Mortality, sudden death and indication for cardioverter defibrillator implantation in a dialysis population

Effect of Implanted Defibrillator on Mortality in Patients With Chronic Kidney Disease

The beneficial role of implantable cardioverter defibrillators (ICDs) in patients with chronic kidney disease (CKD) is controversial. This meta-analysis aimed to evaluate the effect of ICD on mortality in patients with CKD. A literature search was conducted for studies reporting the effect of ICD on all-cause mortality in patients with CKD (estimated glomerular filtration rate <60 ml/min/1.73 m²). The search was not restricted to time or publication status. The search included the following databases: Ovid MEDLINE, EMBASE, Scopus, Web of Science, Google Scholar, and EBSCO CINAHL. The primary end point was all-cause mortality. The minimum duration of follow-up required for inclusion was 1 year. The literature search identified 834 studies, of which 14 studies with 70,661 patients were included. Mean follow-up was 39 months (12 to 81 months). For all patients with CKD, ICD was associated with lower all-cause mortality (log hazard ratio [HR] -0.247, standard error [SE] 0.101, p = 0.015). Heterogeneity: degree of freedom = 13 (p <0.01), I² = 97.057; test for overall effect: Z = -2.431 (p = 0.015). When further stratified based on dialysis, patients with CKD without the need for dialysis had significantly lower mortality (log HR -0.211, SE 0.095, p = 0.026), with a similar trend in patients who underwent dialysis (log HR -0.262, SE 0.134, p = 0.051). ICD implantation is associated with a significant mortality benefit in patients with CKD.

Sudden cardiac death in dialysis patients: different causes and management strategies

Sudden cardiac death (SCD) represents a major cause of death in end-stage kidney disease (ESKD). The precise estimate of its incidence is difficult to establish because studies on the incidence of SCD in ESKD are often combined with those related to sudden cardiac arrest (SCA) occurring during a haemodialysis (HD) session. The aim of the European Dialysis Working Group of ERA-EDTA was to critically review the current literature examining the causes of extradialysis SCD and intradialysis SCA in ESKD patients and potential management strategies to reduce the incidence of such events. Extradialysis SCD and intradialysis SCA represent different clinical situations and should be kept distinct. Regarding the problem, numerically less relevant, of patients affected by intradialysis SCA, some modifiable risk factors have been identified, such as a low concentration of potassium and calcium in the dialysate, and some advantages linked to the presence of automated external defibrillators in dialysis units have been documented. The problem of extra-dialysis SCD is more complex. A reduced left ventricular ejection fraction associated with SCD is present only in a minority of cases occurring in HD patients. This is the proof that SCD occurring in ESKD has different characteristics compared with SCD occurring in patients with ischaemic heart disease and/or heart failure and not affected by ESKD. Recent evidence suggests that the fatal arrhythmia in this population may be due more frequently to bradyarrhythmias than to tachyarrhythmias. This fact may partly explain why several studies could not demonstrate an advantage of implantable cardioverter defibrillators in preventing SCD in ESKD patients. Electrolyte imbalances, frequently present in HD patients, could explain part of the arrhythmic phenomena, as suggested by the relationship between SCD and timing of the HD session. However, the high incidence of SCD in patients on peritoneal dialysis suggests that other risk factors due to cardiac comorbidities and uraemia per se may contribute to sudden mortality in ESKD patients.

Association between CRT(D)/ICD and renal insufficiency: A systematic review and meta-analysis

Cardiac resynchronization therapy with or without a defibrillator (CRT(D)) and implantable cardioverter defibrillator (ICD) may reduce the risk of arrhythmia or heart failure-specific mortality and improves the prognosis of patients with chronic kidney disease (CKD) or dialysis. The aim of this study was to perform a meta-analysis investigating the relationship between CRT(D)/ICD and renal insufficiency. Cochrane Library, Web of Science, Embase, and Pubmed were systematically searched from inception to 29 October 2019. We included studies that report all-cause mortality of patients with renal insufficiency who received CRT(D)/ICD therapy. Twenty-six studies (n = 119,263) were included, exploring the relationship between CRT(D)/ICD and renal insufficiency from two aspects: (1) Compared with ICD-only, CRT(D) was associated with lower risk of all-cause mortality in CKD patients (odds ratios (OR) = 0.67; 95% confidence interval (CI), 0.60 to 0.75). For non-primary prevention (secondary prevention or both), the analysis revealed a lower risk of all-cause mortality in the ICD group than in the no-ICD group (OR = 0.47; 95% CI, 0.40 to 0.55). (2) CKD increased all-cause mortality in comparison with control group (OR = 2.12; 95% CI, 1.85 to 2.44), and so did dialysis (OR = 2.53; 95% CI, 2.34 to 2.73). Furthermore, compared with CKD3 (eGFR: 30-59 ml/min/1.73 m² ), CKD4/5 (eGFR <30 ml/min/1.73 m² ) was observed to have a significantly higher risk of all-cause mortality (OR = 2.70; 95% CI, 1.93 to 3.80). This review shows a clear association between CRT(D)/ICD and renal insufficiency in the aspect of all-cause mortality, and may provide a reference for the clinical application of CRT(D)/ICD.

Efficacy of Implantable Cardioverter-defibrillators for Secondary Prevention of Sudden Cardiac Death in Patients with End-stage Renal Disease

End-stage renal disease (ESRD) constitutes a major burden on the health-care system in the United States, with more than 300,000 patients nationwide being treated with renal replacement therapy. Very few studies to date have evaluated the benefit of implantable cardioverter-defibrillator (ICD) implantation for secondary prevention in patients with ESRD. In this study, we evaluated the efficacy of secondary-prevention ICDs in reducing all-cause mortality in patients on dialysis using the United States Renal Data System (USRDS) database. We queried the USRDS for relevant data between 2004 and 2010. Patients with diagnoses of ventricular fibrillation (VF), ventricular tachycardia (VT), or sudden cardiac arrest (SCA) were included in the study. Patients were excluded from the analysis if they were younger than 18 years; had missing age, sex, or race/ethnicity information; had experienced myocardial infarction; or had an ICD in situ at the time of VF, VT, or SCA diagnosis. The primary endpoint of this study was to determine the efficacy of secondary-prevention ICDs in reducing all-cause mortality in patients on dialysis. A total of 1,442 patients (3.4%) with ESRD had ICD insertion. Patients who received an ICD were predominantly younger, white males with lower Charlson Comorbidity Index and with fewer cardiovascular events. Survival at two years was 53% among those with an ICD relative to 27% among those without an ICD. In this study, we observed a substantial decrease in mortality in patients receiving an ICD for secondary prevention when compared with a cohort of similar patients with a history of VF, VT, or SCA.

Implantable Cardioverter Defibrillators and Chronic Kidney Disease

Use of implantable cardioverter defibrillators (ICDs) is the treatment of choice for heart failure patients with ejection fraction <35% to prevent sudden cardiac death. Whether this benefit remains among patients with chronic kidney disease (CKD) or end stage renal disease (ESRD) is yet to be elucidated. We conducted a systematic review of studies in PubMed that have investigated the use of ICDs among patients with CKD or ESRD. From the 470 studies identified, we selected 42 for the current review. Patients with CKD/ESRD were more likely to get antitachycardia pacing or shocks and had higher cardiac and/or all-cause mortality compared to patients without CKD/ESRD. These associations had an inverse dose-response effect with worse outcomes with decreasing kidney function. In conclusion, use of ICDs in CKD/ESRD is associated with increased antitachycardia pacing/shocks and mortality suggesting that their routine use in this patient population may be associated with more adverse outcomes than benefits.

Do Implantable Cardioverter Defibrillators Reduce Mortality in Patients With Chronic Kidney Disease at All Stages?

The benefits of implantable cardioverter defibrillator (ICD) implantation in chronic kidney disease (CKD) patients with high sudden cardiac death (SCD) risk are uncertain. To clarify the effects of receiving an ICD in CKD patients, we conducted this meta-analysis to identify the effects of ICDs on patients with CKD, including those on dialysis. We searched the Cochrane library, EMBASE, PubMed, and clinical trials for studies published before July 2016. Eleven studies including 20,196 CKD patients were considered for inclusion. The pooled analysis suggested that patients with an estimated glomerular filtration rate (eGFR) < 60 mL/minute/1.73 m2 would benefit from receiving treatments with ICDs compared with patients without an ICD device (aHR = 0.74; 95% confidence interval [CI], 0.63 to 0.86). [corrected]. This is the first report of a subgroup analysis on the survival rate of ICD implantation in CKD patients according to an eGFR group. The subgroup analysis indicated a similar protective association of ICDs in stage 3 (aHR = 0.71; 95% CI, 0.61 to 0.82) and 5 (aHR = 0.71; 95% CI, 0.54 to 0.92) CKD patients [corrected] compared with the control group. However, there was no significant improvement in all-cause mortality in stage 4 CKD patients (aHR = 1.02; 95%CI, 0.75 to 1.37) [corrected]. This is the first meta-analysis reporting that ICD implantation reduces all-cause mortality in stage 3 and 5 [corrected] CKD patients. However, the data do not indicate there is any benefit to ICD implantation in stage 4 [corrected] CKD patients.