Causes-of-death analysis of patients with cardiac resynchronization therapy: an analysis of the CeRtiTuDe cohort study

Phenogrouping and risk stratification of patients undergoing cardiac resynchronization therapy upgrade using topological data analysis

Choosing the optimal device during cardiac resynchronization therapy (CRT) upgrade can be challenging. Therefore, we sought to provide a solution for identifying patients in whom upgrading to a CRT-defibrillator (CRT-D) is associated with better long-term survival than upgrading to a CRT-pacemaker (CRT-P). To this end, we first applied topological data analysis to create a patient similarity network using 16 clinical features of 326 patients without prior ventricular arrhythmias who underwent CRT upgrade. Then, in the generated circular network, we delineated three phenogroups exhibiting significant differences in clinical characteristics and risk of all-cause mortality. Importantly, only in the high-risk phenogroup was upgrading to a CRT-D associated with better survival than upgrading to a CRT-P (hazard ratio: 0.454 (0.228-0.907), p = 0.025). Finally, we assigned each patient to one of the three phenogroups based on their location in the network and used this labeled data to train multi-class classifiers to enable the risk stratification of new patients. During internal validation, an ensemble of 5 multi-layer perceptrons exhibited the best performance with a balanced accuracy of 0.898 (0.854-0.942) and a micro-averaged area under the receiver operating characteristic curve of 0.983 (0.980-0.986). To allow further validation, we made the proposed model publicly available ( https://github.com/tokmarton/crt-upgrade-risk-stratification ).

Arrhythmic and mortality outcomes in patients with dilated cardiomyopathy receiving cardiac resynchronization therapy without defibrillator

INTRODUCTION

The routine implantation of cardiac resynchronization therapy with defibrillators in all patients who are candidates for this treatment is now being negotiated, mainly in patients with dilated cardiomyopathy.

OBJECTIVE

We investigated the arrhythmic and mortality outcomes following CRT implantation in DCM, as well as the necessity for defibrillator capabilities in that particular group of patients.

METHODS

we included 67- patients with DCM with EF ≤ 35%, QRS duration >130 msec and NYHA class II-IV, or those with EF ≤ 35% with indications of permanent pacing for implantation of CRT-P. Patients were followed to obtain good CRT response. Improved clinical outcomes were defined as improvement in at least one NYHA class, ≥5% increase in LVEF, and ≥15% reduction in left ventricular end-systolic volume versus baseline. Patients were classified into responder and non-responder. Patients were followed for 36 months regarding all-cause morbidity mainly ventricular tachycardia and all-cause mortality.

RESULTS

CRT responder patients had better clinical outcomes than CRT non-responder patients (post NYHA, 1.3 ± 0.5 vs. 2.5 ± 0.6, p < 0.0001; post LVEF 30.0 ± 1.6 vs. 20.3 ± 2.2%, p < 0.0001; LVESV, 151.7 ± 7.6 vs. 190.4 ± 9.0 ml, p < 0.0001), with lower ventricular arrhythmia (p < 0.0001), lower mortality (p = 0.015) and lower all-cause morbidity (p < 0.001). This survival advantage may be related to the response to CRT response determined by clinical and echocardiographic parameters over a 36-month period of follow-up.

CONCLUSIONS

Our findings suggest that CRT-P implantation without defibrillation backup is an encouraging treatment option for patients with DCM, principally those who responded to it. It may result in cost savings, a decrease in complications, and an improvement in all-cause morbidity, particularly ventricular arrhythmia and survival.

Time-trend treatment effect of cardiac resynchronization therapy with or without defibrillator on mortality: a systematic review and meta-analysis

AIMS

This study aimed to investigate the impact of cardiac resynchronization therapy with a defibrillator (CRT-D) on mortality, comparing it with CRT with a pacemaker (CRT-P). Additionally, the study sought to identify subgroups, evaluate the time trend in treatment effects, and analyze patient characteristics, considering the changing indications over the past decades.

METHODS AND RESULTS

PubMed, CENTRAL, and Embase up to October 2021 were screened for studies comparing CRT-P and CRT-D, focusing on mortality. Altogether 26 observational studies were selected comprising 128 030 CRT patients, including 55 469 with CRT-P and 72 561 with CRT-D device. Cardiac resynchronization therapy with defibrillator was able to reduce all-cause mortality by almost 20% over CRT-P [adjusted hazard ratio (HR): 0.85; 95% confidence interval (CI): 0.76-0.94; P < 0.01] even in propensity-matched studies (HR: 0.83; 95% CI: 0.80-0.87; P < 0.001) but not in those with non-ischaemic aetiology (HR: 0.95; 95% CI: 0.79-1.15; P = 0.19) or over 75 years (HR: 1.08; 95% CI 0.96-1.21; P = 0.17). When treatment effect on mortality was investigated by the median year of inclusion, there was a difference between studies released before 2015 and those thereafter. Time-trend effects could be also observed in patients' characteristics: CRT-P candidates were getting older and the prevalence of ischaemic aetiology was increasing over time.

CONCLUSION

The results of this systematic review of observational studies, mostly retrospective with meta-analysis, suggest that patients with CRT-D had a lower risk of mortality compared with CRT-P. However, subgroups could be identified, where CRT-D was not superior such as non-ischaemic and older patients. An improved treatment effect of CRT-D on mortality could be observed between the early and late studies partly related to the changed characteristics of CRT candidates.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

The evolving state of cardiac resynchronization therapy and conduction system pacing: 25 years of research at EP Europace journal

Cardiac resynchronization therapy (CRT) was proposed in the 1990s as a new therapy for patients with heart failure and wide QRS with depressed left ventricular ejection fraction despite optimal medical treatment. This review is aimed first to describe the rationale and the physiologic effects of CRT. The journey of the landmark randomized trials leading to the adoption of CRT in the guidelines since 2005 is also reported showing the high level of evidence for CRT. Different alternative pacing modalities of CRT to conventional left ventricular pacing through the coronary sinus have been proposed to increase the response rate to CRT such as multisite pacing and endocardial pacing. A new emerging alternative technique to conventional biventricular pacing, conduction system pacing (CSP), is a promising therapy. The different modalities of CSP are described (Hirs pacing and left bundle branch area pacing). This new technique has to be evaluated in clinical randomized trials before implementation in the guidelines with a high level of evidence.

Effectiveness of adding a defibrillator with cardiac resynchronization therapy in heart failure according to the modified Model for End-stage Liver Disease-Albumin score

Current guidelines lack clear recommendations between the implantation of cardiac resynchronization therapy (CRT) with defibrillator (CRT-D) and CRT with pacemaker (CRT-P). We hypothesized that modified model for end-stage liver disease score including albumin (MELD-Albumin score), could be used to select patients who may not benefit from CRT-D. We consecutively included patients with CRT-P or CRT-D implantation between 2010 and 2022. The primary endpoint was the composite of all-cause mortality or worsening heart failure. We performed multivariable-adjusted Cox proportional hazard regression. We assessed the interaction between the MELD-Albumin score and the effect of adding a defibrillator with CRT.A total of 752 patients were included in this study, with 291 implanted CRT-P. During a median follow-up of 880 days, 205 patients reached the primary endpoint. MELD-Albumin score was significantly associated with the primary endpoint in the CRT-D group [HR 1.16 (1.09-1.24); P < 0.001] but not in the CRT-P group [HR 1.03 (0.95-1.12); P = 0.49]. There was a significant interaction between the MELD-Albumin score and the effect of CRTD (P = 0.013). The optimal cut-off value of the MELD-Albumin score was 12. For patients with MELD-Albumin ≥ 12, CRT-D was associated with a higher occurrence of the primary endpoint [HR 1.99 (1.10-3.58); P = 0.02], whereas not in patients with MELD-Albumin < 12 [HR 1.19 (0.83-1.70); P = 0.35). Our findings suggest that CRT-D is associated with an excess risk of composite clinical endpoints in HF patients with higher MELD-Albumin score.

Artificial Intelligence in Ventricular Arrhythmias and Sudden Death

Sudden cardiac arrest due to lethal ventricular arrhythmias is a major cause of mortality worldwide and results in more years of potential life lost than any individual cancer. Most of these sudden cardiac arrest events occur unexpectedly in individuals who have not been identified as high-risk due to the inadequacy of current risk stratification tools. Artificial intelligence tools are increasingly being used to solve complex problems and are poised to help with this major unmet need in the field of clinical electrophysiology. By leveraging large and detailed datasets, artificial intelligence-based prediction models have the potential to enhance the risk stratification of lethal ventricular arrhythmias. This review presents a synthesis of the published literature and a discussion of future directions in this field.

Implantable defibrillator therapy and mortality in patients with non-ischaemic dilated cardiomyopathy : An updated meta-analysis and effect on Dutch clinical practice by the Task Force of the Dutch Society of Cardiology

BACKGROUND

Primary prophylactic implantable cardioverter-defibrillators (ICDs) in patients with non-ischaemic cardiomyopathy (NICMP) remains controversial. This study sought to assess the benefit of ICD therapy with or without cardiac resynchronisation therapy (CRT) in patients with NICMP. In addition, data were compared with real-world clinical data to perform a risk/benefit analysis.

METHODS

Relevant randomised clinical trials (RCTs) published in meta-analyses since DANISH, and in PubMed, EMBASE and Cochrane databases from 2016 to 2020 were identified. The benefit of ICD therapy stratified by CRT use was assessed using random effects meta-analysis techniques.

RESULTS

Six RCTs were included in the meta-analysis. Among patients without CRT, ICD use was associated with a 24% reduction in mortality (hazard ratio [HR]: 0.76; 95% confidence interval [CI]: 0.62-0.93; P = 0.008). In contrast, among patients with CRT, a CRT-defibrillator was not associated with reduced mortality (HR: 0.74, 95% CI 0.47-1.16; P = 0.19). For ICD therapy without CRT, absolute risk reduction at 3‑years follow-up was 3.7% yielding a number needed to treat of 27.

CONCLUSION

ICD use significantly improved survival among patients with NICMP who are not eligible for CRT. Considering CRT, the addition of defibrillator therapy was not significantly associated with mortality benefit compared with CRT pacemaker.

Status and Update on Cardiac Resynchronization Therapy Trials

After decades of clinical use, cardiac resynchronization therapy (CRT) can be considered an established therapy. However, there are multiple open questions to be addressed that shall further improve the proportion of patients responding to CRT. Progress in better understanding the relationship between electrical and mechanical disorder in patients with heart failure with ventricular conduction abnormalities is important. This article presents and discusses ongoing studies in different areas of CRT research, including patient selection by novel diagnostic tools, extension of clinical criteria, left ventricular lead positioning and pacing site selection, optimization of CRT delivery and programming, and selection of device type.

Predicting outcome after cardiac resynchronisation therapy defibrillator implantation: the CRT-D Futility score

BACKGROUND

Risk-benefit for cardiac resynchronisation therapy (CRT) defibrillator (CRT-D) over CRT pacemaker remains a matter of debate. We aimed to identify patients with a poor outcome within 1 year of CRT-D implantation, and to develop a CRT-D Futility score.

METHODS

Based on an administrative hospital-discharge database, all consecutive patients treated with prophylactic CRT-D implantation in France (2010-2019) were included. A prediction model was derived and validated for 1-year all-cause death after CRT-D implantation (considered as futility) by using split-sample validation.

RESULTS

Among 23 029 patients (mean age 68±10 years; 4873 (21.2%) women), 7016 deaths were recorded (yearly incidence rate 7.2%), of which 1604 (22.8%) occurred within 1 year of CRT-D implantation. In the derivation cohort (n=11 514), the final logistic regression model included-as main predictors of futility-older age, diabetes, mitral regurgitation, aortic stenosis, history of hospitalisation with heart failure, history of pulmonary oedema, atrial fibrillation, renal disease, liver disease, undernutrition and anaemia. Area under the curve for the CRT-D Futility score was 0.716 (95% CI: 0.698 to 0.734) in the derivation cohort and 0.692 (0.673 to 0.710) in the validation cohort. The Hosmer-Lemeshow test had a p-value of 0.57 suggesting accurate calibration. The CRT-D Futility score outperformed the Goldenberg and EAARN scores for identifying futility. Based on the CRT-D Futility score, 15.9% of these patients were categorised at high risk (predicted futility of 16.6%).

CONCLUSIONS

The CRT-D Futility score, established from a large nationwide cohort of patients treated with CRT-D, may be a relevant tool for optimising healthcare decision-making.

The MADIT-ICD benefit score helps to select implantable cardioverter-defibrillator candidates in cardiac resynchronization therapy

AIMS

The aim of this study is to evaluate whether the MADIT-ICD benefit score can predict who benefits most from the addition of implantable cardioverter-defibrillator (ICD) to cardiac resynchronization therapy (CRT) in real-world patients with heart failure with reduced ejection fraction (HFrEF) and to compare this with selection according to a multidisciplinary expert centre approach.

METHODS AND RESULTS

Consecutive HFrEF patients who received a CRT for a guideline indication at a tertiary care hospital (Ziekenhuis Oost-Limburg, Genk, Belgium) between October 2008 and September 2016, were retrospectively evaluated. The MADIT-ICD benefit groups (low, intermediate, and high) were compared with the current multidisciplinary expert centre approach. Endpoints were (i) sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) and (ii) non-arrhythmic mortality. Of the 475 included patients, 165 (34.7%) were in the lowest, 220 (46.3%) in the intermediate, and 90 (19.0%) in the highest benefit group. After a median follow-up of 34 months, VT/VF occurred in 3 (1.8%) patients in the lowest, 9 (4.1%) in the intermediate, and 13 (14.4%) in the highest benefit group (P < 0.001). Vice versa, non-arrhythmic death occurred in 32 (19.4%) in the lowest, 32 (14.6%) in the intermediate, and 3 (3.3%) in the highest benefit group (P = 0.002). The predictive power for ICD benefit was comparable between expert multidisciplinary judgement and the MADIT-ICD benefit score: Uno's C-statistic 0.69 vs. 0.69 (P = 0.936) for VT/VF and 0.62 vs. 0.60 (P = 0.790) for non-arrhythmic mortality.

CONCLUSION

The MADIT-ICD benefit score can identify who benefits most from CRT-D and is comparable with multidisciplinary judgement in a CRT expert centre.

OUP accepted manuscript

Aims

Cardiac resynchronization therapy (CRT) is an established treatment for heart failure. There is contradictory evidence whether defibrillator capability improves prognosis in patients receiving CRT. We compared the survival of patients undergoing de novo implantation of a CRT with defibrillator (CRT-D) option and CRT with pacemaker (CRT-P) in a large health claims database.

Methods and results

Using health claims data of a major German statutory health insurance, we analysed patients with de novo CRT implantation from 2014 to 2019 without indication for defibrillator implantation for secondary prevention of sudden cardiac death. We performed age-adjusted Cox proportional hazard regression and entropy balancing to calculate weights to control for baseline imbalances. The analysis comprised 847 CRT-P and 2722 CRT-D patients. Overall, 714 deaths were recorded during a median follow-up of 2.35 years. A higher cumulative incidence of all-cause death was observed in the initial unadjusted Kaplan–Meier time-to-event analysis [hazard ratio (HR): 1.63, 95% confidence interval (CI): 1.38–1.92]. After adjustment for age, HR was 1.13 (95% CI: 0.95–1.35) and after entropy balancing 0.99 (95% CI: 0.81–1.20). No survival differences were found in different age groups. The results were robust in sensitivity analyses.

Conclusion

In a large health claims database of CRT implantations performed in a contemporary setting, CRT-P treatment was not associated with inferior survival compared with CRT-D. Age differences accounted for the greatest part of the survival difference that was observed in the initial unadjusted analysis.

Cardiac resynchronization therapy with or without defibrillator in patients with heart failure

Aims

Randomized data on the efficacy/safety of cardiac resynchronization therapy with vs. without defibrillator (CRT-D,-P) in heart failure with reduced ejection fraction (HFrEF) are scarce. We aimed to evaluate survival associated with use of CRT-D vs. CRT-P in a contemporary cohort with HFrEF.

Methods and results

Patients from Swedish HF Registry treated with CRT-D/CRT-P and fulfilling criteria for primary prevention defibrillator use were included. Logistic regression was used to evaluate predictors of CRT-D non-use. All-cause mortality was compared in CRT-D vs. CRT-P by Cox regression in a 1 : 1 propensity-score-matched cohort. Of 1988 patients with CRT, 1108 (56%) had CRT-D and 880 (44%) CRT-P. Older age, higher ejection fraction (EF), female sex, and the lack of referral to HF nurse-led outpatient clinic were major determinants of CRT-D non-use. After matching, 645 CRT-D patients were compared with 645 with CRT-P. The CRT-D use was associated with lower 1- and 3-year all-cause mortality [hazard ratio (HR):0.76, 95% confidence interval (CI):0.58–0.98; HR: 0.82, 95% CI: 0.68–0.99, respectively]. Results were consistent in all pre-specified subgroups except for CRT-D use being associated with lower 3-year mortality in patients with an EF < 30% but not in those with an EF ≥ 30% (HR: 0.73, 95% CI: 0.59–0.89 and HR: 1.24, 95% CI: 0.83–1.85, respectively; P-interaction = 0.02).

Conclusion

In a contemporary HFrEF cohort, CRT-D was associated with lower mortality compared with CRT-P. The CRT-D use was less likely in older patients, females, and in patients not referred to HF nurse-led outpatient clinic. Our findings support the use of CRT-D vs. CRT-P in HFrEF, in particular with severely reduced EF.

Optimized implementation of cardiac resynchronization therapy: a call for action for referral and optimization of care

Cardiac resynchronization therapy (CRT) is one of the most effective therapies for heart failure with reduced ejection fraction and leads to improved quality of life, reductions in heart failure hospitalization rates and all-cause mortality. Nevertheless, up to two-thirds of eligible patients are not referred for CRT. Furthermore, post-implantation follow-up is often fragmented and suboptimal, hampering the potential maximal treatment effect. This joint position statement from three European Society of Cardiology Associations, Heart Failure Association (HFA), European Heart Rhythm Association (EHRA) and European Association of Cardiovascular Imaging (EACVI), focuses on optimized implementation of CRT. We offer theoretical and practical strategies to achieve more comprehensive CRT referral and post-procedural care by focusing on four actionable domains: (i) overcoming CRT under-utilization, (ii) better understanding of pre-implant characteristics, (iii) abandoning the term 'non-response' and replacing this by the concept of disease modification, and (iv) implementing a dedicated post-implant CRT care pathway.

Optimized implementation of cardiac resynchronization therapy: a call for action for referral and optimization of care: A joint position statement from the Heart Failure Association (HFA), European Heart Rhythm Association (EHRA), and European Association of Cardiovascular Imaging (EACVI) of the European Society of Cardiology

Cardiac resynchronization therapy (CRT) is one of the most effective therapies for heart failure with reduced ejection fraction and leads to improved quality of life, reductions in heart failure hospitalization rates and all-cause mortality. Nevertheless, up to two-thirds of eligible patients are not referred for CRT. Furthermore, post-implantation follow-up is often fragmented and suboptimal, hampering the potential maximal treatment effect. This joint position statement from three European Society of Cardiology Associations, Heart Failure Association (HFA), European Heart Rhythm Association (EHRA) and European Association of Cardiovascular Imaging (EACVI), focuses on optimized implementation of CRT. We offer theoretical and practical strategies to achieve more comprehensive CRT referral and post-procedural care by focusing on four actionable domains: (i) overcoming CRT under-utilization, (ii) better understanding of pre-implant characteristics, (iii) abandoning the term 'non-response' and replacing this by the concept of disease modification, and (iv) implementing a dedicated post-implant CRT care pathway.

Cardiac resynchronization therapy with or without defibrillation: a long-standing debate

Cardiac resynchronization therapy (CRT) was shown to improve cardiac function, reduce heart failure hospitalizations, improve quality of life and prolong survival in patients with severe left ventricular dysfunction and intraventricular conduction disturbances, mainly left bundle branch block, on optimal medical therapy with ACE-inhibitors, β-blockers and mineralocorticoid receptor antagonists up-titrated to maximum tolerated evidence-based doses. CRT can be achieved by means of pacemaker systems (CRT-P) or devices with defibrillation capabilities (CRT-D). CRT-Ds offer an undoubted advantage in the prevention of arrhythmic death, but such an advantage may be of lesser degree in non-ischemic heart failure aetiologies. Moreover, the higher CRT-D hardware complexity compared to CRT-P may predispose to device/lead malfunctions and the higher current drainage may cause a shorter battery duration with consequent premature replacements and the well-known incremental complications. In a period of financial constraints, also device costs should be carefully evaluated, with recent reports suggesting that CRT-Ps may be favoured over CRT-Ds in patients with non-ischemic cardiomyopathy and no prior history of cardiac arrhythmias from a cost-effectiveness point of view. The choice between a CRT-P or a CRT-D device should be patient-tailored whenever straightforward defibrillator indications are not present. The Goldenberg score may facilitate this decision-making process in ambiguous settings. Age, comorbidities, kidney disease, atrial fibrillation, advanced functional class, inappropriate therapy risk, implantable device infections and malfunctions are factors potentially reducing the expected benefit from defibrillating capabilities. Future prospective, randomized controlled trials are warranted to directly compare the efficacy and safety of CRT-Ps and CRT-Ds.

Application of the heart failure meta-score to predict prognosis in patients with cardiac resynchronization defibrillators

BACKGROUND

The Heart Failure (HF) Meta-score may be useful in predicting prognosis in patients with primary prevention cardiac resynchronization defibrillators (CRT-D) considering the competing risk of appropriate defibrillator shock versus mortality.

METHODS

Data from 648 consecutive patients from two centers were used for the evaluation of the performance of the HF Meta-score. The primary endpoint was mortality and the secondary endpoint was time to first appropriate implantable cardioverter-defibrillator (ICD) shock or death without prior appropriate ICD shock. Fine-Gray model was used for competing risk regression analysis.

RESULTS

In the entire cohort, 237 patients died over a median follow-up of 5.2 years. Five-year cumulative incidence of mortality ranged from 12% to 53%, for quintiles 1 through 5 of the HF Meta-score, respectively (log-rank P < 0.001). Compared with the lowest quintile, mortality risk was higher in the highest quintile (HR 6.9; 95%CI 3.7-12.8). The HF Meta-score had excellent calibration, accuracy, and good discrimination in predicting mortality (C-statistic 0.76 at 1-year and 0.71 at 5-year). The risk of death without appropriate ICD shock was higher in risk quintile 5 compared to quintile 1 (sub HR 5.8; 95%CI 3.1-11.0, P < 0.001).

CONCLUSIONS

Our study demonstrated a good ability of the HF Meta-score to predict survival in HF patients treated with CRT-D as primary prevention. The HF Meta-score proved to be useful in identifying a subgroup with a significantly poor prognosis despite a CRT-D.

The benefits of defibrillator in heart failure patients with cardiac resynchronization therapy: A meta-analysis

BACKGROUND

Current guidelines did not provide recommendations on indications of an additional implantable cardioverter-defibrillator (ICD) to patients receiving cardiac resynchronization therapy (CRT), and it still remains controversial due to lack of evidence from randomized controlled trials.

METHOD

PubMed, Embase, and Cochrane CENTRAL from the inception to May 2020 were systematically screened for studies reporting on the comparison of cardiac resynchronization therapy with defibrillator (CRT-D) and cardiac resynchronization therapy with pacemaker (CRT-P), focusing on the adjusted hazard ratio (aHR) of all-cause mortality. We pooled the effects using a random-effect model.

RESULTS

Twenty-one studies encompassing 69,919 patients were included in this meta-analysis. With no restriction to characteristics of including population, CRT-D was associated with a lower all-cause mortality compared with CRT-P significantly (aHR: 0.80, 95% confidence interval [CI]: 0.74-0.87, I²  = 36.8%, p < .001). This mortality benefit was also observed in patients with ischemic cardiomyopathy (aHR: 0.74, 95% CI: 0.64-0.86, I²  = 0%, p < .001). However, there is no significant difference in patients with nonischemic cardiomyopathy (NICM) (aHR: 0.91, 95% CI: 0.82-1.01, I²  = 0%, p = .087), older age (age ≥75 years, aHR: 0.96, 95% CI: 0.83-1.12, I²  = 0%, p = .610). Subgroup analysis was performed and indicated the survival benefit of CRT-D for primary prevention compared with CRT-P (aHR: 0.87, 95% CI: 0.79-0.95, I²  = 0%, p = .003).

CONCLUSION

After adjusted the differences in clinical characteristics, additional ICD therapy was associated with a reduced all-cause mortality in patients receiving CRT. However, our work suggested that additional ICD may not be applied to elderly (≥75 years) or patients with NICM.

Implantable Cardioverter-defibrillator Utilization and Its Outcomes in Korea: Data from Korean Acute Heart Failure Registry

BACKGROUND

There are sparse data on the utilization rate of implantable cardioverter-defibrillator (ICD) and its beneficial effects in Korean patients with heart failure with reduced left ventricular ejection fraction (LVEF).

METHODS

Among 5,625 acute heart failure (AHF) patients from 10 tertiary university hospitals across Korea, 485 patients with reassessed LVEF ≤ 35% at least 3 months after the index admission were enrolled in this study. The ICD implantation during the follow-up was evaluated. Mortality was compared between patients with ICDs and age-, sex-, and follow-up duration matched control patients.

RESULTS

Among 485 patients potentially indicated for an ICD for primary prevention, only 56 patients (11.5%) underwent ICD implantation during the follow-up. Patients with ICD showed a significantly lower all-cause mortality compared with their matched control population: adjusted hazard ratio (HR) (95% confidence interval [CI]) = 0.39 (0.16-0.92), P = 0.032. The mortality rate was still lower in the ICD group after excluding patients with cardiac resynchronization therapy (adjusted HR [95% CI] = 0.09 [0.01-0.63], P = 0.015). According to the subgroup analysis for ischemic heart failure, there was a significantly lower all-cause mortality in the ICD group than in the no-ICD group (HR [95% CI] = 0.20 [0.06-0.72], P = 0.013), with a borderline statistical significance (interaction P = 0.069).

CONCLUSION

Follow-up data of this large, multicenter registry suggests a significant under-utilization of ICD in Korean heart failure patients with reduced LVEF. Survival analysis implies that previously proven survival benefit of ICD in clinical trials could be extrapolated to Korean patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01389843.

Long-Term Survival After Implantable Cardiac Defibrillator Therapy According to Sex: A Propensity Matched Study

Background: Whether the sex factor influences the benefit of the implantable cardioverter-defibrillator (ICD) for the prevention of sudden death remains a subject of debate. Using a prospective registry, we sought to analyze the survival and time to first ICD therapy according to sex. Materials and Methods: Retrospective analysis of a prospective cohort of patients undergoing an ICD implant from 2008 to 2019. Data about time to first appropriate therapy, type of therapy administered, and incidence and causes of mortality were collected. Results: Among 756 ICD patients, 150 (19.8%) were women. Women were younger (51 ± 15 years vs. 61 ± 14 years; p < 0.001) and showed a lower rate of ischemic cardiomyopathy (23% vs. 54%; p < 0.001) and atrial fibrillation (12% vs. 19%; p = 0.05). Women had higher left ventricular ejection fraction (39% ± 17% vs. 35% ± 13%) and showed more frequently left bundle branch block (39% vs. 28%, p = 0.027). The rate of primary prevention (68% vs. 59.6%; p = 0.058) and cardiac resynchronization therapy (27% vs. 19%, p = 0.02) were higher in women. After a median follow-up of 46 months (3382 patient-years), the incidence of both the primary combined endpoint of mortality/transplant (20% vs. 29%; logrank = 0.031) and ICD therapies (27% vs. 34%; p = 0.138) were lower in women. According to the propensity score-matching analysis, no differences were observed between both sexes with respect to the incidence of mortality/transplant (24.8% vs. 28.6%; logrank = 0.88), ICD therapies (28% vs. 27%; logrank = 0.17), and main cause of death (heart failure [HF]). Conclusions: The clinical characteristics at the moment of ICD implant are different between sexes. After adjusting them, both sexes equally benefit from the ICD. HF is the main cause of mortality both in men and women.

Biventricular pacemaker and defibrillator implantation in patients with chronic heart failure in China

Aims

This study aims to investigate the current status of biventricular pacemaker and defibrillator implantation in chronic heart failure (CHF) patients with indications for primary prevention of sudden cardiac death (SCD) in China and the effects of cardiac resynchronization therapy (CRT)‐pacemaker (P) and CRT‐defibrillator (D) implantation on the clinical prognosis of CHF among patients undergoing CRT.

Methods and results

Overall, 798 consecutive patients who had devices implanted (implantable cardioverter defibrillator: 199, CRT‐D: 362, and CRT‐P: 237) from May 2012 to July 2013 in POSCD‐China, a multicentric prospective cohort study, were enrolled. The primary endpoint was all‐cause death, and the secondary endpoint was SCD. In total, 71.3% of patients had non‐ischaemic CHF. The mean follow‐up time was 27.7 ± 12.0 months, and death occurred in 158 cases, with 35 cases of SCD. CHF was the main cause of death (68.4%), followed by sudden death (22.2%). In the CRT‐P group, the SCD rate was 8.0%, which was much higher than that in the CRT‐D (3.3%) and implantable cardioverter defibrillator (2.0%) groups. No significant differences were identified in the all‐cause death rate between the CRT‐D and CRT‐P groups (CRT‐D vs. CRT‐P, 20.4% vs. 19.4%, P = 0.840).

Conclusions

In China, among CHF patients with indications for primary prevention of SCD who received device implantation, non‐ischaemic CHF was the main aetiology, and the most important cause of death was heart failure. No differences in all‐cause death were observed between the CRT‐D and CRT‐P groups, but the CRT‐D group had a lower SCD rate than the CRT‐P group.

Cardiac resynchronization therapy pacemaker or cardiac resynchronization therapy defibrillator: what determines the choice?-findings from the ESC CRT Survey II

AIMS

The decision to implant a cardiac resynchronization therapy pacemaker (CRT-P) or a cardiac resynchronization therapy defibrillator (CRT-D) may be challenging. There are no clear guideline recommendations as no randomized study of cardiac resynchronization therapy (CRT) has been designed to compare the effects of CRT-P with those of CRT-D on patients' outcomes. In the CRT Survey II, we studied patient and implantation centre characteristics associated with the choice of CRT-P vs. CRT-D.

METHODS AND RESULTS

Clinical practice data from 10 692 patients undergoing CRT implantation of whom 7467 (70%) patients received a CRT-D and 3225 (30%) received a CRT-P across 42 ESC countries were collected and analysed between October 2015 and January 2017. Factors favouring the selection of CRT-P implantation included age >75 years, female gender, non-ischaemic heart failure (HF) aetiology, New York Heart Association functional Class III/IV symptoms, left ventricular ejection fraction >25%, atrial fibrillation, atrioventricular (AV) block II/III, and implantation in a university hospital.

CONCLUSION

In a large cohort from the CRT Survey II, we found that patients allocated to receive CRT-P exhibited particular phenotypes with more symptomatic HF, more frequent comorbidities, advanced age, female gender, non-ischaemic HF aetiology, atrial fibrillation, and evidence of AV block. There were substantial differences in the proportion of patients allocated to receive CRT-P vs. CRT-D between countries.

Impact of age on mid-term clinical outcomes and left ventricular reverse remodeling after cardiac resynchronization therapy

INTRODUCTION

The number of heart failure (HF) patients has been rapidly increasing in Japan, and considering the most explosive aging occurring in Asia, the management of elderly HF patients and longer life expectancy are critical issues. The aim of the present study was to evaluate whether the mid-term prognosis after cardiac resynchronization therapy (CRT) implantation was influenced by age and to investigate, in detail, the difference in the change ratio of echocardiographic parameters according to the age group of interest.

METHODS AND RESULTS

This retrospective analysis included 173 patients who underwent CRT implantation in our hospital from February 2008 to March 2019. Eighty patients (46%) were classified into the elderly group (≥75 years) and the rest in the non-elderly group. The study population was also classified with propensity score matching. The mid-term prognosis including all-cause death and hospitalization for HF, and the ratio of CRT responders were compared between the 2 groups. CRT response was defined as left ventricular (LV) end-systolic volume reduction ≥15% at follow-up echocardiography within a year. During a median follow-up of 1057 [interquartile range: 412, 2107] days, adverse events were not significantly different between the 2 groups before and after matching (before matching; all-cause death: log-rank p = 0.323, hospitalization for HF: log-rank p = 0.376, after matching; all-cause death: log-rank p = 0.325, hospitalization for HF: log-rank p = 0.516). Moreover, the rate of CRT responders was not significantly different between the 2 groups before and after matching (before matching, p = 0.718; after matching, p = 0.666).

CONCLUSIONS

In elderly HF patients, CRT provided the same clinical benefits as in non-elderly HF patients, furthermore, there was a similar trend in LV reverse remodeling between the 2 groups. The present study demonstrated that the indication of CRT implantation should not be determined by age.

Mortality and cardiac resynchronization therapy with or without defibrillation in primary prevention

AIMS

Cardiac resynchronization therapy with (CRTD) or without (CRTP) defibrillator is recommended in selected patient with systolic chronic heart failure and wide QRS. There is no guideline firmly indicating choice between CRTP and CRTD in primary prevention, particularly in older patients.

METHODS AND RESULTS

Based on the French administrative hospital-discharge database, information was collected from 2010 to 2017 for all patients implanted with CRTP or CRTD in primary prevention. Outcome analyses were undertaken in the total study population and in propensity-matched samples. During follow-up (913 days, SD 841, median 701, IQR 151-1493), 45 697 patients were analysed (CRTP 19 266 and CRTD 26 431). Incidence rate (%patient/year) of all-cause mortality was higher in CRTP patients (11.6%) than in CRTD patients (6.8%) [hazard ratio (HR) 1.70, 95% confidence interval (CI) 1.63-1.76, P < 0.001]. After propensity-matched analyses, mortality of patients over 75 years old with non-ischaemic cardiomyopathy (NICM) was not different with CRTP and CRTD (HR 0.93, 95% CI 0.80-1.09, P = 0.39). The CRTP patients under 75 years old with NICM had a higher mortality than CRTD patients (HR 1.22, 95% CI 1.03-1.45, P = 0.02). Mortality rate was also higher with CRTP than with CRTD irrespectively of age in patients with ischaemic cardiomyopathy (ICM) (<75 years old: HR 1.22, 95% CI 1.08-1.37, P = 0.01; ≥75 years old: HR 1.13, 95% CI 1.04-1.22, P = 0.003).

CONCLUSION

In this real-life study, CRTD was associated with a significantly lower all-cause mortality than CRTP in patients with ICM and in patients with NICM under 75 years old. Patients over 75 years old with NICM did not have lower mortality with primary prevention CRTD implantation.

Trends in the use of implantable cardioverter-defibrillator and cardiac resynchronization therapy device in advancing age: Analysis of the Japan cardiac device treatment registry database

BACKGROUND

Trends of de novo implantation of cardiac implantable electronic devices (CIEDs) including implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy with a defibrillator (CRT-D) or pacemaker (CRT-P) in advancing age are unknown.

METHODS

Analysis of data from the Japan cardiac device treatment registry (JCDTR) with an implantation date between January 2006 and December 2016 was performed focusing on advancing age of ≧75 years.

RESULTS

The cohort included 17 564 ICD, 9470 CRT-D and 1087 CRT-P recipients for de novo implantation. The rate of patients ≧75 years of age increased from 17.1% to 20.5% in ICD implantation (P = .052), from 19.7% to 30.0% in CRT-D implantation (P < .0001), and from 40.0% to 64.0% in CRT-P implantation (P = .17). There was an apparent increase in the percentage of nonischemic patients aged ≧75 years receiving ICD (10.9% in 2006 to 16.4% in 2016, P = .0008) and CRT-D (17.1% in 2006 to 27.8% in 2016, P = .0001). The implantation for primary prevention ICD (P = .059) and CRT-D (P = .012) was also associated with a temporal increase in the percentage of patients aged ≧75 years.

CONCLUSIONS

Proportion of patients ≧75 years of age for de novo CIED implantation gradually increased from 2006 to 2016, presumably because of the growing number of nonischemic cardiomyopathy and heart failure patients requiring primary prevention of sudden cardiac death.

Myocardial fibrosis and the effect of primary prophylactic defibrillator implantation in patients with non-ischemic systolic heart failure-DANISH-MRI

AIMS

Patients with non-ischemic systolic heart failure have an increased risk of sudden cardiac death (SCD). Myocardial fibrosis, detected as late gadolinium enhancement (LGE) with cardiac magnetic resonance (CMR), has been shown to predict all-cause mortality. We hypothesized that LGE can identify patients with non-ischemic heart failure who will benefit from ICD implantation.

METHODS AND RESULTS

In this prospective observational sub-study of the Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic Heart Failure on Mortality (DANISH), 252 patients underwent CMR. LGE was quantified by the full width/half maximum method. The primary endpoint was all-cause mortality. LGE could be adequately assessed in 236 patients, median age was 61 years and median duration of heart failure was 14 months; there were 108 patients (46%) randomized to ICD. Median follow-up time was 5.3 years. Median left ventricular ejection fraction on CMR was 35%. In all, 50 patients died. LGE was present in 113 patients (48%). The presence of LGE was an independent predictor of all-cause mortality (HR 1.82; 95% CI 1.002-3.29; P = .049) after adjusting for known cardiovascular risk factors. ICD implantation did not impact all-cause mortality, for either patients with LGE (HR 1.18; 95% CI 0.59-2.38; P = .63), or for patients without LGE (HR 1.00; 95% CI 0.39-2.53; P = .99), (P for interaction =0.79).

CONCLUSION

In patients with non-ischemic systolic heart failure, LGE predicted all-cause mortality. However, in this cohort, LGE did not identify a group of patients who survived longer by receiving an ICD.

Implantable cardioverter defibrillator and cardiac resynchronization therapy use in New Zealand (ANZACS-QI 33)

BACKGROUND

The ANZACS-QI Cardiac Implanted Device Registry (ANZACS-QI DEVICE) collects nationwide data on cardiac implantable electronic devices in New Zealand (NZ). We used the registry to describe contemporary NZ use of implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT).

METHODS

All ICD and CRT Pacemaker implants recorded in ANZACS-QI DEVICE between 1 January 2014 and 31 December 2017 were analyzed.

RESULTS

Of 1579 ICD implants, 1152 (73.0%) were new implants, including 49.0% for primary prevention and 51.0% for secondary prevention. In both groups, median age was 62 years and patients were predominantly male (81.4% and 79.2%, respectively). Most patients receiving a primary prevention ICD had a history of clinical heart failure (80.4%), NYHA class II-III symptoms (77.1%) and LVEF ≤35% (96.9%). In the secondary prevention ICD cohort, 88.4% were for sustained ventricular tachycardia or survived cardiac arrest from ventricular arrhythmia. Compared to primary prevention CRT Defibrillators (n = 155), those receiving CRT Pacemakers (n = 175) were older (median age 74 vs 66 years) and more likely to be female (38.3% vs 19.4%). Of the 427 (27.0%) ICD replacements (mean duration 6.3 years), 46.6% had received appropriate device therapy while 17.8% received inappropriate therapy. The ICD implant rate was 119 per million population with regional variation in implant rates, ratio of primary prevention ICD implants, and selection of CRT modality.

CONCLUSION

In contemporary NZ practice three-quarters of ICD implants were new implants, of which half were for primary prevention. The majority met current guideline indications. Patients receiving CRT pacemaker were older and more likely to be female.

Time trends in sudden cardiac death risk in heart failure patients with cardiac resynchronization therapy: a systematic review

Aims

While data from randomized trials suggest a declining incidence of sudden cardiac death (SCD) among heart failure patients, the extent to which such a trend is present among patients with cardiac resynchronization therapy (CRT) has not been evaluated. We therefore assessed changes in SCD incidence, and associated factors, in CRT recipients over the last 20 years.

Methods and results

Literature search from inception to 30 April 2018 for observational and randomized studies involving CRT patients, with or without defibrillator, providing specific cause-of-death data. Sudden cardiac death was the primary endpoint. For each study, rate of SCD per 1000 patient-years of follow-up was calculated. Trend line graphs were subsequently constructed to assess change in SCD rates over time, which were further analysed by device type, patient characteristics, and medical therapy. Fifty-three studies, comprising 22 351 patients with 60 879 patient-years of follow-up and a total of 585 SCD, were included. There was a gradual decrease in SCD rates since the early 2000s in both randomized and observational studies, with rates falling more than four-fold. The rate of decline in SCD was steeper than that of all-cause mortality, and accordingly, the proportion of deaths which were due to SCD declined over the years. The magnitude of absolute decline in SCD was more prominent among CRT-pacemaker (CRT-P) patients compared to those receiving CRT-defibrillator (CRT-D), with the difference in SCD rates between CRT-P and CRT-D decreasing considerably over time. There was a progressive increase in age, use of beta-blockers, and left ventricular ejection fraction, and conversely, a decrease in QRS duration and antiarrhythmic drug use.

Conclusion

Sudden cardiac death rates have progressively declined in the CRT heart failure population over time, with the difference between CRT-D vs. CRT-P recipients narrowing considerably.

The European Society of Cardiology Cardiac Resynchronization Therapy Survey II: A comparison of cardiac resynchronization therapy implantation practice in Europe and France

BACKGROUND

The first European Cardiac Resynchronization Therapy (CRT) Survey, conducted in 2008-2009, showed considerable variations in guideline adherence and implantation practice. A second prospective survey (CRT Survey II) was then performed to describe contemporary clinical practice regarding CRT among 42 European countries.

AIM

To compare the characteristics of French CRT recipients with the overall European population of CRT Survey II.

METHODS

Demographic and procedural data from French centres recruiting all consecutive patients undergoing either de novo CRT implantation or an upgrade to a CRT system were collected and compared with data from the European population.

RESULTS

A total of 11,088 patients were enrolled in CRT Survey II, 754 of whom were recruited in France. French patients were older (44.7% aged≥75 years vs 31.1% in the European group), had less severe heart failure symptoms, a higher baseline left ventricular ejection fraction and fewer co-morbidities. Additionally, French patients had a shorter intrinsic QRS duration (19.1% had a QRS<130ms vs 12.3% in the European cohort). Successful implantation rates were similar, but procedural and fluoroscopy times were shorter in France. French patients were more likely to receive a CRT pacemaker than European patients overall. Of note, antibiotic prophylaxis was reported to be administered less frequently in France, and a higher rate of early device-related infection was observed. Importantly, French patients were less likely to receive optimal drugs for treating heart failure at hospital discharge.

CONCLUSION

This study highlights contemporary clinical practice in France, and describes substantial differences in patient selection, implantation procedure and outcomes compared with the other European countries participating in CRT Survey II.

Association Between Use of Primary-Prevention Implantable Cardioverter-Defibrillators and Mortality in Patients With Heart Failure

Background:

Most randomized trials on implantable cardioverter-defibrillator (ICD) use for primary prevention of sudden cardiac death in heart failure with reduced ejection fraction enrolled patients >20 years ago. We investigated the association between ICD use and all-cause mortality in a contemporary heart failure with reduced ejection fraction cohort and examined relevant subgroups.

Methods:

Patients from the Swedish Heart Failure Registry fulfilling the European Society of Cardiology criteria for primary-prevention ICD were included. The association between ICD use and 1-year and 5-year all-cause and cardiovascular (CV) mortality was assessed by Cox regression models in a 1:1 propensity score–matched cohort and in prespecified subgroups.

Results:

Of 16 702 eligible patients, only 1599 (10%) had an ICD. After matching, 1305 ICD recipients were compared with 1305 nonrecipients. ICD use was associated with a reduction in all-cause mortality risk within 1 year (hazard ratio, 0.73 [95% CI, 0.60–0.90]) and 5 years (hazard ratio, 0.88 [95% CI, 0.78–0.99]). Results were consistent in all subgroups including patients with versus without ischemic heart disease, men versus women, those aged <75 versus ≥75 years, those with earlier versus later enrollment in the Swedish heart failure registry, and patients with versus without cardiac resynchronization therapy.

Conclusions:

In a contemporary heart failure with reduced ejection fraction population, ICD for primary prevention was underused, although it was associated with reduced short- and long-term all-cause mortality. This association was consistent across all the investigated subgroups. These results call for better implementation of ICD therapy.

Sleep-disordered breathing and effectiveness of cardiac resynchronization therapy in heart failure patients: gender differences?

OBJECTIVES

This study evaluated heart failure (HF) patients who underwent cardiac resynchronization therapy (CRT) and who had device-documented sleep-disordered breathing (SDB). We found gender differences in acute changes in SDB due to CRT impact.

BACKGROUND

SDB typically occurs in HF patients. However, the role of SDB and its response to CRT in HF patients, as well as the relation with gender are currently not fully researched.

METHODS

Among 63 consecutive patients who received CRT with an SDB algorithm, 23 patients documented SDB at one-month cardiac device interrogation and represented our population. We defined a Sleep apnoea Severity SCore(SSSC), and consequently, patients were categorized to have mild, moderate, and severe sleep apnoea syndrome divided into two groups: Group-1: 18 males (78%); Group-2: 5 females (22%). We evaluated the variation of apnoea burden and CRT response based on gender differences.

RESULTS

A significantly higher proportion of patients in the male group were non-responders to CRT at 12-months follow-up (p = 0.076) while in the female population 5/5 patients (100%) were responders to CRT at the same follow-up time (p = 0.021). Among Group-2 subjects, we documented a significant linear decrease in SSSC(p > 0,01) while in Group-1 the CRT effect on SSSC was variable. At 12-months follow-up, the difference in SSSC between the two groups was statistically significant (p < 0.001).

CONCLUSIONS

Our study reports a correlation between CRT response and sleep apnoea burden considering gender differences. In particular, HF-women responders to CRT demonstrate a significant linear decrease in sleep apnoea burden determined through a device algorithm, when compared to a similar male population. Further research is needed to confirm these findings.

Improving Cardiac Resynchronisation Therapy

CRT is a cornerstone of therapy for patients with heart failure and reduced ejection fraction. By restoring left ventricular (LV) electrical and mechanical synchrony, CRT can reduce mortality, improve LV function and reduce heart failure symptoms. Since its introduction, many advances have been made that have improved the delivery of and enhanced the response to CRT. Improving CRT outcomes begins with proper patient selection so CRT is delivered to all populations that could benefit from it, and limiting the implantation of CRT in those with a small chance of response. In addition, advancements in LV leads and delivery technologies coupled with multimodality imaging and electrical mapping have enabled operators to place coronary sinus leads in locations that will optimise electrical and mechanical synchrony. Finally, new pacing strategies using LV endocardial pacing or His bundle pacing have allowed for CRT delivery and improved response in patients with poor coronary sinus anatomy or lack of response to traditional CRT.

Long-term clinical outcomes of cardiac resynchronization therapy with or without defibrillation: impact of the aetiology of cardiomyopathy

Aims

There is a continuing debate as to whether cardiac resynchronization therapy-defibrillation (CRT-D) is superior to CRT-pacing (CRT-P), particularly in patients with non-ischaemic cardiomyopathy (NICM). We sought to quantify the clinical outcomes after primary prevention of CRT-D and CRT-P and identify whether these differed according to the aetiology of cardiomyopathy.

Methods and results

Analyses were undertaken in the total study population of patients treated with CRT-D (n = 551) or CRT-P (n = 999) and in propensity-matched samples. Device choice was governed by the clinical guidelines in the United Kingdom. In univariable analyses of the total study population, for a maximum follow-up of 16 years (median 4.7 years, interquartile range 2.4–7.1), CRT-D was associated with a lower total mortality [hazard ratio (HR) 0.72] and the composite endpoints of total mortality or heart failure (HF) hospitalization (HR 0.72) and total mortality or hospitalization for major adverse cardiac events (MACE; HR 0.71) (all P < 0.001). After propensity matching (n = 796), CRT-D was associated with a lower total mortality (HR 0.72) and the composite endpoints (all P < 0.01). When further stratified according to aetiology, CRT-D was associated with a lower total mortality (HR 0.62), total mortality or HF hospitalization (HR 0.63), and total mortality or hospitalization for MACE (HR 0.59) (all P < 0.001) in patients with ischaemic cardiomyopathy (ICM). There were no differences in outcomes between CRT-D and CRT-P in patients with NICM.

Conclusion

In this study of real-world clinical practice, CRT-D was superior to CRT-P with respect to total mortality and composite endpoints, independent of known confounders. The benefit of CRT-D was evident in ICM but not in NICM.

Implantable Cardiac Electronic Devices in the Elderly Population

The use of cardiac implantable electronic devices in the management of patients with heart rhythm conditions is well established. As the population ages, the use of cardiac implantable electronic devices in the elderly is likely to increase. This review provides a summary of the indications, implantation considerations and pragmatic advice on how to approach the use of these devices in this group of patients.

Very long-term survival and late sudden cardiac death in cardiac resynchronization therapy patients

Aims

The very long-term outcome of patients who survive the first few years after receiving cardiac resynchronization therapy (CRT) has not been well described thus far. We aimed to provide long-term outcomes, especially with regard to the occurrence of sudden cardiac death (SCD), in CRT patients without (CRT-P) and with defibrillator (CRT-D).

Methods and results

A total of 1775 patients, with ischaemic or non-ischaemic dilated cardiomyopathy, who were alive 5 years after CRT implantation, were enrolled in this multicentre European observational cohort study. Overall long-term mortality rates and specific causes of death were assessed, with a focus on late SCD. Over a mean follow-up of 30 months (interquartile range 10–42 months) beyond the first 5 years, we observed 473 deaths. The annual age-standardized mortality rates of CRT-D and CRT-P patients were 40.4 [95% confidence interval (CI) 35.3–45.5] and 97.2 (95% CI 85.5–109.9) per 1000 patient-years, respectively. The adjusted hazard ratio (HR) for all-cause mortality was 0.99 (95% CI 0.79–1.22). Twenty-nine patients in total died of late SCD (14 with CRT-P, 15 with CRT-D), corresponding to 6.1% of all causes of death in both device groups. Specific annual SCD rates were 8.5 and 5.8 per 1000 patient-years in CRT-P and CRT-D patients, respectively, with no significant difference between groups (adjusted HR 1.0, 95% CI 0.45–2.44). Death due to progressive heart failure represented the principal cause of death (42.8% in CRT-P patients and 52.6% among CRT-D recipients), whereas approximately one-third of deaths in both device groups were due to non-cardiovascular death.

Conclusion

In this first description of very long-term outcomes among CRT recipients, progressive heart failure death still represented the most frequent cause of death in patients surviving the first 5 years after CRT implant. In contrast, SCD represents a very low proportion of late mortality irrespective of the presence of a defibrillator.

Prophylactic implantable cardioverter-defibrillator in the very elderly

Aims

Current guidelines do not propose any age cut-off for the primary prevention implantable cardioverter-defibrillator (ICD). However, the risk/benefit balance in the very elderly population has not been well studied.

Methods and results

In a multicentre French study assessing patients implanted with an ICD for primary prevention, outcomes among patients aged ≥80 years were compared with <80 years old controls matched for sex and underlying heart disease (ischaemic and dilated cardiomyopathy). A total of 300 ICD recipients were enrolled in this specific analysis, including 150 patients ≥80 years (mean age 81.9 ± 2.0 years; 86.7% males) and 150 controls (mean age 61.8 ± 10.8 years). Among older patients, 92 (75.6%) had no more than one associated comorbidity. Most subjects in the elderly group got an ICD as part of a cardiac resynchronization therapy procedure (74% vs. 46%, P < 0.0001). After a mean follow-up of 3.0 ± 2 years, 53 patients (35%) in the elderly group died, including 38.2% from non cardiovascular causes of death. Similar proportion of patients received ≥1 appropriate therapy (19.4% vs. 21.6%; P = 0.65) in the elderly group and controls, respectively. There was a trend towards more early perioperative events (P = 0.10) in the elderly, with no significant increase in late complications (P = 0.73).

Conclusion

Primary prevention ICD recipients ≥80 years in the real world had relatively low associated comorbidity. Rates of appropriate therapies and device-related complications were similar, compared with younger subjects. Nevertheless, the inherent limitations in interpreting observational data on this particular competing risk situation call for randomized controlled trials to provide definitive answers. Meanwhile, a careful multidisciplinary evaluation is needed to guide patient selection for ICD implantation in the elderly population.

Beyond pharmacological treatment: an insight into therapies that target specific aspects of heart failure pathophysiology

Heart failure is a common syndrome associated with substantial morbidity and mortality. The management of symptoms and the strategies for improving prognosis have largely been based on pharmacological treatments. The pathophysiology of heart failure is complex because of the multiple causes responsible for this syndrome. This Series paper presents some examples of advances in heart failure management, in which the treatment specifically targets the underlying pathophysiological mechanisms responsible for the symptoms. These treatments include treatment of electromechanical dyssynchrony and dysrhythmia by cardiac resynchronisation and implantable cardioverter-defibrillators; neurohumoral modification by baroreflex and vagal stimulation; prevention of adverse cardiac remodelling by interatrial shunts; and finally targeting the myocardium directly by cell therapy in an attempt to regenerate new myocardial cells.