Effectiveness Of Implantable Cardioverter Defibrillators Research Articles

Effect of Implantable Cardioverter-defibrillators in Nonischemic Heart Failure According to Background Medical Therapy: Extended Follow-up of the DANISH Trial

The Heart Failure Collaboratory (HFC) score integrates types and dosages of guideline-directed pharmacotherapies for heart failure (HF) with reduced ejection fraction (HFrEF). We examined the effects of cardioverter-defibrillator (ICD) implantation according to the modified HFC (mHFC) score in 1116 patients with nonischemic HFrEF from the Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic HF on Mortality (DANISH). Patients were assigned scores for renin-angiotensin-system inhibitors, beta-blockers and mineralocorticoid receptor antagonists (0, no use; 1, < 50% of maximum dosage; 2, ≥ 50% of maximum dosage). The maximum score was 6, corresponding to ≥ 50% of maximum dosage for all therapies. The median baseline mHFC score was 4, and the median follow-up was 9.5 years. Compared with an mHFC score of 3-4, an mHFC score of 1-2 was associated with a higher rate of all-cause death (mHFC = 1-2: adjusted HR 1.67 [95% CI, 1.23-2.28]; mHFC = 3-4, reference; mHFC = 5-6: adjusted HR 1.07 [95% CI, 0.87-1.31]). ICD implantation did not reduce all-cause death compared with control (reference) (HR 0.89 [95% CI, 0.74-1.08]), regardless of mHFC score (mHFC = 1-2: HR 0.98 [95% CI, 0.56-1.71]; mHFC = 3-4: HR 0.89 [95% CI,0.66-1.20]; mHFC = 5-6: HR 0.85 [95% CI, 0.64-1.12]; Pinteraction, 0.65). Similarly, ICD implantation did not reduce cardiovascular death (HR 0.87 [95% CI, 0.70-1.09]), regardless of mHFC score (Pinteraction, 0.59). The ICD group had a lower rate of sudden cardiovascular death (HR, 0.60 [95% CI,0.40-0.92]); this association was not modified by mHFC score (Pinteraction, 0.35). Lower mHFC scores were associated with higher rates of all-cause death. ICD implantation did not result in an overall survival benefit in patients with nonischemic HFrEF, regardless of mHFC score.

Cost effectiveness of implantable cardioverter defibrillators for 1.5 primary prevention of sudden cardiac arrest in China: an analysis from the Improve SCA study

Objectives Implantable cardioverter defibrillator (ICDs) for primary prevention (PP) of sudden cardiac arrest (SCA) is underutilized in developing countries. The Improve SCA study has identified a subset of 1.5 primary prevention (1.5PP) patients with a higher risk of SCA and a significant mortality benefit from ICD therapy. From the perspective of China’s healthcare system, we evaluated the cost-effectiveness of ICD therapy vs. no ICD therapy among 1.5PP patients with a view to informing clinical and policy decisions. Methods A published Markov model was adjusted and verified to simulate the course of the disease and describe different health states of 1.5PP patients. The patient characteristics, mortality, utility and complication estimates were obtained from the Improve SCA study and other literature. Cost inputs were sourced from government tender prices, medical service prices and clinical experts’ surveys in 9 Chinese public hospitals. For both ICD and no ICD therapy, the total medical costs and quality-adjusted life-years (QALYs) were modelled over a lifetime horizon and the incremental cost-effectiveness ratio (ICER) was calculated. Deterministic and probabilistic sensitivity analyses were performed to assess the uncertainty of the model parameters. We used the willingness-to-pay (WTP) threshold recommended by China Guidelines for Pharmacoeconomic Evaluations, one to three times China’s GDP per capita (CNY85,698–CNY257,094) in 2022 Chinese Yuan. Results The incremental cost effectiveness ratio (ICER) of ICD therapy compared to no ICD therapy is 139,652 CNY/QALY, which is about 1–2 times China’s GDP per capita. The probability that ICD therapy is cost effective was 92.1%. Results from sensitivity analysis supported the findings of the base case. Conclusions ICD therapy compared to no ICD therapy is cost-effective for the 1.5PP patients in China.

Effect of implantable cardioverter-defibrillator in non-ischaemic systolic heart failure according to the Heart Failure Collaboratory Medical Therapy Score: extended follow-up of the DANISH trial

Abstract Background The Heart Failure Collaboratory (HFC) has developed a medical therapy score which integrates types and doses of guideline-directed pharmacotherapies in patients with systolic heart failure, providing a measure of treatment quality. In clinical trials, this score may help determine the additive effect of new treatments. In the Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators (ICDs) in Patients with Non-ischaemic Systolic Heart Failure on Mortality (DANISH) trial, ICD implantation did not provide an overall survival benefit in patients with non-ischaemic systolic heart failure. Purpose Adding four years of additional follow-up to the DANISH trial, we examined the effect of ICD implantation according to baseline modified HFC (mHFC) medical therapy score. Methods In the DANISH trial, 1,116 patients with non-ischaemic systolic heart failure were randomised to receive an ICD (N = 556) or usual clinical care (N = 560, control group). The primary outcome was death from any cause. In the mHFC score, patients were assigned a score for each drug class of the original cornerstones of systolic heart failure treatment (renin-angiotensin-system inhibitor, beta-blocker, and mineralocorticoid receptor antagonist). The maximum score was 100%, corresponding to optimal medical therapy with all three types of medication (=&amp;gt;50% of target dose). Results The median mHFC score at baseline was 67% (25th-75th percentile, 67%-100%; range, 17%-100%). During a median follow-up of 9.5 years, the ICD group did not have significantly lower all-cause mortality compared with the control group (hazard ratio [HR] 0.89 [95% CI, 0.74-1.08]). The results were independent of the mHFC score at baseline (mHFC score = &amp;lt; median: HR 0.91 [95% CI, 0.70-1.19]; mHFC score &amp;gt; median: HR 0.87 [95% CI, 0.66-1.14]; P for interaction, 0.94). Similarly, ICD implantation did not reduce the rate of cardiovascular death overall (HR 0.87 [95% CI, 0.70-1.09]), and this association was not modified by the mHFC score (mHFC score = &amp;lt; median: HR 0.90 [95% CI, 0.65-1.24]; mHFC score &amp;gt; median: HR 0.84 [95% CI, 0.61-1.15]; P for interaction, 0.89). The ICD group had a significantly lower rate of sudden cardiovascular death in the overall population (HR, 0.60 [95% CI, 0.40-0.92]), and this association was not modified by the mHFC score (mHFC score = &amp;lt; median: HR 0.72 [95% CI, 0.40-1.29]; mHFC score &amp;gt; median: HR 0.53 [95% CI, 0.28-0.99]; P for interaction, 0.59). See Figure for results. Conclusions In this extended follow-up study of the DANISH trial, ICD implantation did not provide an overall survival benefit in patients with non-ischaemic systolic heart failure regardless of baseline medical heart failure therapy, assessed by the mHFC score.Modified HFC score in the DANISH trial

Effectiveness of implantable cardioverter defibrillator as primary prevention in hypertrophic cardiomyopathy: One year follow-up study

Effectiveness of implantable cardioverter defibrillator as primary prevention in hypertrophic cardiomyopathy: One year follow-up study

Imaging modality for left ventricular ejection fraction estimation and effect of implantable cardioverter-defibrillator on mortality in patients with heart failure

Implantable cardioverter-defibrillators (ICDs) improve outcomes in patients with heart failure (HF) with left ventricular ejection fraction (LVEF) ≤35%. Less is known about whether outcomes varied between the 2 noninvasive imaging modalities used to estimate LVEF-2-dimensional echocardiography (2DE) and multigated acquisition radionuclide ventriculography (MUGA)-which use different principles (geometric vs count-based, respectively). The purpose of this study was to examine whether the effect of ICD on mortality in patients with HF and LVEF ≤35% varied on the basis of LVEF measured by 2DE or MUGA. Of the 2521 patients with HF with LVEF ≤35% in the Sudden Cardiac Death in Heart Failure Trial, 1676 were randomized to either placebo or ICD, of whom 1386 had LVEF measured by 2DE (n = 971) or MUGA (n = 415). Hazard ratios (HRs) and 97.5% confidence intervals (CIs) for mortality associated with ICD use were estimated overall, checking for interaction, and within the 2 imaging subgroups. Of the 1386 patients in the present analysis, all-cause mortality occurred in 23.1% (160 of 692) and 29.7% (206 of 694) of patients randomized to ICD or placebo, respectively (HR 0.77; 97.5% CI 0.61-0.97), which is consistent with that in 1676 patients in the original report. HRs (97.5% CIs) for all-cause mortality in the 2DE and MUGA subgroups were 0.79 (0.60-1.04) and 0.72 (0.46-1.11), respectively (P = .693 for interaction). Similar associations were observed for cardiac and arrhythmic mortalities. We found no evidence that in patients with HF and LVEF ≤35%, the effect of ICD on mortality varied by the noninvasive imaging method used to measure LVEF.

Abstract 15666: Survival Benefit of Implantable Cardioverter Defibrillators in Patients With Catecholaminergic Polymorphic Ventricular Tachycardia

Introduction: The effectiveness of implantable cardioverter-defibrillators (ICDs) in reducing mortality in patients with Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is debated.Hypothesis. The ICD confers survival benefit in patients with CPVT. Methods: We included n=238 genotype-proven CPVT patients, of whom 91 (38%) had an ICD implanted. All patients were treated with beta-blocker (BB) monotherapy. Survival probability at the occurrence of a first Life-threatening Arrhythmic Event (LAE, defined as: sudden cardiac death, aborted cardiac arrest or hemodynamically non-tolerated ventricular tachycardia) was compared between ICD carriers and non-ICD carriers. In ICD carriers, the benefit-to-harm ratio (rate of appropriate shocks on LAE over rate of major complications) was investigated. Results: During 1,643 person-years of follow-up, 35/238 (15%) patients experienced a first LAE on BB monotherapy (annual LAE rate 2.1%, 95%CI: 1.5-3.0%). Of the 35 individuals who experienced an LAE, 23 patients had an ICD when the LAE occurred, and all survived after ICD shock. Of the remaining 12 patients who were not carriers of an ICD, 4/12 (33%) died suddenly, 2/12 (17%) survived but suffered anoxic brain injury, while 6/12 (50%) survived without consequences. The probability of dying at the occurrence of a first LAE was 25-fold higher (OR: 24.9, 95% CI: 1.2-513.0; p=0.037) in patients without an ICD, as compared to patients with an ICD. Major complications occurred in 17/91 (19%) patients with an ICD (2.6% per year, 95%CI: 1.5%-4.1%). Comparing the rate of major complication to the rate of appropriate ICD shocks on LAE (LAE rate 5.2% per year, 95%CI: 3.5-7.4%), the benefit-to-harm ratio was 2, favoring the benefit of ICD therapy. Conclusion: The ICD conferred a significant survival benefit in terms of arrhythmic mortality at the occurrence of the first LAE in BB monotherapy.

Health-Related Quality of Life in the Spironolactone to Reduce ICD Therapy (SPIRIT) Trial.

To describe health related quality of life (HRQOL) and symptoms in the SPIRIT trial and determine effects of implantable cardioverter defibrillator (ICD) shocks on HRQOL over 24 months. Ninety participants aged 66 ± 10 years, 96% men, 75% with NYHA class II, with an ICD were randomized to spironolactone 25 mg (N = 44) or placebo (N = 46). HRQOL was measured every 6 months for 24 months using: Patient Concerns Assessment (PCA), Short Form Health Survey-Veterans Version (SF-36V), and Kansas City Cardiomyopathy Questionnaire (KCCQ). Linear mixed modeling compared changes in HRQOL over-time and ANCOVA compared HRQOL between those getting an ICD shock or not. Over 24-months, there were no differences in HRQOL between the spironolactone versus placebo groups. Those with at least one ICD shock reported significantly lower HRQOL and more symptoms at 6- and 24-months. Patients receiving one or more ICD shocks reported significant reductions in HRQOL and higher symptoms.

Deactivation of implantable cardioverter defibrillator in Japanese patients with end-stage heart failure.

BackgroundDespite the effectiveness of implantable cardioverter defibrillators (ICDs) in the prevention of sudden cardiac death, shock therapy causes patients to experience pain and psychological distress, which contradicts the purpose of palliative care. It is difficult to predict the time course for heart failure (HF) patients, unlike that for cancer patients. The aim of this study was to evaluate the deactivation status of ICD therapy in Japanese patients with end‐stage HF.MethodsWe retrospectively studied 51 ICD patients who died due to worsening HF at Tokyo Women's Medical University Hospital from 2010 to 2019. The frequency of ICD therapy delivered before death and information about the discussion of deactivation and do not attempt resuscitation (DNAR) decisions were reviewed using medical charts.ResultsOf 51 patients, 12 (24%) patients deactivated ICD therapy and seven patients underwent deactivation within 24 hours of a DNAR order. The median time from deactivation to death was 3 days (range, 0‐56). Of 39 patients with DNAR orders, 27 (69%) did not undergo deactivation. A relatively high proportion of patients (n = 14, 27%) experienced ICD shocks within 1 month of death. The frequency of electrical storms within 1 month of death was also high (n = 12, 24%).ConclusionsOur study showed that only one‐fourth of Japanese patients with end‐stage HF underwent deactivation of ICD therapy. A relatively high frequency of shock therapy was observed in the last month before death.

Out-of-hospital cardiac arrest patients with implantable cardioverter-defibrillators: What are their outcomes?

The aim of the studyTo identify the prognostic factors and effects of implantable cardioverter-defibrillators (ICDs) in out-of-hospital cardiac arrest (OHCA) patients with ICDs because the clinical characteristics and outcomes of OHCA patients with ICDs are unknown. MethodsThe North American Resuscitation Outcomes Consortium (ROC) Cardiac Epistry Version 3 dataset was analyzed. Eligible patients were divided into OHCA patients with and without ICDs. Multivariable regressions were employed to analyze. ResultsOf 51,634 eligible OHCA patients, 581 (1.13%) had implanted ICDs. Among them, 53 (9.1%) patients survived to hospital discharge, and 40 (6.9%) patients had favorable neurological outcome at hospital discharge. Multivariable regression showed ICDs were not associated with OHCA outcomes in the total OHCA patients. In the OHCA patients with ICDs, shockable initial emergency medical services (EMS)-recorded rhythms and the ICD-shock-only defibrillation pattern were independent favorable factors for survival to hospital discharge(OR = 3.3, 95%CI 1.7–6.2, P < 0.001; OR = 2.4, 95%CI 1.1–5.5, P = 0.035, respectively) and neurological outcome at hospital discharge (OR = 6.5, 95%CI 2.9–14.4, P < 0.001; OR = 3.6, 95%CI 1.4–9.1, P = 0.006, respectively). During field resuscitation in OHCA patients with ICDs, at least 34.9% of total patients and 64.6% of patients with initial EMS-recorded VT/VF rhythms needed additional external shocks. ConclusionsShockable initial EMS-recorded rhythms and ICD-shock-only defibrillation pattern were independent factors for the favorable outcomes of OHCA patients with ICDs. ICDs were not associated with the outcomes of OHCA, and additional external shocks were needed in a substantial number of OHCA patients with ICDs during field resuscitation.

P1464A question of gender equality. Sex-related differences in survival after primary prevention implantable cardioverter-defibrillator implantation for dilated cardiomyopathy An analysis from POLKARD

Abstract OnBehalf POLKARD Polish ICD Registry Background The protective effects of implantable cardioverter defibrillators (ICDs) in the primary prevention of sudden cardiac death of patients presenting with left ventricular (LV) systolic dysfunction are unequivocal. Nevertheless, female underrepresentation has been a consistent finding in all randomized controlled primary prevention ICD trials. Surprisingly, there is a vast body of literature on female primary prevention ICD patients exhibit a lower overall mortality. Purpose Therefore, we analyzed data from a large, nationwide POLKARD registry to evaluate the effect of sex on survival after primary prevention cardioverter-defibrillator implantation for dilated cardiomyopathy. Methods All patients enrolled in the Polish ICD Registry from 2008 to 2014 were identified. Patients were included in the study if they were designated as receiving an ICD for primary prevention of SCD after documented non-ischeamic cardiomyopathy. Kaplan-Meier survival analysis was used to assess all-cause mortality. Results Of the 964 ICD recipients, 241 (25%) were women (mean age of 64± 0,45 years). During a mean follow-up of 5,53 ± 2,48 years 32% of women and 42% of men died. Kaplan-Meier curve depicted a significantly lower mortality for women than for men (p = 0,05). The median survival time was 6,73 years (55 deaths per 1000 person-years) versus 6,37 years (78 deaths per 1000 person-years) for women and men, respectively. Conclusions In agreement with previous studies, our data indicate that primary prevention implantation rates for dilated cardiomyopathy are lower in women. However, the reasons are not entirely understood.

Validity Evidence of the Brazilian Version of the Florida Shock Anxiety Scale for Patients with Implantable Cardioverter Defibrillators.

ResumoFundamento A despeito da comprovada efetividade do cardioversor-desfibrilador implantável (CDI), as terapias de choque deflagradas pelo dispositivo podem causar níveis elevados de ansiedade e depressão, provocando efeitos deletérios na qualidade de vida.Objetivo Realizar a tradução, adaptação transcultural e validação do instrumento Florida Shock Anxiety Scale (FSAS) para a língua portuguesa falada no Brasil.Métodos Nesse estudo psicométrico, a validade de construto foi realizada pela análise fatorial exploratória (AFE) e confirmatória (AFC) e pela Teoria de Resposta ao Item. Os índices de ajustamento da AFC foram: Robust Mean-Scaled Chi Square/df NNFI, CFI (Comparative Fit Index), GFI (Goodness Fit Index), AGFI (Adjusted Goodness Fit Index), RMSEA (Root Mean Square Error of Approximation) e RMSR (Root Mean Square of Residuals). A confiabilidade foi verificada pelo Alfa de Cronbach, Ômega de McDonald e Greatest Lower Bound. As análises foram realizadas no SPSS 23.0 e Factor 10.8.01, com nível de significância de 5%.Resultados A versão final em português do FSAS foi administrada em 151 portadores de CDI, com idade média de 55,7 ± 14,1 anos e predomínio do sexo masculino. A análise paralela indicou que o FSAS é unidimensional, com variância explicada de 64,4%. As correlações variaram de 0,31 a 0,77; as cargas fatoriais de 0,67 a 0,86 e as comunalidades de 0,46 a 0,74. Os índices de ajustamento da AFC estabeleceram-se acima dos limites de qualidade. Encontramos evidências satisfatórias de confiabilidade da escala FSAS.Conclusão O instrumento FSAS-Br apresentou evidências consistentes de validade e confiabilidade, podendo, portanto, ser utilizado em portadores de CDI do Brasil. (Arq Bras Cardiol. 2020; 114(5):764-772)

Does sympathetic hyperactivity adversely impact on the effect of implantable cardioverter-defibrillator in patients with diabetes and non-ischaemic systolic heart failure?

Does sympathetic hyperactivity adversely impact on the effect of implantable cardioverter-defibrillator in patients with diabetes and non-ischaemic systolic heart failure?

P4533Duration of heart failure and effect of defibrillator implantation in patients with non-ischemic systolic heart failure

Abstract Introduction Patients with non-ischemic systolic heart failure have increased risk of sudden cardiac death (SCD) and death from progressive pump failure. Whether the risk of SCD changes over time is unknown. We seek to investigate the relationship between duration of heart failure, mode of death, and effect of implantable cardioverter defibrillator (ICD) implantation. Methods We examined the risk of all-cause death and SCD according to the duration of heart failure among patients with non-ischemic systolic heart failure enrolled in the Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH) trial. Patients were divided according to quartiles of heart failure duration (Q1 ≤8 months, Q2 9 ≤18 months, Q3 19 ≤65 months, Q4 ≥66 months). Results A total number of 1116 patients were included. Patients with the longest duration of heart failure were older, more often men, had more comorbidity, and more often received cardiac resynchronizing therapy device. Doubling of heart failure duration was an independent predictor of both all-cause mortality (HR 1.26 95% CI 1.17–1.37, p&lt;0.0001), and SCD (HR 1.29 95% CI 1.11–1.49, p=0.0009). The proportion of deaths caused by SCD was not different between heart failure quartiles (p=0.91), and the effect of ICD implantation on all-cause mortality was not modified by the duration of heart failure (p=0.59). Duration of heart failure and death Conclusions Duration of heart failure predicted both all-cause mortality and risk of SCD independently of other risk indicators. However, the proportion of death caused by SCD did not change with longer duration of heart failure and the effect of ICD was not modified by the duration of heart failure. Acknowledgement/Funding The work was sponsored by The Danish Heart Foundation (Hjerteforeningen) and the Lundbeck Foundation (Lundbeckfonden). The DANISH trial was supported

Implantable Cardioverter Defibrillators in Patients With Continuous Flow Left Ventricular Assist Devices: Utilization Patterns, Related Procedures, and Complications.

BackgroundThe effect of implantable cardioverter defibrillators (ICD) in patients with continuous flow left ventricular assist devices (LVADs) on outcomes has not been evaluated in a randomized clinical trial.Methods and ResultsThis is a retrospective single‐center study that included patients who underwent continuous flow LVAD implantation at the Cleveland Clinic between October 2004 and March 2017. Patients were evaluated according to the presence or absence of ICD at the time of LVAD insertion. Among 486 patients in the study cohort, 387 (79.6%) had an ICD before LVAD insertion. Patients with ICD before LVAD were older and had lower use of pre‐LVAD inotropes, extracorporeal membrane oxygenation, and mechanical ventilation. There were 81 patients (21.4% of patients with ICD) who required 93 procedures after LVAD: 74 generator exchanges, 12 lead revisions, and 7 complete system removals because of infection. Of the 99 patients without ICD, 52 (53%) underwent ICD implantation: 29 for primary prevention and 23 for secondary prevention. Patients were followed for a median of 401 (interquartile range 150–966) days. The presence of a pre‐LVAD ICD was not associated with mortality in a multivariable model (hazard ratio 1.19, 95% CI 0.73–1.93, P=0.492), nor was the presence of an ICD at any point when analyzed as a time‐varying covariate (hazard ratio 1.05, 95% CI 0.50–2.20, P=0.907).ConclusionsThere is no apparent mortality benefit associated with an ICD in a contemporary cohort of patients with continuous flow LVADs to balance considerable morbidity involving ICD‐related procedures and complications.

Sex Differences in Advanced Heart Failure Therapies.

This in-depth review of sex differences in advanced heart failure therapy summarizes the existing literature on implantable cardioverter defibrillators, biventricular pacemakers, mechanical circulatory support, and transplantation with a focus on utilization, efficacy/clinical effectiveness, adverse events, and controversies. One will learn about the controversies regarding efficacy/clinical effectiveness of implantable cardioverter defibrillators and understand why these devices should be implanted in women even if there are sex differences in appropriate shocks. Individuals will learn about the sex differences with biventricular pacemakers with respect to ventricular remodeling and reduction in heart failure hospitalizations/mortality, as well as, possible mechanisms. We will demonstrate sex differences in heart transplantation and waitlist survival. Despite similar survival for women and men with left ventricular assist devices, there are sex differences in adverse events. These devices do successfully bridge women and men to transplant, yet women are less likely than men to have a left ventricular assist at time of listing and time of transplantation. Finally, one will learn about the concerns regarding poor outcome for men who receive female donor hearts and discover this may not be due to sex, but rather size. More research is needed to better understand sex differences and further improve advanced heart failure therapy for both women and men.

Efficacy of an implantable cardioverter-defibrillator in patients with diabetes and heart failure and reduced ejection fraction

BackgroundThe effect of implantable cardioverter-defibrillator (ICD) therapy in patients with heart failure with reduced ejection fraction (HFrEF) and diabetes is not fully elucidated.MethodsWe examined the effect of ICD therapy on sudden cardiac death, cardiovascular death and all-cause mortality, according to diabetes status at baseline in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). The outcomes were analyzed by use of cumulative incidence curves and Cox regressions models.ResultsOf the 1676 patients randomized to an ICD or placebo, 540 (32%) had diabetes at baseline. Patients with diabetes were slightly older (61 vs 58 years) and were more often in NYHA class III (37% vs 28%). ICD therapy did not reduce the risk of sudden cardiac death in HFrEF patients with diabetes (HR = 0.85; 95% CI 0.52–1.40); even though these patients had a higher risk of sudden cardiac death compared to patients without diabetes (HR = 1.73 95% CI 1.22–2.47). By contrast, ICD therapy did reduce sudden cardiac death in HFrEF patients without diabetes (HR = 0.26; 95% CI 0.15–0.46); Pinteraction=0.002. The findings for cardiovascular and all-cause death were similar.ConclusionICD therapy did not reduce the risk of sudden cardiac death (or, as a consequence, all-cause death) in HFrEF patients with diabetes. Conversely, an ICD reduced the risk of sudden death in patients without diabetes, irrespective of etiology.

Abstract 122: Comparative Effectiveness of Primary Prevention Implantable Cardioverter-Defibrillators in Older Adults With Diabetes Mellitus: Insights From the Get With the Guidelines - Heart Failure Registry

Introduction: Patients with diabetes mellitus (DM) and heart failure with reduced ejection fraction (HFrEF) are at increased risk of sudden death. However, given the burden of competing causes of death in patients with DM, therapies to reduce the risk of sudden death may have reduced efficacy. We aimed to assess the effectiveness of implantable cardioverter-defibrillators (ICDs) in a large US registry. Methods: We linked data from the GWTG-HF registry to the Centers for Medicare/Medicaid Services claims (January 2010 to December 2014). Using Cox proportional hazard models with propensity score matching for baseline covariates, among patients with and without DM, we compared patients who received an ICD (or were prescribed an ICD at discharge) to those without an ICD. The primary outcome was all-cause mortality. Results: Among the 17,186 patients in our study cohort, 6683 (38%) had DM. For patients with DM, those with an ICD (n=663), compared to those without and ICD, were younger (74.0 vs. 78.0 years of age), more likely to be male (66.3% vs. 55.7%) and more likely to have coronary disease (67.8% vs. 60.4%) Similar trends were seen among patients without DM (n=1,031). Among patients with DM, in matched cohorts, an ICD was associated with a reduced risk of mortality (54.4% vs. 60.0%; adjusted HR [aHR] 0.74, 95% CI 0.65-0.83; figure panel A). Similar results for mortality were seen in patients without DM (47.4% vs. 57.0%; aHR 0.68, 95% CI 0.61-0.75; figure panel B). Diabetes did not modify the relationship between ICD and mortality (interaction p-value = 0.24). Conclusion: Among patients with HFrEF, primary prevention ICD was associated with reduced mortality in patients with and without diabetes. These findings support current guideline recommendation for primary prevention ICDs among eligible patients with DM.

Remote monitoring and inappropriate therapies in ICD patients: The THORN registry

Inappropriate shocks (IS) are a major side effect of implantable cardioverter defibrillators (ICD). Remote monitoring (RM) may reduce inappropriate diagnoses (ID) and subsequent inappropriate therapies (IT). The purpose of THORN study was to determine the ability of ICD RM to early identify ID of ventricular arrhythmias and prompt physician reaction, in order to reduce the risk of recurrent IT. THORN is an observational multicenter study of RM ICD patients, separated in a retrospective cohort (R), issued from a large RM database collected since 2007 by Biotronik SE & Co.KG and a prospective cohort (P) of patients implanted since 2012. The primary objective was to determine: 1/in the retrospective cohort, the relative proportion of patients experiencing at least one IT during a 15-month follow-up period, and, 2/in the prospective cohort, the medical reaction time (MRT) and ID recurrence after an initial ID. A total of 1891 patients (R: 1379, P: 512), implanted with a CRT-D (28.1%) or conventional ICD, (single chamber: 45.1%; dual chamber: 26.8%) were enrolled (83.6% men, 62.9 ± 12.8 y), 31.8% in primary prevention. During 13.7 ± 3.5 months of follow-up, 8.6% (R: 9.2%, P: 6.9%, P = 0.05) of the patients experienced at least one ID, of whom, 75.3% suffered at least one IT (R: 74%, P: 80%, P = NS) and 35.8% at least one IS. The median MRT was 9 days (0 to 145 days). It was 4 times longer for ID due to supraventricular tachyarrhythmias (16 days) compared to those due to abnormal sensing (4 days) ( P = 0.04). ID recurrence occurred in 37% of ID patients, with a substantial part (25.7%) within the MRT. Among the 6.5% of patients experiencing at least one IT, 36.1% had an IT recurrence. The rate of patients experiencing ID/IT and recurrences seems to decrease over time. Though RM is intended to take action earlier, the MRT is sometimes long and could be reduced as ID/IT recurrences are not infrequent within the MRT period.

Defibrillator shocks and their effect on objective and subjective patient outcomes: Results of the PainFree SST clinical trial

The effect of implantable cardioverter-defibrillator (ICD) shock on device-measured activity and patient-reported outcomes is unknown. The purpose of this study was to analyze the acute and long-term effects of ICD shock on objective behavioral data (ie, device-based physical activity) and subjective patient-reported outcomes (eg, quality of life and shock anxiety). The PainFree Smart Shock Technology (SST) clinical trial included 2770 patients with a single- or dual-chamber ICD or cardiac resynchronization therapy - defibrillator device who were followed for 22 ± 9 months. Participants completed measures of quality of life (EuroQol-5D [EQ-5D] questionnaire) and shock anxiety (Florida Shock Anxiety Scale) at baseline, biannual visits, and monthly for 6 months after an ICD shock. Daily physical activity data were obtained from a built-in device accelerometer. The average daily activity was 185.3 ± 119.4 min/d. Activity was significantly reduced after an ICD shock (P < .0001) and recovered to a normal level after ∼90 days. An ICD shock was also associated with decreased quality of life (EQ5-D health score) and increased EQ-5D anxiety scores, but it did not affect mobility, self-care, activity, or pain. Similarly, shock anxiety (Florida Shock Anxiety Scale) increased in shocked patients and remained significantly elevated at 24 months, regardless of appropriate or inappropriate shock delivery. ICD shocks have a long-lasting adverse effect on both objective, device-measured physical activity and subjective patient-reported outcomes of quality of life and shock anxiety. Successful management of patients with an ICD requires attention to clinically relevant behavioral and psychological outcomes to expedite recovery and return to activities of daily living.

Implantablecardioverter-defibrillator in the elderly: Predictors of appropriate interventions and mortality at 12-month follow-up.

The effectiveness of implantable cardioverter-defibrillator (ICD) in the elderly is uncertain, given their competing risk of nonarrhythmic death. Guidelines state that an ICD should be implanted if the expectation of survival is at least 1 year. However, survival is not easy to predict in elderly patients with severe cardiac disease. To assess 12-month survival after ICD implantation in patients aged ≥75 years, to identify predictors of 12-month mortality, and to evaluate the incidence of ICD therapy during follow-up. We retrospectively analyzed all clinical, instrumental, and survival data of patients ≥75 years old who received an ICD in our center from 2000 to 2013. We included 127 patients (mean age 78 years). ICD was implanted for primary prevention in 61%. The 12-month survival rate was 87.4%. At both univariate and multivariate analyses, left ventricular ejection fraction (EF) ≤ 25%, and moderate to severe impaired renal function (IRF) independently predicted 12-month mortality that was as high as 45.5% in patients with both risk factors. During a median follow-up of 38 months, 30 patients (23.6%) received ≥1 appropriate ICD interventions, but only 3.1% of shocks occurred during the first year, and none in the subgroup of patients with EF ≤ 25% and IRF. Twelve-month survival in elderly patients after ICD implantation is good and the indication for ICD should not be based on age alone. However, the subgroup with EF ≤ 25% and IRF showed a high 12-month nonarrhythmic mortality and did not benefit from ICD implantation.