Assessment of ICD eligibility in non-ischaemic cardiomyopathy patients: a position statement by the Task Force of the Dutch Society of Cardiology.

International guidelines recommend implantation of an implantable cardioverter-defibrillator (ICD) in non-ischaemic cardiomyopathy (NICM) patients with a left ventricular ejection fraction (LVEF) below 35% despite optimal medical therapy and a life expectancy of more than 1 year with good functional status. We propose refinement of these recommendations in patients with NICM, with careful consideration of additional risk parameters for both arrhythmic and non-arrhythmic death. These additional parameters include late gadolinium enhancement on cardiac magnetic resonance imaging and genetic testing for high-risk genetic variants to further assess arrhythmic risk, and age, comorbidities and sex for assessment of non-arrhythmic mortality risk. Moreover, several risk modifiers should be taken into account, such as concomitant arrhythmias that may affect LVEF (atrial fibrillation, premature ventricular beats) and resynchronisation therapy. Even though currently no valid cut-off values have been established, the proposed approach provides a more careful consideration of risks that may result in withholding ICD implantation in patients with low arrhythmic risk and substantial non-arrhythmic mortality risk.

NL-EVDR: Netherlands-ExtraVascular Device Registry.

Cardiac implantable electronic device (CIED) therapy is an essential element in treating cardiac arrhythmias. Despite their benefits, conventional transvenous CIEDs are associated with a significant risk of mainly pocket- and lead-related complications. To overcome these complications, extravascular devices (EVDs), such as the subcutaneous implantable cardioverter-defibrillator and intracardiac leadless pacemaker, have been developed. In the near future, several other innovative EVDs will become available. However, it is difficult to evaluate EVDs in large studies because of high costs, lack of long-term follow-up, imprecise data or selected patient populations. To improve evaluation of these technologies, real-world, large-scale, long-term data are of utmost importance. A Dutch registry-based study seems to be a unique possibility for this goal due to early involvement of Dutch hospitals in novel CIEDs and an existing quality control infrastructure, the Netherlands Heart Registration (NHR). Therefore, we will soon start the Netherlands-ExtraVascular Device Registry (NL-EVDR), a Dutch nationwide registry with long-term follow-up of EVDs. The NL-EVDR will be incorporated in NHR's device registry. Additional EVD-specific variables will be collected both retrospectively and prospectively. Hence, combining Dutch EVD data will provide highly relevant information on safety and efficacy. As a first step, a pilot project has started in selected centres in October 2022 to optimise data collection.

Development and external validation of prediction models to predict implantable cardioverter-defibrillator efficacy in primary prevention of sudden cardiac death.

AIMS: This study was performed to develop and externally validate prediction models for appropriate implantable cardioverter-defibrillator (ICD) shock and mortality to identify subgroups with insufficient benefit from ICD implantation. METHODS AND RESULTS: We recruited patients scheduled for primary prevention ICD implantation and reduced left ventricular function. Bootstrapping-based Cox proportional hazards and Fine and Gray competing risk models with likely candidate predictors were developed for all-cause mortality and appropriate ICD shock, respectively. Between 2014 and 2018, we included 1441 consecutive patients in the development and 1450 patients in the validation cohort. During a median follow-up of 2.4 (IQR 2.1-2.8) years, 109 (7.6%) patients received appropriate ICD shock and 193 (13.4%) died in the development cohort. During a median follow-up of 2.7 (IQR 2.0-3.4) years, 105 (7.2%) received appropriate ICD shock and 223 (15.4%) died in the validation cohort. Selected predictors of appropriate ICD shock were gender, NSVT, ACE/ARB use, atrial fibrillation history, Aldosterone-antagonist use, Digoxin use, eGFR, (N)OAC use, and peripheral vascular disease. Selected predictors of all-cause mortality were age, diuretic use, sodium, NT-pro-BNP, and ACE/ARB use. C-statistic was 0.61 and 0.60 at respectively internal and external validation for appropriate ICD shock and 0.74 at both internal and external validation for mortality. CONCLUSION: Although this cohort study was specifically designed to develop prediction models, risk stratification still remains challenging and no large group with insufficient benefit of ICD implantation was found. However, the prediction models have some clinical utility as we present several scenarios where ICD implantation might be postponed.

Mechanical extraction of cardiac implantable electronic devices leads with long dwell time: Efficacy and safety of the step up approach.

The aim of this study was to evaluate the efficacy and safety of the stepwise mechanical transvenous lead extraction approach in a patient population with chronically implanted transvenous leads with a long dwell time. From January 2014 till December 2018, all lead extractions with lead dwell time ≥5 years performed at our tertiary centre were retrospectively analysed. A total of 173 leads, from 78 patients (median age 68 years; 81% male) with a median dwell time of 9 years (interquartile range [IQR] 5) were extracted, with three or more leads in 42% of the patients. Right atrial leads: 41%; right ventricular pacing leads: 16%; implantable cardioverter-defibrillator (ICD) leads: 31% (72% dual coil); coronary sinus leads: 12%. The majority (75%) of the leads had an active fixation. Most frequent indication for extraction was pocket infection/erosion (76%). Overall clinical success was 97%, and complete procedural success was 93%. Venous patency, assessed with venous angiography, was well preserved in 93% of the cases. The overall procedural complication rate was 3.8% (2.6% major and 1.3% minor). Despite the complexity of the population and a very long dwell time (median 9 years), a clinical success rate of 97% was achieved with the stepwise mechanical approach. Analysis of impeding progression of pectoral extraction suggests that dense fibrosis and sharp lead curvature in the transvenous trajectory pose a challenge. Complication rate was low, and acute venous patency was generally well preserved.

Prophylactic Use of Implantable Cardioverter-Defibrillators in the Prevention of Sudden Cardiac Death in Dialysis Patients.

BACKGROUND: Patients with end-stage renal disease who are undergoing dialysis are reported to be at high risk of sudden cardiac death (SCD), and to date, no therapy has been shown to be effective in reducing this risk. The feasibility and value of prophylactic implantable cardioverter-defibrillator (ICD) implantation to prevent SCD is uncertain. METHODS: We conducted the ICD2 trial (Implantable Cardioverter-Defibrillator in Dialysis Patients), a prospective, randomized, controlled study investigating the value and safety of ICD implantation to prevent SCD in 200 patients on dialysis with a left ventricular ejection fraction ≥35%, after adequate screening and optimization of other treatments. The primary end point was SCD. Secondary end points were all-cause mortality and ICD-related complications. RESULTS: The trial was stopped as per the recommendation of the data and safety monitoring board for futility reasons after inclusion of 188 patients, 97 in the ICD group and 91 in the control group. The median duration of follow-up was 6.8 years (interquartile range, 3.8-8.8 years). SCD occurred in 19 of 188 cases (10.1%), 11 of 97 in the ICD group and 8 of 91 in the control group. The cumulative SCD incidence at 5 years was 9.7% (95% CI, 3.3%-16.2%) in the ICD group and 7.9% (95% CI, 1.7-14.0%) in the control group, resulting in a hazard ratio of 1.32 (95% CI, 0.53-3.29; P=0.55). Overall, 99 of 188 patients died (52.7%), 52 in the ICD group and 47 in the control group. Five-year survival probability was 50.6% (95% CI, 39.8%-61.5%) in the ICD group and 54.5% (95% CI, 43.0-66.0%) in the control group, resulting in a hazard ratio of 1.02 (95% CI, 0.69-1.52; P=0.92). Among 80 patients who received an ICD, 25 adverse events related to ICD implantation occurred. CONCLUSIONS: In a well-screened and well-treated population undergoing dialysis, prophylactic ICD therapy did not reduce the rate of SCD or all-cause mortality, which remained high. CLINICAL TRIAL REGISTRATION: URL: http://www.controlled-trials.com . Unique identifier: ISRCTN20479861.

Cardiac resynchronization therapy in adults with congenital heart disease.

Aims: In adults with congenital heart disease (CHD) heart failure is one of the leading causes of morbidity and mortality but experience with and reported outcome of cardiac resynchronization therapy (CRT) is limited. We investigated the efficacy of CRT in adults with CHD. Methods and results: This was a retrospective study including 48 adults with CHD who received CRT since 2003 in four tertiary referral centres. Responders were defined as patients who showed improvement in NYHA functional class and/or systemic ventricular ejection fraction by at least one category. Ventricular function was assessed by echocardiography and graded on a four point ordinal scale. Median age at CRT was 47 years (range 18-74 years) and 77% was male. Cardiac diagnosis included tetralogy of Fallot in 29%, (congenitally corrected) transposition of great arteries in 23%, septal defects in 25%, left sided lesions in 21%, and Marfan syndrome in 2% of the patients. The median follow-up duration after CRT was 2.6 years (range 0.1-8.8). Overall, 37 out of 48 patients (77%) responded to CRT either by improvement of NYHA functional class and/or systemic ventricular function. There were 11 non-responders to CRT. Of these, three patients died and four underwent heart transplantation. Conclusion: In this cohort of older CHD patients, CRT was accomplished with a success rate comparable to those with acquired heart disease despite the complex anatomy and technical challenges frequently encountered in this population. Further studies are needed to establish appropriate guidelines for patient selection and long term outcome.

Application and comparison of the FADES, MADIT, and SHFM-D risk models for risk stratification of prophylactic implantable cardioverter-defibrillator treatment.

AIMS: Implantable cardioverter-defibrillator (ICD) treatment is beneficial in selected patients. However, it remains difficult to accurately predict which patients benefit most from ICD implantation. For this purpose, different risk models have been developed. The aim was to validate and compare the FADES, MADIT, and SHFM-D models. METHODS AND RESULTS: All patients receiving a prophylactic ICD at the Leiden University Medical Center were evaluated. Individual model performance was evaluated by C-statistics. Model performances were compared using net reclassification improvement (NRI) and integrated differentiation improvement (IDI). The primary endpoint was non-benefit of ICD treatment, defined as mortality without prior ventricular arrhythmias requiring ICD intervention. A total of 1969 patients were included (age 63 ± 11 years; 79% male). During a median follow-up of 4.5 ± 3.9 years, 318 (16%) patients died without prior ICD intervention. All three risk models were predictive for event-free mortality (all: P < 0.001). The C-statistics were 0.66, 0.69, and 0.75, respectively, for FADES, MADIT, and SHFM-D (all: P < 0.001). Application of the SHFM-D resulted in an improved IDI of 4% and NRI of 26% compared with MADIT; IDI improved 11% with the use of SHFM-D instead of FADES (all: P < 0.001), but NRI remained unchanged (P = 0.71). Patients in the highest-risk category of the MADIT and SHFM-D models had 1.7 times higher risk to experience ICD non-benefit than receive appropriate ICD interventions [MADIT: mean difference (MD) 20% (95% CI: 7-33%), P = 0.001; SHFM-D: MD 16% (95% CI: 5-27%), P = 0.005]. Patients in the highest-risk category of FADES were as likely to experience ICD intervention as ICD non-benefit [MD 3% (95% CI: -8 to 14%), P = 0.60]. CONCLUSION: The predictive and discriminatory value of SHFM-D to predict non-benefit of ICD treatment is superior to FADES and MADIT in patients receiving prophylactic ICD treatment.

Prognostic Impact of Implementation of QRS Characteristics in the Seattle Heart Failure Model in ICD and CRT-D Recipients.

BACKGROUND: The Seattle Heart Failure Model (SHFM) provides accurate estimates of survival in heart failure (HF) patients. The model is, however, not developed for HF patients with cardiac resynchronization therapy (CRT). The aim of this study was to assess the prognostic value of SHFM combined with QRS morphology and CRT-related change in QRS duration in implantable cardioverter defibrillator (ICD) and CRT defibrillator (CRT-D) recipients. METHODS: All patients who underwent prophylactic ICD implantation at the Leiden University Medical Center since 1996 were included. Baseline SHFM, QRS morphology, and duration before and after device implantation were determined. The regression coefficients of the QRS characteristics derived from a Cox regression analysis were implemented in the SHFM. SHFM-estimated survival was compared with Kaplan-Meier observed survival. RESULTS: The current study includes 1,834 defibrillator recipients (63 ± 11 years; 79% male; 53% CRT-D). In 585 (60%) CRT-D recipients a left bundle branch block was present, the mean QRS duration was 147 ± 31 ms before and 151 ± 27 ms after device implantation. After a median follow-up of 4.4 years (25(th) -75(th) percentile 2.7-6.4 years), 285 (29%) CRT-D recipients had died. CRT-related decrease in QRS duration adjusted for QRS morphology was associated with improved survival (hazard ratio 1.05/10 ms; 95% confidence interval [CI]: 1.01-1.09; P = 0.02). The estimated 5-year survival of CRT-D recipients after implementation of the QRS characteristic was 70%, and comparable with the observed 5-year survival of 68% (95% CI: 65-72). CONCLUSION: Implementation of native QRS morphology and change in QRS duration due to CRT in the SHFM improves the prognostic value of this model in HF patients with CRT-D.

EuroEco (European Health Economic Trial on Home Monitoring in ICD Patients): a provider perspective in five European countries on costs and net financial impact of follow-up with or without remote monitoring.

AIM: Remote follow-up (FU) of implantable cardiac defibrillators (ICDs) allows for fewer in-office visits in combination with earlier detection of relevant findings. Its implementation requires investment and reorganization of care. Providers (physicians or hospitals) are unsure about the financial impact. The primary end-point of this randomized prospective multicentre health economic trial was the total FU-related cost for providers, comparing Home Monitoring facilitated FU (HM ON) to regular in-office FU (HM OFF) during the first 2 years after ICD implantation. Also the net financial impact on providers (taking national reimbursement into account) and costs from a healthcare payer perspective were evaluated. METHODS AND RESULTS: A total of 312 patients with VVI- or DDD-ICD implants from 17 centres in six EU countries were randomised to HM ON or OFF, of which 303 were eligible for data analysis. For all contacts (in-office, calendar- or alert-triggered web-based review, discussions, calls) time-expenditure was tracked. Country-specific cost parameters were used to convert resource use into monetary values. Remote FU equipment itself was not included in the cost calculations. Given only two patients from Finland (one in each group) a monetary valuation analysis was not performed for Finland. Average age was 62.4 ± 13.1 years, 81% were male, 39% received a DDD system, and 51% had a prophylactic ICD. Resource use with HM ON was clearly different: less FU visits (3.79 ± 1.67 vs. 5.53 ± 2.32; P < 0.001) despite a small increase of unscheduled visits (0.95 ± 1.50 vs. 0.62 ± 1.25; P < 0.005), more non-office-based contacts (1.95 ± 3.29 vs. 1.01 ± 2.64; P < 0.001), more Internet sessions (11.02 ± 15.28 vs. 0.06 ± 0.31; P < 0.001) and more in-clinic discussions (1.84 ± 4.20 vs. 1.28 ± 2.92; P < 0.03), but with numerically fewer hospitalizations (0.67 ± 1.18 vs. 0.85 ± 1.43, P = 0.23) and shorter length-of-stay (6.31 ± 15.5 vs. 8.26 ± 18.6; P = 0.27), although not significant. For the whole study population, the total FU cost for providers was not different for HM ON vs. OFF [mean (95% CI): €204 (169-238) vs. €213 (182-243); range for difference (€-36 to 54), NS]. From a payer perspective, FU-related costs were similar while the total cost per patient (including other physician visits, examinations, and hospitalizations) was numerically (but not significantly) lower. There was no difference in the net financial impact on providers [profit of €408 (327-489) vs. €400 (345-455); range for difference (€-104 to 88), NS], but there was heterogeneity among countries, with less profit for providers in the absence of specific remote FU reimbursement (Belgium, Spain, and the Netherlands) and maintained or increased profit in cases where such reimbursement exists (Germany and UK). Quality of life (SF-36) was not different. CONCLUSION: For all the patients as a whole, FU-related costs for providers are not different for remote FU vs. purely in-office FU, despite reorganized care. However, disparity in the impact on provider budget among different countries illustrates the need for proper reimbursement to ensure effective remote FU implementation.

How adequate are the current methods of lead extraction? A review of the efficiency and safety of transvenous lead extraction methods.

Currently several extraction tools are available in order to allow safe and successful transvenous lead extraction (TLE) of pacemaker and ICD leads; however, no directives exist to guide physicians in their choice of extraction tools and approaches. To aim of the current review is to provide an overview of the success and complication rates of different extraction methods and tools available. A comprehensive search of all published literature was conducted in the databases of PubMed, Embase, Web of Science, and Central. Included papers were original articles describing a specific method of TLE and the corresponding success rates of at least 50 patients. Fifty-three studies were included; the majority (56%) utilized 2 (1-4) different venous extraction approaches (subclavian and femoral), the median number of extraction tools used was 3 (1-6). A stepwise approach was utilized in the majority of the studies, starting with simple traction which resulted in successful TLE in 7-85% of the leads. When applicable the procedure was continued with non-powered tools resulting in a successful extraction of 34-87% leads. Subsequently, powered tools were applied whereby success rates further increased to 74-100%. The final step in TLE was usually utilized by femoral snare leading to an overall TLE success rate of 96-100%. The median procedure-related mortality and major complication described were, respectively, 0% (0-3%) and 1% (0-7%) per patient. In conclusion, a stepwise extraction approach can result in a clinical successful TLE in up to 100% of the leads with a relatively low risk of procedure-related mortality and complications.

Chronic kidney disease and implantable cardioverter defibrillator related complications: 16 years of experience.

INTRODUCTION: Implantable cardioverter defibrillator (ICD) implantation has become an accepted therapy for the prevention of sudden cardiac death. However, serious comorbidities such as chronic kidney disease (CKD) are influencing the beneficial effects of ICD therapy. In this study, the association between kidney function and the occurrence of ICD related complications was assessed. METHODS: All patients receiving an ICD or cardiac resynchronization therapy-defibrillator between 1996 and 2012 were included. Renal function was categorized as: glomerular filtration rate (GFR) >90, GFR 30-90 or GFR <30 mL/min/1.73 m(2) . Registered complications were pocket hematoma, pneumothorax, lead complications, and device infection. RESULTS: In 3,147 device recipients, 236 patients (7.5%) suffered from at least 1 complication. Patients with a GFR <30 (n = 110) had a higher event rate for hematoma, pneumothorax, and infection. These patients were older, had a higher incidence of hypertension, diabetes, and a lower body mass index (BMI; P < 0.05). After correcting for these risk factors, hematoma remained independently associated with a GFR <30 mL/min (OR 2.7, CI: 1.05-6.9, P = 0.04). Device infection, pneumothorax, and lead complications were not independently associated with a GFR <30 mL/min/1.73 m(2) . CONCLUSIONS: Patients with CKD suffered from more ICD related complications than patients without kidney disease. This was partially associated with kidney dysfunction itself as was the case with the occurrence of hematoma. However, the high burden of risk factors associated with device complications in patients with renal disease played an important role as well.

Feasibility, safety, and short-term outcome of leadless ultrasound-based endocardial left ventricular resynchronization in heart failure patients: results of the wireless stimulation endocardially for CRT (WiSE-CRT) study.

AIMS: Left ventricular (LV) endocardial pacing may address the limitations in the selection of an LV pacing site and provide improvements in cardiac resynchronization therapy (CRT) effectiveness. We report on the feasibility, the safety, and the short-term outcome of a leadless ultrasound-based technology for LV endocardial resynchronization in heart failure (HF) patients enroled into the Wireless Stimulation Endocardially for CRT (WiSE-CRT) study. METHODS AND RESULTS: Seventeen HF patients were enroled and categorized as: (i) patients in whom attempted coronary sinus lead implantation for CRT had failed (n = 7); (ii) patients with a previously implanted CRT device, not responding to CRT (n = 2); and (iii) patients with previously implanted pacemakers or implantable cardioverter-defibrillator and meeting the standard indications for CRT (n = 8). System implantation was achieved in 13 patients (76.5%); mean R-wave amplitude was 5.6 ± 3.2 mV and the mean pacing threshold was 1.6 ± 1.0 V, respectively. In one patient, no sufficient pacing thresholds were found; in three patients pericardial effusion occurred. Biventricular pacing was recorded in 83% and 92% of the patients at 1 month and 6 months, respectively. QRS duration was shorter during biventricular pacing compared with right ventricular pacing at 1 month (-41 ms; P = 0.0002) and 6 months (-42 ms; P = 0.0011), respectively. At the 6-month follow-up, two-thirds of the patients had at least one functional class change. Left ventricular ejection fraction significantly increased (P < 0.01) by 6 points at the 6-month follow-up. CONCLUSION: The feasibility of providing an endocardial stimulation for CRT with a leadless technology was successfully demonstrated. Despite the promising results for a novel technology, further study is required to definitively conclude the safety and the performance of the system. CLINICAL TRIAL REGISTRATION INFORMATION: NCT01294527.

Cost-effectiveness of primary prevention implantable cardioverter defibrillator treatment: data from a large clinical registry.

BACKGROUND: Although randomized trials have shown the beneficial effect on survival of an implantable cardioverter defibrillator (ICD) as primary prevention therapy in selected patients, data concerning the cost-effectiveness in routine clinical practice remain scarce. Accordingly, the purpose of this study was to assess the cost-effectiveness of primary prevention ICD implantation in the real world. METHODS: Patients receiving primary prevention single-chamber or dual-chamber ICD implantation at the Leiden University Medical Center were included in the study. Using a Markov model, lifetime cost, life years (LYs), and gained quality-adjusted life years (QALYs) were estimated for device recipients and control patients. Data on mortality, complication rates, and device longevity were retrieved from our center and entered into the Markov model. To account for model assumptions, one-way deterministic and probabilistic sensitivity analyses were performed. Importantly, calculations for the estimated incremental cost-effectiveness rate (ICER) per QALY gained are based on several numbers of assumptions, and accordingly findings may have over- or underestimated the cost-effectiveness of ICD therapy. RESULTS: Primary prevention ICD implantation adds an estimated mean of 2.07 LYs and 1.73 QALYs. Increased lifetime cost for single-chamber and dual-chamber ICD recipients were estimated at €60,788 and €64,216, respectively. This resulted for single-chamber ICD recipients, in an estimated ICER of €35,154 per QALY gained. In dual-chamber ICD recipients, an estimated ICER of €37,111 per QALY gained was calculated. According to the probabilistic sensitivity analysis, estimated cost per QALY gained are €35,837 (95% confidence interval [CI]: €28,368-€44,460) for single-chamber and €37,756 (95% CI: €29,055-€46,050) for dual-chamber ICDs. CONCLUSIONS: On the basis of data and detailed costs, derived from routine clinical practice, ICD therapy in selected patients with a reduced left ventricular ejection fraction appears to be cost-effective.

Atrial-based pacing has no benefit over ventricular pacing in preventing atrial arrhythmias in adults with congenital heart disease.

AIMS: To determine whether atrial-based pacing prevents atrial arrhythmias in adults with congenital heart disease (CHD) compared with ventricular pacing. METHODS AND RESULTS: All adult CHD patients from four participating centres with a permanent pacemaker were identified. Patients with permanent atrial arrhythmias at pacemaker implantation and patients who received a pacemaker for treatment of drug-refractory atrial arrhythmias were excluded. The final study population consisted of 211 patients (52% male, 36% complex CHD) who received a first pacemaker for sick sinus dysfunction (n = 82) or atrioventricular block (n = 129) at a median age of 24 years [interquartile range (IQR), 12-34]. A history of atrial arrhythmias at implantation was present in 49 patients (23%). Atrial-based pacing was the initial pacing mode in 139 patients (66%) while the others (34%) received ventricular pacing. During a median follow-up of 13 years (IQR, 7-21), 90 patients (43%) developed an atrial arrhythmia. Multivariate analysis demonstrated no significant effect of atrial-based pacing on subsequent atrial arrhythmias [hazard ratio (HR), 1.53; 95% confidence interval (CI), 0.91-2.56; P = 0.1]. Independent predictors of atrial arrhythmia were history of atrial arrhythmias (HR, 5.55; 95% CI, 3.47-8.89; P< 0.0001), older age (≥18 years) at pacemaker implantation (HR, 2.29; 95% CI, 1.29-4.04; P = 0.005), and complex CHD (HR, 1.57; 95% CI, 1.01-2.45; P = 0.04). CONCLUSION: In contrast to the general population, atrial-based pacing was not associated with a lower incidence of atrial arrhythmia in adults with CHD.

Predictors of long-term benefit of cardiac resynchronization therapy in patients with right bundle branch block.

AIMS: The aims of this study were: (i) to characterize consecutive cardiac resynchronization therapy (CRT) recipients with right bundle branch block (RBBB) in comparison with left bundle branch block (LBBB) and (ii) to identify independent predictors of long-term outcome among CRT recipients with RBBB. The presence of RBBB has been associated with poorer prognosis after CRT compared with LBBB; however, little is known about the differences in cardiac mechanics between RBBB and LBBB patients. Furthermore, predictors of favourable outcome after CRT in patients with RBBB have not been identified. METHODS AND RESULTS: Five hundred and sixty-one consecutive CRT recipients (89 with RBBB and 472 with LBBB) underwent echocardiography before and 6 months after CRT to determine left ventricular (LV) size and function, and interventricular and LV dyssynchrony (as measured by tissue Doppler imaging). Long-term follow-up to identify a composite endpoint of all-cause mortality or heart failure hospitalization was available. Right bundle branch block patients exhibited a higher prevalence of male gender, ischaemic heart disease, atrial fibrillation, and lower exercise capacity when compared with LBBB patients, despite smaller LV volumes. In addition, the extent of both interventricular and LV dyssynchrony was less in RBBB patients. Six months after CRT, RBBB patients also showed limited LV reverse remodelling. At long-term follow-up, LV dyssynchrony and mitral regurgitation were identified as independent predictors of all-cause mortality or heart failure hospitalization among RBBB patients. CONCLUSION: Left ventricular dyssynchrony may be an important determinant of outcome following CRT in patients with RBBB and may help in the selection of CRT candidates.

Effect of cardiac resynchronization therapy in patients without left intraventricular dyssynchrony.

AIMS: To evaluate the effects of cardiac resynchronization therapy (CRT) on long-term survival of patients without baseline left ventricular (LV) mechanical dyssynchrony. METHODS AND RESULTS: A total of 290 heart failure patients (age 67 ± 10 years, 77% males) without significant baseline LV dyssynchrony (<60 ms as assessed with tissue Doppler imaging) were treated with CRT. Patients were divided according to the median LV dyssynchrony measured after 48 h of CRT into two groups. All-cause mortality was compared between the subgroups. In addition, the all-cause mortality rates of these subgroups were compared with the all-cause mortality of 290 heart failure patients treated with CRT who showed significant LV dyssynchrony (≥60 ms) at baseline. In the group of patients without significant LV dyssynchrony, median LV dyssynchrony increased from 22 ms (inter-quartile range 16-34 ms) at baseline to 40 ms (24-56 ms) 48 h after CRT. The cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with LV dyssynchrony ≥40 ms 48 h after CRT implantation were significantly higher when compared with patients with LV dyssynchrony <40 ms (10, 17, and 23 vs. 3, 8, and 10%, respectively; log-rank P< 0.001). Finally, the cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with baseline LV dyssynchrony were 3, 8, and 11%, respectively (log-rank P= 0.375 vs. patients with LV dyssynchrony <40 ms). Induction of LV dyssynchrony after CRT was an independent predictor of mortality (hazard ratio: 1.247; P= 0.009). CONCLUSION: In patients without significant LV dyssynchrony, the induction of LV dyssynchrony after CRT may be related to a less favourable long-term outcome.

One-Year Mortality in Patients Undergoing an Implantable Cardioverter Defibrillator or Cardiac Resynchronization Therapy Pulse Generator Replacement: Identifying Patients at Risk.

Implantable cardioverter defibrillators (ICDs) significantly contribute to the prevention of sudden cardiac death in selected patients. However, it is essential to identify those who are likely to not have benefit from an ICD and to defer a pulse generator exchange. Easily implementable guidelines for individual risk stratification and decision making are lacking. This study investigates the 1-year mortality of patients who underwent an ICD or cardiac resynchronization therapy with defibrillator function (CRT-D) pulse generator replacement in a contemporary real-world tertiary hospital setting. The cause of death and patient- and procedure-related factors are stratified, and predictive values for 1-year mortality are evaluated. Patients with a follow-up of ≥365 days (or prior mortality) after an ICD or CRT-D exchange at the Leiden University Medical Center from 1 January 2018 until 31 December 2021 were eligible. In total, 588 patients were included (77% male, 69 [60-76] years old, 59% primary prevention, 46% ischemic cardiomyopathy and 37% mildly reduced left ventricular ejection fraction (LVEF)). Patients undergoing a CRT-D replacement or upgrade had a significantly higher 1-year all-cause mortality (10.7% and 11.9%, respectively) compared to patients undergoing ICD (2.8%) exchange (p = 0.002). LVEF ≤ 30%, New York Heart Association class ≥ 3, estimated glomerular filtration rate ≤ 30 mL/min/m2 and haemoglobin ≤ 7 mmol/L were independently associated with mortality within 1 year after pulse generator replacement. There is a growing need for prospectively validated risk scores to weight individualized risk of mortality with the expected ICD therapy benefit and to support a well-informed, shared decision-making process.

Five-year safety and efficacy of leadless pacemakers in a Dutch cohort.

BACKGROUND: Adequate real-world safety and efficacy of leadless pacemakers (LPs) have been demonstrated up to 3 years after implantation. Longer-term data are warranted to assess the net clinical benefit of leadless pacing. OBJECTIVE: The purpose of this study was to evaluate the long-term safety and efficacy of LP therapy in a real-world cohort. METHODS: In this retrospective cohort study, all consecutive patients with a first LP implantation from December 21, 2012, to December 13, 2016, in 6 Dutch high-volume centers were included. The primary safety endpoint was the rate of major procedure- or device-related complications (ie, requiring surgery) at 5-year follow-up. Analyses were performed with and without Nanostim battery advisory-related complications. The primary efficacy endpoint was the percentage of patients with a pacing capture threshold ≤2.0 V at implantation and without ≥1.5-V increase at the last follow-up visit. RESULTS: A total of 179 patients were included (mean age 79 ± 9 years), 93 (52%) with a Nanostim and 86 (48%) with a Micra VR LP. Mean follow-up duration was 44 ± 26 months. Forty-one major complications occurred, of which 7 were not advisory related. The 5-year major complication rate was 4% without advisory-related complications and 27% including advisory-related complications. No advisory-related major complications occurred a median 10 days (range 0-88 days) postimplantation. The pacing capture threshold was low in 163 of 167 patients (98%) and stable in 157 of 160 (98%). CONCLUSION: The long-term major complication rate without advisory-related complications was low with LPs. No complications occurred after the acute phase and no infections occurred, which may be a specific benefit of LPs. The performance was adequate with a stable pacing capture threshold.

Practices of cardiac implantable electronic device follow-up: results of the European Heart Rhythm Association survey.

This survey analyses some details of follow-up of patients with cardiac implantable electronic devices (CIEDs) in 40 centres-the members of the European Heart Rhythm Association (EHRA) research network. Results of this survey show that practices of CIED follow-up are not homogeneous between EHRA research network centres, and recommended clinical evaluation of the patients regarding possible device up-grade is not always performed. Remote device monitoring appears to be an evolving practice, mostly used in implantable cardioverter defibrillators and cardiac resynchronization therapy defibrillator recipients.

Trans-venous lead removal without the use of extraction sheaths, results of >250 removal procedures.

AIMS: The number of implanted cardiac rhythm devices has rapidly increased in the past decade. Subsequently, the need for lead extraction has also increased. Several techniques of lead removal have been documented from manual traction of the lead to lead extraction assisted with mechanical or laser sheaths. The goal of this study was to review our experience with lead removal using manual traction without the assistance of extraction sheaths. METHODS AND RESULTS: In the Leiden University Medical Center all leads are removed using manual traction without the assistance of extraction sheaths. We have retrospectively reviewed all lead removal procedures performed between 2000 and 2009. Procedures were reviewed for indication, success, complication rates, and mortality. In total, 279 lead removal procedures were included. During these procedures 445 leads were removed. Time since lead implantation: 4.2 ± 4.7 years. During extraction 53(11.9%) leads fractured, of which >50% could still be completely removed using a femoral approach. A longer implantation duration [odds ratio (OR) 1.16 per year, 95% confidence interval (CI) 1.09-1.23] and passive fixation (OR 2.52, 95%CI 1.17-5.45) significantly associated with the chance of lead fracture during lead removal. Clinical success, using the primary approach of manual traction from the pectoral area, was obtained in 228 (84.8%) procedures. Major complications occurred in 2(0.7%) and minor in 13(4.7%) procedures. One patient died within 24 h after the procedure due to septic shock. There was no further mortality within the first month after the procedure. CONCLUSION: Lead removal using manual traction, without the assistance of lead extraction sheaths, is clinically successful in ~85% of the lead extraction procedures. Concomitant morbidity and mortality are low. The highest clinical success (~95%) was observed in patients with leads implanted less than 2.6 years.