Effect of cardiac resynchronization therapy with implantable cardioverter defibrillator versus cardiac resynchronization therapy with pacemaker on mortality in heart failure patients: results of a high‐volume, single‐centre experience

Abstract

AimsThere are limited and contradictory data on the effects of CRT with implantable cardioverter defibrillator (CRT-D) on mortality as compared with CRT with pacemaker (CRT-P).Methods and resultsWe evaluated the long-term outcome of patients implanted with a CRT-D or CRT-P device in our high-volume single-centre experience. Data on all-cause mortality were derived from clinic visits and the Hungarian National Healthcare Fund Death Registry. Kaplan–Meier survival analyses and multivariate Cox regression models were used to evaluate all-cause mortality in patients with CRT-D vs. CRT-P, stratified by the aetiology of cardiomyopathy. From 2000 to 2011, 1122 CRT devices, 693 CRT-P (LVEF 28.2 ± 7.4%) and 429 CRT-D (LVEF 27.6 ± 6.4%), were implanted at our centre. During the median follow-up of 28 months, 379 patients died from any cause, 250 patients (36%) with an implanted CRT-P and 129 patients (30%) with an implanted CRT-D. There was no evidence of mortality benefit in patients implanted with a CRT-D compared with a CRT-P in the total cohort [hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.73–1.32, P = 0.884]. In patients with ischaemic cardiomyopathy, CRT-D treatment was associated with a significant 30% risk reduction in all-cause mortality compared with an implanted CRT-P (HR 0.70, 95% CI 0.51–0.97, P = 0.03). In non-ischaemic patients, there was no mortality benefit of CRT-D over CRT-P (HR 0.98, 95% CI 0.73–1.32, P = 0.894, interaction P-value = 0.15).ConclusionsIn heart failure patients with ischaemic cardiomyopathy, CRT-D was associated with a mortality benefit compared with CRT-P, but no benefit of CRT-D over CRT-P in mortality was observed in non-ischaemic cardiomyopathy.

Importance of Implantable Cardioverter‐Defibrillator Back‐Up in Cardiac Resynchronization Therapy Recipients: A Systematic Review and Meta‐Analysis

“…The number needed to treat (NNT) was 10. Ten studies showed significantly lower mortality rates with the CRT‐D device, while the remaining 9 were neutral . The observed I 2 values showed moderate heterogeneity within this analysis (I 2 =48%).…”

“…Patients with indication for CRT typically also fulfill the Sudden Cardiac Death in Heart Failure Trial (SCD‐HeFT) inclusion criteria and are therefore candidates for an ICD. Although, we would expect CRT‐Ds to be advantageous because SCD is frequently a cause of death in patients with heart failure, data from randomized controlled trials, observational studies, and registries have not provided a clear support towards the advantage of CRT‐Ds over CRT‐Ps in that setting . Among other possible issues, lack of statistical power may be one of the possible causes of this uncertain benefit.…”

“…An adequately powered randomized controlled trial on CRT‐D versus CRT‐P is very unlikely to be performed in the near future and therefore a meta‐analysis is the most adequate method to address this subject. The meta‐analysis by Jiang et al provided valuable insight, but several studies comparing CRT‐D with CRT‐P have been published since its publication …”

Gender-specific outcomes of cardiac resynchronisation therapy with or without defibrillator

“…Aetiology of cardiomyopathy might be a relevant confounder and effect modifier in this analysis. Previous report suggested benefit of CRT-D over CRT-P in patients with ischaemic cardiomyopathy, but not in patients with non-ischaemic cardiomyopathy 6. It has been well described that female patients implanted with CRT devices more often present with non-ischaemic cardiomyopathy and derive greater improvement in echo outcomes and clinical outcomes than patients with ischaemic cardiomyopathy 7.…”

Heartbeat: Cardiac resynchronization therapy with or without defibrillation: are women different?

“…In the accompanying editorial,2 Kutyifa notes that women accounted for only 15% of the CRT-D group but 42% of the CRT-P group, suggesting that sex may have affected the choice of CRT-P versus CRT-D and may have (perhaps inappropriately) influenced whether women received a CRT device at all. She also points out that under-representation of women, despite the attempt to correct for selection bias with propensity score analysis, limits the clinical applicability of this data until validated in other populations or, ideally, studied in a randomised controlled clinical trial.…”