. 63 (95%) completely , in the remain 3 cases the clinical success was achieved with the small portion of the lead left into the vascular space. No major procedure complications were observed; minor complications were found in 3 pts (6%).
Transvenous lead extraction with the use of various endovascular techniques is an effective and safe method for treating infectious, vascular and mechanical complications of long-lasting CIEDs therapy.
[Show abstract][Hide abstract] ABSTRACT: The aim of the study was to analyze the value of a completely new fuzzy logic-based detection algorithm (FA) in comparison with arrhythmia classification algorithms used in existing ICDs in order to demonstrate whether the rate of inappropriate therapies can be reduced.
On the basis of the RR intervals database containing arrhythmia events and controls recordings from the ICD memory a diagnostic algorithm was developed and tested by a computer program. This algorithm uses the same input signals as existing ICDs: RR interval as the primary input variable and two variables derived from it, onset and stability. However, it uses 15 fuzzy rules instead of fixed thresholds used in existing devices. The algorithm considers 6 diagnostic categories: (1) VF (ventricular fibrillation), (2) VT (ventricular tachycardia), (3) ST (sinus tachycardia), (4) DAI (artifacts and heart rhythm irregularities including extrasystoles and T-wave oversensing-TWOS), (5) ATF (atrial and supraventricular tachycardia or fibrillation), and 96) NT (sinus rhythm). This algorithm was tested on 172 RR recordings from different ICDs in the follow-up of 135 patients.
All diagnostic categories of the algorithm were present in the analyzed recordings: VF (n = 35), VT (n = 48), ST (n = 14), DAI (n = 32), ATF (n = 18), NT (n = 25). Thirty-eight patients (31.4%) in the studied group received inappropriate ICD therapies. In all these cases the final diagnosis of the algorithm was correct (19 cases of artifacts, 11 of atrial fibrillation and 8 of ST) and fuzzy rules algorithm implementation would have withheld unnecessary therapies. Incidence of inappropriate therapies: 3 vs. 38 (the proposed algorithm vs. ICD diagnosis, respectively) differed significantly (p < 0.05). VT/VF were detected correctly in both groups. Sensitivity and specificity were calculated: 100%, 97.8%, and 100%, 72.9% respectively for FA and tested ICDs recordings (p < 0.05).
Diagnostic performance of the proposed fuzzy logic based algorithm seems to be promising and its implementation could diminish ICDs inappropriate therapies. We found FA usefulness in correct diagnosis of sinus tachycardia, atrial fibrillation and artifacts in comparison with tested ICDs.
Annals of Noninvasive Electrocardiology 09/2013; 18(5):457-66. · 1.08 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: LMNA mutations are most frequently involved in the pathogenesis of dilated cardiomyopathy with conduction disease. The goal of this study was to identify LMNA mutations, estimate their frequency among Polish dilated cardiomyopathy patients and characterize their effect both in vivo and in vitro. METHODS: Between January, 2008 and June, 2012 two patient populations were screened for the presence of LMNA mutations by direct sequencing: 66 dilated cardiomyopathy patients including 27 heart transplant recipients and 39 dilated cardiomyopathy patients with heart failure referred for heart transplantation evaluation, and 44 consecutive dilated cardiomyopathy patients, referred for a family evaluation and mutation screening. RESULTS: We detected nine non-synonymous mutations including three novel mutations: p.Ser431*, p.Val256Gly and p.Gly400Argfs*11 deletion. There were 25 carriers altogether in nine families. The carriers were mostly characterized by dilated cardiomyopathy and heart failure with conduction system disease and/or complex ventricular arrhythmia, although five were asymptomatic. Among the LMNA mutation carriers, six underwent heart transplantation, fourteen ICD implantation and eight had pacemaker. In addition, we obtained ultrastructural images of cardiomyocytes from the patient carrying p.Thr510Tyrfs*42. Furthermore, because the novel p.Val256Gly mutation was found in a sporadic case, we verified its pathogenicity by expressing the mutation in a cellular model. CONCLUSIONS: In conclusion, in the two referral centre populations, the screening revealed five mutations among 66 heart transplant recipients or patients referred for heart transplantation (7.6%) and four mutations among 44 consecutive dilated cardiomyopathy patients referred for familial evaluation (9.1%). Dilated cardiomyopathy patients with LMNA mutations have poor prognosis, however considerable clinical variability is present among family members.
BMC Medical Genetics 05/2013; 14(1):55. · 2.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Venous occlusion is a relatively common complication of endocardial lead implantation. It may cause a critical problem when implantation of a new lead is needed. Traditional methods result in leaving abandoned leads. The optimal approach seems to be the extraction of the damaged or abandoned lead, regaining venous access and implantation of a new lead.
To assess the efficacy and safety of new lead implantation by the method of lead extraction.
All transvenous lead extraction procedures (203 patients) between 1 August 2008 and 15 October 2012 were assessed. The analysis included cases with leads implanted for at least 6 months prior to extraction.
Regaining venous access was the main indication for lead extraction in 5 patients (4.9%). The reason for new lead implantation was lead damage (n = 7) and system up-grade to cardiac resynchronization therapy (CRT) (n = 3). In total, 23 leads were extracted (9 defibrillation leads, 12 pacing leads and 2 left ventricular leads). The mean time from the implantation was 92.2 ±43.2 (48-152) months. In all cases Cook mechanical sheaths were applied. The use of the Evolution system was necessary to extract 3 leads. In all cases the new leads were successfully implanted as planned. No serious complications occurred.
Diagnosis of venous occlusion should not be a contraindication for ipsilateral implantation of the new lead, because the techniques of transvenous lead extraction enable successful regaining of venous access.
Postepy w Kardiologii Interwencyjnej / Advances in Interventional Cardiology 01/2013; 9(1):16-21. · 0.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An increasing number of patients is referred for orthotopic heart transplantation (OHT) after previous implantable cardioverter-defibrillator (ICD) or cardiac resynchronisation therapy (CRT) device implantation.
To assess the rate of unsuccessful lead extractions during OHT and propose an appropriate management algorithm. Methods: The study population included 73 consecutive patients who underwent OHT in our hospital between January 2009 and December 2011.
In the study group, 36 (49.3%) patients previously underwent ICD (21 patients, 28.8%) or CRT (15 patients, 20.5%) implantation. In 29 patients, all previously implanted leads were completely removed during transplantation. In 7 (19.5%) patients, fragments of the leads could not be removed and were abandoned due to their adherence to the venous system, including a proximal defibrillation coil in 6 cases and a fragment of a left ventricular lead in 1 case. All abandoned lead fragments were extracted after the transplantation (10-70 days, mean 27 days) either with manual traction techniques (1 case, left ventricular lead), or with the assistance of lead extraction sheaths (6 cases, dual-coil defibrillation leads). Due to lead fracture, it was necessary to use femoral approach in 1 case. No complications of lead extraction were noted.
In a significant number of patients, previously implanted leads cannot be removed during OHT. Therefore, abandoned lead fragments should be removed after the transplantation using transvenous lead extraction techniques.
Kardiologia polska 01/2013; 71(2):159-63. · 0.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM) is generally associated with deterioration of the clinical status, functional capacity, and quality of life. It is also an independent risk factor for stroke and death. Studies evaluating the effectiveness of AF ablation in this cohort are relatively scant, have included relatively few patients, and their results are somewhat conflicting. Thus, the aim of this study was to assess the safety and efficacy of catheter ablation of AF in patients with HCM.
Thirty patients (10 females; mean age 48.7 ± 11 years) with drug-refractory paroxysmal (n = 14), persistent (n = 7), or long-persistent (> 1 year; n = 9) AF were prospectively recruited into the study. Eleven patients were in New York Heart Association (NYHA) class I, 13 patients were in NYHA class II, and 6 patients were in NYHA class III. Mean atrial volume was 180 ± 47 mL, interventricular septum thickness was 20.5 ± 6.3 mm, and left atrial area was 29.8 ± 6.2 cm2. Ablation protocol was adjusted to the clinical and electrophysiological status of the patients. Pulmonary vein isolation and bidirectional cavo-tricuspid isthmus block were performed in all patients. In addition, left atrial linear lesions were created and complex fragmented atrial potentials were ablated in patients with persistent and long-persistent AF, as well as during repeated procedures.
At 12 months, stable sinus rhythm (SR) was present in 16 (53%) patients, significantly more frequently in patients with paroxysmal AF (71% in SR) compared to those with persistent (57.1% in SR) or long-persistent (22% in SR) AF. A significant reduction of AF burden was observed in 85.7% of patients with paroxysmal AF, 71.4% of patients with persistent AF, and 55.5% of patients with long-persistent AF. Single procedure success rate was 33% (10 patients), and repeat ablation procedures were performed in 13 patients. No periprocedural complications occurred. Thromboembolic events were noted in 2 patients with arrhythmia recurrence during the follow-up, including stroke in 1 patient and peripheral embolism in the other patient. In both these patients, heart failure worsening was observed during these events, and anticoagulation was inadequate in one of them. Five of 16 patients in whom stable SR was observed during the follow-up were off antiarrhythmic drug therapy at final evaluation. In the other 6 patients, antiarrhythmic drug therapy was continued due to ventricular arrhythmias. Successfully treated patients more often had paroxysmal AF (successful ablation: paroxysmal AF in 10 of 16 patients; unsuccessful ablation: paroxysmal AF in 4 of 14 patients; p = 0.009) and were younger (45 ± 11.5 years vs. 52.6 ± 9.2 years; p = 0.046). In addition, a trend toward a reduced need for cardioversion at the end of the procedure was also observed in these patients (3 patients in the successful ablation group vs. 8 patients in the unsuccessful ablation group; p = 0.056). In multivariate regression analysis, paroxysmal AF was the only independent predictor of a successful outcome.
Catheter ablation of AF in patients with HCM is an effective and safe therapeutic option, particularly in patients with paroxysmal AF. Effectiveness of ablation is significantly smaller in patients with persistent AF and even more so in those with long-persistent AF. Repeated procedures were often necessary. Continued antiarrhythmic drug therapy is often required due to a significant degree of atrial remodelling.
Kardiologia polska 01/2013; 71(1):17-24. · 0.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A particularly dangerous condition in pregnant women is already dilated left ventricle with severe functional impairment. Taking as an example the case of woman with dilated cardiomyopathy (DCM) first diagnosed in 17th week of pregnancy, the paper discusses diagnostic, therapeutic challenges and management of heart failure during pregnancy. Repeat measurements of brain natiuretic peptide levels should be helpful in diagnosing heart failure. To distinguish DCM from peripartum cardiomyopathy the time of manifestation should be considered. The risk of serious events is associated with NYHA class and impairment of left ventricular ejection fraction. Angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin-II receptor blockers are contraindicated in pregnancy because of fetal toxicity. The incidence of sight effects is associated with time of administration of ACE-I and duration of treatment. Possible sight effects of drugs in fetus should be monitored (mainly ultrasonographically). ICD can be implanted during pregnancy if indicated. To assess the time and mode of delivery, a multidisciplinary team of different specialists is required. Subsequent pregnancy is contraindicated in a patient with DCM and low ejection fraction of left ventricle.
Medical science monitor: international medical journal of experimental and clinical research 06/2012; 18(6):CQ9-13. · 1.22 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Therapeutic management in pregnant patients with heart failure still remains a challenge, even though in most pregnant women with cardiac diseases an outcome is good. A 32-year-old woman, 17 weeks pregnant, was admitted to hospital with heart failure (HF) NYHA class III/IV. Echocardiography revealed enlarged LV, LVEF 13%, significant mitral insufficiency and pulmonary hypertension. The patient wished to continue the pregnancy. In a life-threatening condition, metoprolol, enalapril, spironolactone (for 5 days), furosemide, and digitalis were administered. Enalapril was continued for 42 days. Then the patient was switched to a dihydralazine and isosorbide mononitrate regimen. The fetus was controlled ultrasonographically. In the 19th week of pregnancy, the patient's condition improved (NYHA class II, LVEF 23%). The patient experienced 2 more episodes of HF exacerbation. In the 26th week of pregnancy, in a primary prevention of sudden cardiac death and because of 2nd-degree AV block, an ICD was implanted. In the 32nd week of pregnancy a cesarean section was performed. A male infant was delivered. The patient made a good recovery and was discharged on the 7th postoperative day. The newborn was discharged after 4 weeks, in good general condition. At 1-year follow-up the patient presented NYHA class II.
Medical science monitor: international medical journal of experimental and clinical research 04/2012; 18(5):CQ5-7. · 1.22 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Published data concerning risk factors of VF in WPW patients are inconsistent or contradictory. METHODS AND RESULTS: We included 1007 patient (pts) (mean age 35years; 45% female) with an accessory pathway (AP) referred for non pharmacological treatment. Group 1 consisted of 56 pts (42M, aged 34±15yrs) with an AP and documented VF and Group 2-951 pts (513M, aged 35±15yrs) with an AP and without VF. Univariate predictors of VF were: overt pre-excitation, male gender, multiple AP, large AP. Multivariate predictors were: overt pre-excitation, male gender and MAP. The mean shortest pre-excited RR interval during AF was significantly shorter in Group 1: 205±27 vs. 243±64, P=0.019. VF as an end point of the first arrhythmia episode (AVRT or AF) was observed in 20 pts (15M, 5F). Primary VF (no documented arrhythmia prior to aborted SCD) occurred in 16 pts (13M, 3F). The mean age of primary VF pts was significantly lower than of pts with history of AVRT or AVRT and/or AF (24.5 vs. 36.5 vs. 38yrs., P<0.005 and P=0.002, respectively). Age at VF occurrence shows a bi-modal distribution with peak occurrences in the 2-nd/3-rd and 5-th decades. CONCLUSION: In patients with an accessory pathway, overt pre-excitation, male gender and multiple AP constitute independent risk factors of VF episodes. Young patients in the 2-nd/3-rd and older patients in the 5-th decade might be at higher risk of VF occurrence.
International journal of cardiology 02/2012; · 6.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Effectiveness of implantable cardioverter-defibrillators (ICD) in patients with reduced left ventricular ejection fraction after myocardial infarction has been documented in large randomised trials. We analysed the predictive value of clinical factors at the time of implantation for adequate ICD interventions and mortality risk.
We analysed 121 consecutive patients (15 women, 106 [88%] men; mean age 62 ± 10 years) with coronary artery disease in whom ICD was implanted for primary prevention between 2001 and 2007. Mean duration of follow-up was 876 ± 538 days.
Forty-four (36.4%) patients had adequate ICD interventions. In the Cox analysis, wider QRS complexes (hazard ration [HR] per each 10 ms increment: 1.13, confidence interval [CI] 1.039-1.229, p = 0.0045) and younger age at the time of ICD implantation (HR per each 10 year increment: 0.7, CI 0.5-0.9, p = 0.0081) were associated with a higher probability of adequate intervention. Wider QRS complexes were associated with a higher probability of electrical storm (HR 1.059, CI 1.014-1.045, p = 0.0002). During follow-up, 21 (17.4%) patients died. In the Cox analysis, wider QRS complexes (HR per each 10 ms increment: 1.123, CI 1.011-1.248, p = 0.0306 [in univariate analysis only]), older age at the time of implantation (HR per each 10 year increment: 1.7, CI 1.1-2.8, p = 0.0396) and higher NYHA class (HR 4.4, CI 1.7-11.5, p = 0.0022) were associated with increased mortality. Mortality was reduced by previous revascularisation (HR 0.3, CI 0.1-0.7, p = 0.006).
Patients with wider QRS complexes at the time of ICD implantation had a higher probability of adequate device intervention and mortality risk. QRS complex widening was also associated with a higher incidence of electrical storm.
Kardiologia polska 01/2012; 70(4):360-8. · 0.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To assess the value of dyssynchrony and myocardial viability assessment by cardiac magnetic resonance (CMR) in prediction of response to cardiac resynchronization therapy (CRT) in patients with heart failure (HF) of both ischaemic and non-ischaemic etiologies.
Patients scheduled for CRT in NYHA class II-IV, left ventricular ejection fraction <35%, QRS ≥ 120 ms were included. Tagged cine and late gadolinium enhancement (LGE) images were performed. Dyssynchrony was assessed with inTag toolbox and LGE was quantified using cutoff value at half of maximal signal in the scar. Cardiopulmonary exercise test, echocardiography and blood testing for NT-proBNP levels were done at baseline and 6 months after CRT.
52 patients (age 60.3 ± 13 years) were included. 26 patients (50%) met response criteria. The ischaemic etiology of HF was more frequent (69% vs. 31%, p=0.002), the percent of LGE was higher (7.7% [0-13.5%] vs. 19.0% (0-31.9%], p=0.013), regional vector of circumferential strain variance (RVV) was lower (0.27 ± 0.08 vs. 0.34 ± 0.09, p=0.009) and uniformity of radial strain was higher (0.72 ± 0.25 vs. 0.56 ± 0.29, p=0.046) in non-responders vs. responders. Multivariate logistic regression showed that RVV predicted response to CRT (HR 2.3, 95% CI 1.02-5.02, p=0.0430) independently of LGE and the etiology of heart failure. In the subgroup of patients with ischaemic HF the extend of transmural scar within myocardium was higher in non-responders vs. responders (26.3% vs. 15.0% respectively, p=0.01) and was a predictor of response to CRT in univariable analysis (HR 0.87, 95% CI 0.77-0.98, p=0.025) providing the sensitivity of 76% and specificity of 75% at the cutoff point of 18% in the prediction of poor response to CRT. In patients with non-ischaemic HF QRS was wider (162 ms vs. 140 ms, p=0.04), regional vector of strain variance (RVV) was higher (0.39 vs. 0.25, p=0.002) and uniformity of radial strain was lower (0.52 vs. 0.80, p=0.049) in non-responders vs. responders. Univariable logistic regression showed that RVV was a predictor of response to CRT (HR 1.50, 95% CI 1.06-2.13, p=0.022), providing the sensitivity of 94% and specificity of 85% at the cutoff point of 0.31.
CMR derived parameters of dyssynchrony such as RVV may provide an additive value in prediction of response to CRT, especially in patients with non-ischaemic etiology of heart failure. In patients with ischaemic HF the transmurality of LGE is an important predictor of lack of response to CRT.
European journal of radiology 11/2011; 81(10):2639-47. · 2.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A patient with an implantable cardioverter-defibrillator (ICD) may suffer from neuromuscular disorders and may need to undergo a nerve conduction study (NCS). However, a NCS may be a source of electromagnetic interference (EMI). The aim of the present study was to investigate whether the interference from NCS used in a standardised test protocol affects ICD function.
Twenty patients (19 males; mean age of 59.8±9.9 years) with implantable ICDs (eight with integrated and 12 with true bipolar leads), treated with amiodarone and with symptoms suggesting neuropathy were included. NCS were conducted using repetitive stimulation with frequency of 2 Hz and single, rectangular pulses of intensity up to 100 mA. Stimulation was performed in standard sites including proximal sites in the arm.
The impulses generated NCS were not detected by the ICD, irrespective of the site, rate or stimulus intensity.
Standardised test protocol for an NCS is safe in patients with an ICD regardless of the leads type.
Current guidelines which limitate the NCS in patients with ICD may be the subject of revision.
Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology 06/2011; 123(1):211-3. · 3.12 Impact Factor