Implantable Cardioverter-defibrillator Group Research Articles

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

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

The impact of implantable cardioverter-defibrillator implantation on health-related quality of life in the DANISH trial.

The Danish Study to Assess the Efficacy of Implantable Cardioverter-Defibrillators (ICD) in Patients with Non-ischaemic Systolic Heart Failure (HF) on Mortality (DANISH) found no overall effect on all-cause mortality. The effect of ICD implantation on health-related quality of life (HRQoL) remains to be established as previous trials have demonstrated conflicting results. We investigated the impact of ICD implantation on HRQoL in patients with non-ischaemic systolic HF, a prespecified secondary endpoint in DANISH. In DANISH, a total of 1116 patients with non-ischaemic systolic HF were randomly assigned (1:1) to ICD implantation or usual clinical care (control). Patients completed disease-specific HRQoL as assessed by Minnesota Living with Heart Failure Questionnaire (MLHFQ; 0-105, high indicating worse). Changes in HRQoL 8 months after randomization were assessed with a mixed-effects model. At randomization, MLHFQ was completed by 935 (84%) patients (n = 472 in the ICD group and n = 463 in the control group) and was reassessed in 274 (58%) and 292 (63%) patients, respectively after 8 months for the primary analysis. Patients in the ICD group vs. the control group had similar improvements in MLHFQ after 8 months [least square mean -7.0 vs. -4.2 (P = 0.13)]. A clinically relevant improvement (decrease ≥5) in the MLHFQ overall score at 8 months was observed in 151 patients in the ICD group and 148 patients in the control group [55% vs. 51%, respectively (P = 0.25)]. Implantable cardioverter-defibrillator implantation in patients with non-ischaemic systolic HF did not significantly alter HRQoL compared with patients randomized to usual clinical care.

Clinical profile, complications, and quality of life in patients undergoing automatic implantable cardioverter-defibrillator implantation in a tertiary care hospital of North India

Background: Despite better understanding of various aspects of Sudden Cardiac Death (SCD), mortality from the disease still remains very high. Coronary artery disease (CAD) is the most common cause of SCD in all parts of India. The American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society (ACC/AHA/HRS) guidelines recommend the use of implantable cardioverter-defibrillator (ICD) therapy as a primary prevention. Aim: The aim of our study was to assess the clinical and demographic profile, complications and quality of life (QOL) of patients undergoing ICD implantation as compared to controls at a tertiary care center of north India. Method: A total of 64 patients with mean age 54.39± 11.54 years were implanted ICD during a period of one year. During the same period, 51 patients in which ICD could not be implanted due to financial reasons were included as controls. Of the 64 patients, 43 (67.19%) patients received ICD for primary prevention whereas 21 (32.81%) patients received it for secondary prevention. Result: At a follow up of 6 months, mortality was 4 (7.84%) in ICD group as compared to 8 (15.69%) in control group. Mortality from SCD in ICD and control group was 2 and 5 respectively (P = 0.23). ICD interrogation data was collected for 37 cases of which 19 (51.35%) patients had records of ventricular tachycardia (VT) and 3 (8.1%) patients had records of ventricular fibrillation (VF) respectively. Total VT/VF episodes recorded in primary prevention group were 10, whereas 12 in secondary prevention group. Success rate of ATP and ICD shocks were 30.23% and 95.92% respectively. All 47 VT/VF episodes were terminated by shocks. Conclusion: The QOL of patients undergoing ICD implant was better in the domains of social relationship and environment though the difference was not significant statistically. Overall, there was a significant reduction in SCD mortality and no deterioration in QOL.

Implantable cardioverter defibrillator - powerful weapon in primary and secondary prevention of sudden cardiac death

Bacgraund/Aim. Sudden cardiac death (SCD) is one of the biggest problems of the contemporary medicine. Large studies showed that anti-arrhythmics, including amiodarone, are not effective in prevention of SCD in the patients with cardiac diseases who were on drug treatment. Those patients who received implantable cardioverter defibrillators (ICD) had better survival. The aim of this paper was to determine whether the patients receiving the ICD in the primary and secondary SCD prevention have longer survival than the patients treated exclusively with drug therapy. Methods. We included 1,260 patients with cardiac insufficiency and reduced left ventricular ejection fraction (LVEF < 35%) who were at high risk for malignant ventricular arrhythmias and SCD. Five hundred forty patients received ICD therapy. The cardiac resynchronization therapy ? CRT/ICD group (n = 270) comprised the patients with cardiac insufficiency and CRT/ICD pacemaker at an optimal medical therapy. In the control group (n = 450), there were the patients with cardiac insufficiency (NYHA functional class 3?4, LVEF ? 35%, QRS duration ? 130 ms), at optimum drug therapy. Results. In the ICD group, there was a statistically significant increase in end-systolic volume (ESV) from 92.68 mL to 99.05 mL. In the group of patients with cardiac insufficiency who were on drug therapy, there was a significant decrease in LVEF (33.15% vs. 30.2%; p = 0.017), 6-minute walk distance (6 MWT distance) (216.55 m vs. 203.27 m, p = 0.003). In the same group, there was an increase in the values of ESV (90.19 mL vs. 95.41 mL; p = 0.011). An increase in the mortality rate in the group of patients with drug therapy compared to the CRT/ICD and ICD groups was statistically significant (p < 0.05). Conclusions. An ICD pacemaker implantation significantly reduces mortality compared to medical therapy only. In addition, the patients who have CRT in addition to ICD pacemaker, have a significantly better quality of life and increase in LVEF.

Abstract 17303: Permanent Cardiac Pacemaker Implant Improves Sleep Habit

Background: Permanent cardiac pacemaker is indicated in patients with symptomatic bradycardia. Its role in sleep disorder is unknown, however some patient report improvement in their sleep habit after permanent cardiac pacemaker implant. We examined the role of permanent cardiac pacemaker in relation to patients’ sleeping habits. Methods: Total of 174 patients who agreed to participate in the study were included (21 Implantable Cardioverter Defibrillator (ICD) and 153 pacemaker implants). The ICD group was used as the control group. Patients with bi-ventricular pacemaker implants for cardiac re-synchronization therapy were excluded from the study. Questionnaires about the sleep habit were evaluated before and after the device implant and analyzed using paired T test and Chi square test. Results: The indications for permanent pacemaker therapy were high grade AV block (33%), sick sinus syndrome (64%) and syncope (1%). Indications of ICD were primary or secondary sudden cardiac death prevention without history of known symptomatic bradycardia (100%). Mean Ventricular pacing was 40.39% (interquartile range: 97%) of the time in the pacemaker group. There were no baseline differences in sleep duration and quality of sleep in both the ICD and pacemaker group prior to device implant. Improved sleep habit (46% in pacemaker vs 23% in the ICD group, P=0.04) and better quality of sleep (44% in pacemaker vs 19% in ICD, P=0.01) were reported after device implant. The patients in pacemaker group reported much improvement in sleep duration (average by 30 minutes in Pacemaker vs 15 minutes in ICD, P=0.002). Conclusions: Patients who had permanent pacemaker implant for symptomatic bradycardia showed improved sleep quality and duration than the patients with ICD implant for primary or secondary sudden cardiac death prevention. Mechanisms of improved sleep habit in pacemaker group are unclear, but possibly associated with improved cardiac output with consistent heat rate during sleep from the pacemaker. Further large-scale studies are needed to validate this concept.

Implantable Cardioverter Defibrillators in Patients with Continuous Flow Left Ventricular Assist Devices: Utilization Patterns, Shock Therapies and Complications.

Background The use of implantable cardioverter defibrillators (ICDs) in patients with continuous flow left ventricular assist devices (LVADs) has not been evaluated in randomized clinical trials and the observational data published so far is controversial. To our knowledge, the burden of ICD related procedures after LVAD has not been previously described. Methods This 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 grouped according to the presence or absence of ICD at the time of LVAD insertion. Outcomes after LVAD insertion were assessed including revisions of existing and subsequent implantation of ICDs. Results There were 486 patients in the study cohort; of those, 387 (79.6%) had an ICD prior to LVAD insertion. Patients with ICD prior to LVAD were older and had lower use of inotropes, extracorporeal membrane oxygenation, and mechanical ventilation before LVAD. There were 4 patients with leads cut or removed during LVAD, and 12 that had post-operative lead dysfunction due to dislodgment. There were 80 patients (21% of patients with ICD) who required 96 procedures after LVAD: 74 generator exchanges because of end of life or technical failure, 15 lead revisions, and 7 complete system removals because of infection. Of the 99 patients without ICD, 52 underwent ICD implantation: 38 for primary prevention and 14 for secondary prevention. Of those 4, had additional procedures: 2 generator changes due to end of life, 1 lead revision, and 1 system extraction due to pseudomonas endocarditis. The median follow ICD data follow up was 227 days in the pre-LVAD ICD group and 390 days in the post LVAD ICD group. There were 115(30%) and 13 (25%) patients that experimented ICD shocks in the pre-LVAD and post-LVAD ICD groups respectively. In both groups approximately 80% were categorized as appropriate.The unadjusted 30-day mortality was 5.2% and 10.1% in patients with and without ICD respectively (p=0.097). Conclusion In this cohort, ICD related procedures are common in patients with continuous flow LVADs and occur in about 1/5th of patients. During LVAD implantation displacement or cut of the ICD lead because of tricuspid valve intervention is not infrequent. More than half of patients without an ICD at baseline had an ICD implanted after LVAD. A substantial proportion of patients experience ICD shocks. The impact of shocks in outcomes remains to be determined.

Implantable cardioverter-defibrillator in Chagas heart disease: A systematic review and meta-analysis of observational studies

BackgroundIn patients with Chagas cardiomyopathy (ChCM), sudden cardiac death (SCD) is the leading cause of mortality. Implantable cardioverter-defibrillator (ICD) is a well-established therapy for secondary prevention in patients with structural heart disease, but there are conflicting opinions regarding its efficacy and safety in patients with ChCM. The aim of this meta-analysis was to assess the efficacy of the ICD for secondary prevention in patients with ChCM, comparing mortality as the primary outcome of patients treated with ICD with those treated with amiodarone. MethodsWe systematically searched five databases for studies assessing mortality outcomes in patients with ChCM and sustained ventricular tachycardia (VT) treated with ICD implantation or with amiodarone. The results of studies were pooled using random-effects modeling. ResultsThere was no randomized clinical trial comparing efficacy of ICD versus medical treatment in patients with ChCM. Six observational studies were included, totalizing 115 patients in amiodarone group and 483 patients in ICD group. The mortality outcome in the ICD population was 9.7 per 100 patient-years of follow-up (95%CI 5.7–13.7) and 9.6 per 100 patient-years in the amiodarone group (95%CI 6.7–12.4) (p = 0.95). Meta-regression did not show any association with LV ejection fraction (p = 0.32), age (p = 0.44), beta-blocker (p = 0.33) or angiotensin-converting enzyme inhibitors (p = 0.096) usage. ConclusionThe best available evidence derived from small observational studies suggests that ICD therapy in secondary prevention of sudden death (VT or resuscitated SCD) is not associated with lower rate of all-cause mortality in patients with ChCM. Randomized controlled trials are needed to answer this question.

Long-term Outcomes Associated With Implantable Cardioverter Defibrillator in Adults With Chronic Kidney Disease

Chronic kidney disease (CKD) is common in adults with heart failure and is associated with an increased risk of sudden cardiac death. Randomized trials of participants without CKD have demonstrated that implantable cardioverter defibrillators (ICDs) decrease the risk of arrhythmic death in selected patients with reduced left ventricular ejection fraction (LVEF) heart failure. However, whether ICDs improve clinical outcomes in patients with CKD is not well elucidated. To examine the association of primary prevention ICDs with risk of death and hospitalization in a community-based population of potentially ICD-eligible patients who had heart failure with reduced LVEF and CKD. This noninterventional cohort study included adults with heart failure and an LVEF of 40% or less and measures of serum creatinine levels available from January 1, 2005, through December 31, 2012, who were enrolled in 4 Kaiser Permanente health care delivery systems. Chronic kidney disease was defined as an estimated glomerular filtration rate of less than 60 mL/min/1.73 m2. Patients who received and did not receive an ICD were matched (1:3) on CKD status, age, and high-dimensional propensity score to receive an ICD. Follow-up was completed on December 31, 2013. Data were analyzed from 2015 to 2017. Placement of an ICD. All-cause death, hospitalizations due to heart failure, and any-cause hospitalizations. A total of 5877 matched eligible adults with CKD (1556 with an ICD and 4321 without an ICD) were identified (4049 men [68.9%] and 1828 women [31.1%]; mean [SD] age, 72.9 [8.2] years). In models adjusted for demographics, comorbidity, and cardiovascular medication use, no difference was found in all-cause mortality between patients with CKD in the ICD vs non-ICD groups (adjusted hazard ratio, 0.96; 95% CI, 0.87-1.06). However, ICD placement was associated with increased risk of subsequent hospitalization due to heart failure (adjusted relative risk, 1.49; 95% CI, 1.33-1.60) and any-cause hospitalization (adjusted relative risk, 1.25; 95% CI, 1.20-1.30) among patients with CKD. In a large, contemporary, noninterventional study of community-based patients with heart failure and CKD, ICD placement was not significantly associated with improved survival but was associated with increased risk for subsequent hospitalization due to heart failure and all-cause hospitalization. The potential risks and benefits of ICDs should be carefully considered in patients with heart failure and CKD.

The contribution of implantable cardioverter defibrillators to systemic inflammation in heart failure patients

Heart failure (HF) is associated with an increased ‘inflammatory burden’, which is manifested by the elevation of serum levels of some inflammatory mediators such C-reactive protein (CRP), cytokines. In addition, high levels of inflammatory markers in patients with HF have been associated with poor outcomes. Lethal ventricular arrhythmias such as asystole and ventricular fibrillation-tachycardia are common in patients with HF and implantable cardioverter defibrillators (ICDs) are effective in preventing these situations. But like every foreign object in the body, ICDs also cause fibrosis and inflammation. This study aimed to show additional contribution of ICDs to systemic inflammation in patients with HF. This is a single centrer retrospective study included 140 HF patients with and without ICD (group 1 and 2) and 53 healty control subjects (group 3). Three groups were compared with regard to Hs-CRP and Neutrophil / Lymphocyte ratio (NL ratio). In order that acute inflammation did not affect the results, the earliest 6th month laboratory measures after ICD implantation were recorded. There are not significant difference between all groups in terms of age and gender, and among group 1 and 2 in terms of disease history, ejection fraction, heart rate and creatinine. When compared to the three groups according to Hs-CRP and NL ratio, there was a significant difference between the groups (both p

Clinical impact of implantable cardioverter-defibrillator in primary prevention of total mortality in non-ischaemic cardiomyopathy: results from a meta-analysis of prospective randomized clinical trials.

Primary prophylactic implantable cardioverter defibrillators (ICDs) have demonstrated a clear all-cause mortality benefit in patients with ischaemic cardiomyopathy, with less compelling evidence supporting its use in patients with non-ischaemic cardiomyopathy (NICM). We performed a meta-analysis of randomized controlled trials (RCTs) evaluating the role of ICD for reduction in total mortality in NICM patients. An electronic search on PubMed, the Cochrane Library, and EMBASE databases was performed to identify the RCTs evaluating the role of prophylactic ICD placement in NICM patients. Mantel-Haenszel risk ratio (RR) fixed-effects model was used to summarize data across treatment arms. Random-effects model was used if heterogeneity (I2) ≥ 25. Patients with cardiac resynchronization therapy pacemaker (CRT-P) were included in the control group. Six RCTs, with a total of 3128 patients and a mean follow-up period of 48 ± 22 months comparing ICD with medical therapy in NICM were included in this analysis. There was a significant reduction in all-cause mortality in the ICD group compared with the medical therapy group [RR 0.79, 95% confidence interval (95% CI) 0.68-0.92; P = 0.002]. No publication bias was noted. Currently available evidence demonstrates that the use of ICD provides a clear and significant reduction in all-cause mortality among patients with NICM.

Quality of life in patients with implantable cardioverter-defibrillator: systematic review of randomized controlled trials.

Implantable cardioverter-defibrillator (ICD) therapy significantly improves the survival of patients who are at high risk for sudden cardiac death. However, it is unclear whether this survival is accompanied by impairment on quality of life (QoL). This systematic review sought to describe whether ICD therapy, as compared with standard treatment, can have an impact on QoL outcomes. Extensive literature searches were carried out in PubMed, EMBASE, LILACS and Cochrane Library. Eligible studies were randomized controlled trials (RCTs) of ICD versus medical therapy that reported valid and reliable measures of QoL. Included studies were reviewed to determine baseline patient characteristics, mean duration of follow-up, questionnaires used to assess QoL and association between QoL scores and ICD shock therapy. Seven studies, enrolling a total of 5,701 patients, were included in this review. The analyzed trials showed conflicting results about the impact of ICD on QoL outcomes. Among the secondary prevention studies, CIDS reported a clear benefit from ICD and AVID showed no difference between ICD and amiodarone groups. Of the primary prevention trials, AMIOVIRT, MADIT II, DEFINITE, and SCD-HeFT found no evidence of impaired QoL in patients with an ICD. Evidence for an association between ICD shocks and QoL was mixed and seemed to depend on the interval between shocks and QoL assessment. There was no evidence of impaired QoL in patients with an ICD. However, ICD patients must be educated of all possible risks and benefits, including transitory declines in QoL after ICD shocks.

Implantable cardioverter defibrillator in non-ischemic cardiomyopathy: a meta-analysis of randomized controlled trials.

Sudden cardiac death (SCD) is a significant cause of mortality in patients with non-ischemic cardiomyopathy (NICM). Implantable cardioverter defibrillators (ICDs) are currently indicated for the primary prevention of SCD in these patients. Conflicting results from published randomized controlled trials (RCTs) have recently questioned the protective role of ICD in NICM patients to perform an updated meta-analysis of the effect of ICDs on outcomes of NICM patients. We performed a search of PubMed, EMBASE, and Cochrane databases for RCTs comparing ICD to medical therapy in patients with NICM. Outcomes were all-cause mortality, SCD, and cardiac mortality. Mantel-Haenszel (MH) risk ratios (RR) were calculated using random-effects meta-analysis for the outcomes mentioned. Heterogeneity was assessed using I2 statistics and Q-statistic. A total of five RCTs met the inclusion criteria, with a total of 1,503 patients in the ICD group and 1,364 patients in the medical therapy. Compared to medical therapy, ICD use resulted in a 24% relative risk reduction (RRR) of all-cause mortality (RR 0.76, 95% CI 0.64-0.91, P=0.002), and 60% RRR of SCD (RR 0.40, 95% CI 0.18-0.90, P=0.03), but was not associated with a statistically significant benefit in the prevention of cardiac mortality (RR 0.75, 95% CI 0.39-1.44, P=0.39). Limiting the analysis to patients who received an ICD only without cardiac resynchronization therapy (CRT) pacemakers (4 trials, 1,825 patients) showed similar all-cause mortality results with 24% RRR in ICD group (RR 0.76, 95% CI 0.61-0.94, P=0.01). ICD therapy reduces all-cause mortality and SCD in patients with NICM.

Role of implantable cardioverter defibrillator in non-ischemic cardiomyopathy: a systematic review and meta-analysis of prospective randomized clinical trials.

A mortality benefit in patients with implantable cardioverter defibrillator (ICD) in ischemic cardiomyopathy is well established. However, the benefit of ICD implantation in non-ischemic cardiomyopathy (NICM) on total mortality remains uncertain. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) evaluating the role of primary prevention ICD in NICM patients. We performed a systematic review on PubMed, The Cochrane Library, EMBASE, EBSCO, Web of Science, and CINAHL databases from the inception through February 2017 to identify RCT evaluating the role of ICD in NICM patients. Mantel-Haenszel risk ratio (RR) fixed effects model was used to summarize data across treatment arms. If heterogeneity (I 2) ≥25, random effects model was used instead. We analyzed a total of 2573 patients from five RCTs comparing ICD with medical therapy in patients with NICM. The mean follow up for the trials was 48±22months. There was a significant reduction in (a) all-cause mortality (RR 0.84, 95% CI 0.71-0.99, p=0.03) and (b) sudden cardiac death (RR 0.47, 95% CI 0.30-0.73, p<0.001) in ICD group versus medical therapy. Our analysis demonstrates that the use of ICD for primary prevention is associated with a reduction in all-cause mortality and SCD in patients with NICM.

Antibacterial Envelope Is Associated WithLow Infection Rates After Implantable Cardioverter-Defibrillator andCardiac Resynchronization Therapy Device Replacement: Results of the Citadel and Centurion Studies.

This study sought to determine whether the nonabsorbable TYRX Antibacterial Envelope (TYRX) reduces major cardiovascular implantable electronic device (CIED) infections 12 months after implant. TYRX is a monofilament polypropylene mesh impregnated with minocycline and rifampin specifically designed to hold a CIED in place and elute antimicrobials over time. There are limited data on its ability to reduce CIED infections. We prospectively enrolled patients who underwent generator replacement with an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy device (CRT), treated with TYRX. The primary endpoints were major CIED infection and CIED mechanical complications. Given the differences in infection rates among ICD and CRT patients, 3 different control populations were used: a published benchmark rate for ICD patients, and both site-matched and comorbidity-matched controls groups for CRT patients. Overall, a major CIED infection occurred in 5 of 1,129 patients treated with TYRX (0.4%; 95% confidence interval: 0.0% to 0.9%), significantly lower than the 12-month benchmark rate of 2.2% (p= 0.0023). Among the TYRX-treated CRT cohort, the major CIED infection rate was 0.7% compared with an infection rate of 1.0% and 1.3% (p=0.38 and p = 0.02) in site-matched and comorbidity-matched control groups, respectively. Among the ICD group, the 12-month infection rate was 0.2% compared with the published benchmark of 2.2% (p= 0.0052). The most common CIED mechanical complication in study patients was pocket hematoma, which occurred in 18 of the 1,129 patients (1.6%;95% confidence interval: 0.8 to 2.5), which is comparable with a published rate of 1.6%. Use of TYRX was associated with a lower major CIED infection rate. (TYRX™ Envelope for PreventionofInfection Following Replacement With a CRT or ICD; [Centurion]; NCT01043861/NCT01043705).

Right ventricular apical versus non-apical implantable cardioverter defibrillator lead: A systematic review and meta-analysis

IntroductionWe aimed to study the effect of right ventricular implantable cardioverter defibrillator (ICD) lead positioning on clinical outcomes in patients undergoing ICD placement. MethodsA systematic literature search was performed using PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials to identify clinical trials comparing outcomes in patients with ICD leads in apical and non-apical positions. The primary outcome of our study was death at 1-year follow-up. Secondary outcomes studied were “death at 3years”, “total number of shocks”, “appropriate shocks”, “inappropriate shocks” and “cut-to-suture time”. ResultsWe analyzed a total of 3731 patients (2852 in apical and 879 in non-apical ICD groups) enrolled in 4 clinical trials. No significant difference was observed between the apical and non-apical ICD groups in all-cause mortality at 1year (OR 0.88; 95% CI 0.51–1.49, p=0.63; I2=5.32%). Similarly, no differences were seen between the two groups in death at 3years (OR=0.76; 95% CI 0.56–1.04, p=0.08; I2=0%), total number of shocks (OR 0.99; 95% CI 0.81–1.22, p=0.95; I2=0%), appropriate shocks (OR 1.00; 95% CI 0.79–1.27, p=0.99; I2=0%), inappropriate shocks (OR 0.98; 95% CI 0.70–1.37, p=0.91; I2=0%) and cut-to-suture time (Standard mean difference=−0.03; 95% CI −0.20 to 0.14, p=0.73; I2=0%). No publication bias was seen. ConclusionNon-apical RV ICD lead implantation is non-inferior to traditional RV apical position with no significant differences in mortality, total number of shocks, appropriate shocks, inappropriate shocks and procedural time.

Association of Implantable Cardioverter Defibrillators With Survival in Patients With and Without Improved Ejection Fraction

Improvement in left ventricular ejection fraction (EF) to >35% occurs in many patients with reduced EF at baseline. To our knowledge, whether implantable cardioverter defibrillator (ICD) therapy improves survival for these patients is unknown. To examine the efficacy of ICD therapy in reducing risk of all-cause mortality and sudden cardiac death among patients with an EF ≤35% at baseline, with or without an improvement in EF to >35% during follow-up. This retrospective analysis examined data collected in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), which randomly assigned 2521 patients to placebo, amiodarone, or ICD between 1997 and 2001. A subset of 1902 participants (75.4%) of the SCD-HeFT had a repeated assessment of EF a mean (SD) of 13.5 (6) months after randomization. We stratified these patients by EF ≤35% and >35% based on the first repeated EF measurement after randomization and compared all-cause mortality in 649 patients randomized to placebo vs 624 patients randomized to ICD. Follow-up started with the repeated EF assessment. Analysis was performed between January 2016 and July 2016. Implantable cardioverter-defibrillator therapy. All-cause mortality and sudden cardiac death. Of the included 1273 patients, the mean (SD) age was 59 (12) years, and 977 (76.7%) were male and 1009 (79.3%) were white. Repeated EF was >35% in 186 participants (29.8%) randomized to ICD and 185 participants (28.5%) randomized to placebo. During a median follow-up of 30 months, the all-cause mortality rate was lower in the ICD vs placebo group, both in patients whose EF remained ≤35% (7.7 vs 10.7 per 100 person-year follow-up) and in those whose EF improved to >35% (2.6 vs 4.5 per 100 person-year follow-up). Compared with placebo, the adjusted hazard ratio for the effect of ICD on mortality was 0.64 (95% CI, 0.48-0.85) in patients with a repeated EF of ≤35% and 0.62 (95% CI, 0.29-1.30) in those with a repeated EF >35%. There was no interaction between treatment assignment and repeated EF for predicting mortality. Among participants in the SCD-HeFT who had a repeated EF assessment during the course of follow-up, those who had an improvement in EF to >35% accrued a similar relative reduction in mortality with ICD therapy as those whose EF remained ≤35%. Prospective randomized clinical trials are needed to test ICD efficacy in patients with an EF >35%. clinicaltrials.gov Identifier: NCT01114269.

Implantable Cardioverter-defibrillator for Primary Prevention of Sudden Cardiac Death in Non-ischemic Cardiomyopathy

The insertion of implantable cardioverter-defibrillators (ICD) in patients with non-ischemic cardiomyopathy (NICM) has been recommended by recent guidelines. However, current evidence shows limited benefits to inserting ICDs in patients with NICM. Recently, the defibrillator implantation in patients with non-ischemic systolic heart failure (DANISH) trial, a large randomized trial of more than 1,100 patients with NICM, was conducted to compare the primary prevention of all-cause mortality between optimal medical therapy, cardiac resynchronization therapy, and ICD implantation. The DANISH trial revealed no differences in all-cause mortality between the groups after 5 years. However, in patients younger than 68 years of age, the rate of death from any cause was significantly lower in the ICD group compared to the control group. In addition, the rate of sudden cardiac death was lower in the ICD group compared to the control group in patients under 68 years. The results of DANISH will likely change guidelines about the insertion of ICD in patients with NICM, and encourage the use of ICD in patients with NICM. Keywords: Implantable cardioverter-defibrillator; Non-ischemic cardiomyopathy; Sudden cardiac death; Primary prevention 중심 단어: ì‚½ìž í˜• ì œì„¸ë™ê¸°; 비허혈성 심근병증; 심장돌연사; ì¼ì°¨ì  예방

Presence of Implantable Cardioverter-Defibrillators and Wait-List Mortality of Patients Supported with Left Ventricular Assist Devices as Bridge to Heart Transplantation

BackgroundThe role of implantable cardioverter defibrillator (ICD) in reducing mortality in patients with left ventricular assisted devices (LVADs) listed for heart transplant remains unclear. We therefore, sought to interrogate whether ICDs are associated with reduced mortality in patients with LVADs listed for heart transplantation. MethodsWe searched the United Network for Organ Sharing (UNOS) Registry for LVAD patients (age≥18years) with dilated cardiomyopathies listed for heart transplantation (2008-2015). The group was matched by propensity scores with respect to presence of ICD at listing. The primary end-point was waitlist mortality, while secondary endpoints were waitlist mortality, delisting, or cardiovascular cause-specific mortality in patients with and without ICD. ResultsA total of 1444 LVAD patients were included in this analysis (722 with ICD, 722 without ICD). No statistically-significant differences were present between the two groups in demographics, device type, listing status, or hemodynamics. The presence of an ICD was not associated with decreased wait-list mortality (Hazard Ratio 1.19 [0.75-1.88], p=0.46), waitlist mortality/delisting (Hazard Ratio 1.20 [0.86-1.67], p=0.28), or cardiovascular wait-list mortality (HR 1.24 [0.45-3.43], p=0.67) over a median of 5.6months. Only 7 deaths occurred due to arrhythmia/cardiac arrest (2 in the ICD group and 5 in the non-ICD group). ConclusionPresence of ICDs at listing in heart failure patients bridged to transplantation with durable LVADs is not associated with lower waitlist mortality, cardiovascular wait-list mortality or wait-list mortality or delisting; however, there were numerically fewer arrhythmic deaths in the ICD group. Additional prospective studies should be undertaken to confirm these findings.

Abstract 13142: Implantable Cardioverter Defibrillators Continue to Offer Mortality Benefit After Improvement in Ejection Fraction to Above 35%: Results From the Sudden Cardiac Death in Heart Failure Trial

Introduction: Patients (pts) discovered to have low ejection fraction (EF ≤ 35%) frequently show increase in EF to &gt; 35% over time. The efficacy of implantable cardioverter defibrillators (ICD) to improve survival is unknown in these pts. Hypothesis: Mortality benefit with ICD therapy is less in pts whose EF improves to &gt; 35% than those whose EF remains ≤ 35%. Methods: A total of 1875 (74%) participants of the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) had a repeat assessment of EF 13.5 ± 6 months after randomization. We stratified them by EF ≤ 35% and &gt; 35% based on the 1 st repeat EF after randomization and compared all-cause mortality of 649 pts randomized to placebo vs. 624 pts randomized to ICD (602 pts randomized to amiodarone were not analyzed). Follow-up started at the time of 1 st repeat EF assessment. Results: Repeat EF was &gt; 35% in 186 (30%) pts in the ICD group and 185 (29%) pts in the placebo group (mean EF increased from 26±7% to 46±8%). The all-cause mortality rate was lower in the ICD group vs. placebo group, both in pts whose EF remained ≤ 35% and in those whose EF improved to &gt; 35% (Table). Compared to placebo, the unadjusted hazard ratio for ICD effect on mortality was 0.72 (95% CI 0.55-0.95) in pts with repeat EF ≤ 35% and 0.58 (95% CI 0.29-1.17) in those with repeat EF &gt; 35%. After adjustment for potential confounders, the estimated effect of ICD was 0.64 (95% CI 0.48-0.85) and 0.62 (95% CI 0.29-1.30) in patients with repeat EF ≤ 35% or &gt; 35%, respectively (Table). We found no evidence of an interaction between treatment assignment and repeat EF for prediction of mortality (p=0.93), suggesting that the ICD effect was similar in patients with EF ≤ 35% or &gt; 35%. Conclusions: Pts with an improvement in EF to &gt; 35% accrued a similar relative reduction in mortality with ICD therapy as those whose EF remained ≤ 35%. However, the absolute benefit of ICD therapy was less in pts with repeat EF &gt; 35% due to the lower mortality risk in this group.

Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure

BackgroundThe benefit of an implantable cardioverter–defibrillator (ICD) in patients with symptomatic systolic heart failure caused by coronary artery disease has been well documented. However, the evidence for a benefit of prophylactic ICDs in patients with systolic heart failure that is not due to coronary artery disease has been based primarily on subgroup analyses. The management of heart failure has improved since the landmark ICD trials, and many patients now receive cardiac resynchronization therapy (CRT).MethodsIn a randomized, controlled trial, 556 patients with symptomatic systolic heart failure (left ventricular ejection fraction, ≤35%) not caused by coronary artery disease were assigned to receive an ICD, and 560 patients were assigned to receive usual clinical care (control group). In both groups, 58% of the patients received CRT. The primary outcome of the trial was death from any cause. The secondary outcomes were sudden cardiac death and cardiovascular death.ResultsAfter a median follow-up period of 67.6 months, the primary outcome had occurred in 120 patients (21.6%) in the ICD group and in 131 patients (23.4%) in the control group (hazard ratio, 0.87; 95% confidence interval [CI], 0.68 to 1.12; P=0.28). Sudden cardiac death occurred in 24 patients (4.3%) in the ICD group and in 46 patients (8.2%) in the control group (hazard ratio, 0.50; 95% CI, 0.31 to 0.82; P=0.005). Device infection occurred in 27 patients (4.9%) in the ICD group and in 20 patients (3.6%) in the control group (P=0.29).ConclusionsIn this trial, prophylactic ICD implantation in patients with symptomatic systolic heart failure not caused by coronary artery disease was not associated with a significantly lower long-term rate of death from any cause than was usual clinical care. (Funded by Medtronic and others; DANISH ClinicalTrials.gov number, NCT00542945.)