Predictors of mortality in patients with chronic kidney disease and an implantable defibrillator: an EPGEN substudy

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.

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.

Does the Implantable Cardioverter-Defibrillator Benefit Vary With the Estimated Proportional Risk of Sudden Death in Heart Failure Patients?

BACKGROUND

Prediction of which heart failure patients are most likely to die of sudden death vs. non-sudden death is an important factor in determining who will benefit the most from an ICD.

OBJECTIVE

We developed the Seattle Proportional Risk Model (SPRM) to estimate the proportion of total mortality due to sudden death. We prospectively validated the model in HF-ACTION and tested whether the ICD benefit varied with the SPRM.

METHODS

Among 2331 patients enrolled, 1947 patients were retained for analysis over a median follow-up of 2.5 years. The SPRM was calculated using age, gender, diabetes, BMI, SBP, EF, NYHA, sodium, creatinine, and digoxin use.

RESULTS

ICD use (ICD or CRT-D) was present prior to death in 1204 patients (62%). SPRM was predictive of sudden death vs. non-sudden death in those without an ICD (P=0.002). The hazard ratio representing ICD versus no ICD was 0.63 for all-cause mortality (P=0.0002). The ICD benefit varied with the SPRM for all-cause mortality (P=0.001), with a greater benefit in those with a higher conditional probability of sudden death.

CONCLUSIONS

In an ambulatory NYHA II-IV HF population and EF ≤35%, the SPRM was predictive of the proportional risk of sudden vs. non-sudden death. ICDs were associated with a decreased risk of all-cause mortality by 37% and the ICD benefit varied with the SPRM. The SPRM may have utility in risk stratifying patients for a primary prevention ICD.

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

IMPORTANCE

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.

OBJECTIVE

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.

DESIGN, SETTINGS, AND PARTICIPANTS

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.

EXPOSURES

Placement of an ICD.

MAIN OUTCOMES AND MEASURES

All-cause death, hospitalizations due to heart failure, and any-cause hospitalizations.

RESULTS

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.

CONCLUSIONS AND RELEVANCE

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.

Denervated Myocardium Is Preferentially Associated With Sudden Cardiac Arrest in Ischemic Cardiomyopathy: A Pilot Competing Risks Analysis of Cause-Specific Mortality

BACKGROUND

Previous studies have identified multiple risk factors that are associated with total cardiac mortality. Nevertheless, identifying specific factors that distinguish patients at risk of arrhythmic death versus heart failure could better target patients likely to benefit from implantable cardiac defibrillators, which have no impact on nonsudden cardiac death.

METHODS AND RESULTS

We performed a pilot competing risks analysis of the National Institutes of Health-sponsored PAREPET trial (Prediction of Arrhythmic Events with Positron Emission Tomography). Death from cardiac causes was ascertained in subjects with ischemic cardiomyopathy (n=204) eligible for an implantable cardiac defibrillator for the primary prevention of sudden cardiac arrest after baseline clinical evaluation and imaging at enrollment (positron emission tomography and 2-dimensional echo). Mean age was 67±11 years with an ejection fraction of 27±9%, and 90% were men. During 4.1 years of follow-up, there were 33 sudden cardiac arrests (arrhythmic death or implantable cardiac defibrillator discharge for ventricular fibrillation or ventricular tachycardia >240 bpm) and 36 nonsudden cardiac deaths. Sudden cardiac arrest was correlated with a greater volume of denervated myocardium (defect of the positron emission tomography norepinephrine analog ¹¹C-hydroxyephedrine), lack of angiotensin inhibition therapy, elevated B-type natriuretic peptide, and larger left ventricular end-diastolic volume index. In contrast, nonsudden cardiac death was associated with a higher resting heart rate, older age, elevated creatinine, larger left atrial volume index, and larger left ventricular end-diastolic volume index.

CONCLUSIONS

Distinct clinical, laboratory, and imaging variables are associated with cause-specific cardiac mortality in primary-prevention candidates with ischemic cardiomyopathy. If prospectively validated, these multivariable associations may help target specific therapies to those at the greatest risk of sudden and nonsudden cardiac death.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov. Unique identifier: NCT01400334.

Influence of renal function on mortality and ventricular arrhythmias in patients undergoing first implantable cardioverter-defibrillator generator replacement

BACKGROUND

Impaired renal function is associated with increased mortality among patients with implantable cardioverter-defibrillators (ICDs). The relationship between renal function at time of ICD generator replacement and subsequent appropriate ICD therapies is not known.

METHODS AND RESULTS

We identified 441 patients who underwent first ICD generator replacement between 2000 and 2011 and had serum creatinine measured within 30 days of their procedure. Patients were divided into tertiles based on estimated glomerular filtration rate (eGFR). Adjusted Cox proportional hazard and competing risk models were used to assess relationships between eGFR and subsequent mortality and appropriate ICD therapy. Median eGFR was 37.6, 59.3, and 84.8 mL/min/1.73 m(2) for tertiles 1-3, respectively. Five-year Kaplan-Meier survival probability was 34.8%, 61.4%, and 84.5% for tertiles 1-3, respectively (P < 0.001). After multivariable adjustment, compared to tertile 3, worse eGFR tertile was associated with increased mortality (HR 2.84, 95% CI [1.36-5.94] for tertile 2; HR 3.84, 95% CI [1.81-8.12] for tertile 1). At 5 years, 57.0%, 58.1%, and 60.2% of patients remained free of appropriate ICD therapy in tertiles 1-3, respectively (P = 0.82). After adjustment, eGFR tertile was not associated with future appropriate ICD therapy. Results were unchanged in an adjusted competing risk model accounting for death.

CONCLUSIONS

At time of first ICD generator replacement, lower eGFR is associated with higher mortality, but not with appropriate ICD therapies. The poorer survival of ICD patients with reduced eGFR does not appear to be influenced by arrhythmia status, and there is no clear proarrhythmic effect of renal dysfunction, even after accounting for the competing risk of death.

A meta-analysis of mortality in end-stage renal disease patients receiving implantable cardioverter defibrillators (ICDs)

Data on the effectiveness of implantable implantable cardioverter defibrillators (ICDs) with respect to reducing mortality in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD) are lacking. The purpose of this meta-analysis was to compare the mortality of patients with ESRD who have received and not received an ICD. A search was conducted on January 31, 2013 of Medline, Cochrane, EMBASE, and Google Scholar. Studies were selected for inclusion based on the following criteria. 1) Randomized controlled trial. 2) ESRD patients with heart failure. 3) Device therapy (ICD, CRT-defibrillator [CRT-D]) used to treat heart failure. 4) Primary outcome is survival analysis. 5) Retrospective study if survival analysis was performed. The primary outcome was overall survival (OS), and the secondary outcome was 2-year survival. Odds ratios (ORs) with 95% confidence intervals (CI) were calculated, and a χ2-based test of homogeneity was performed. Three studies were included in the analysis. The combined OR for OS was 2.245 (95% CI 1.871 to 2.685, P<0.001), indicating that patients with an ICD had a significantly higher OS than those without an ICD. The combined OR for 2-year survival was 2.312 (95% CI 1.921 to 2.784, P<0.001), indicating that patients with an ICD had a significantly higher 2-year survival rate than those without an ICD. The use of ICD in patients with ESRD is associated with an increase in the OS and the 2-year survival rate.

Mortality in patients on renal replacement therapy and permanent cardiac pacemakers

End stage renal disease is a relatively frequent disease with high mortality due to cardiac causes. Permanent pacemaker (PM) implantation rates are also very common; thus combination of both conditions is not unusual. We hypothesized that patients with chronic kidney disease with a PM would have significantly higher mortality rates compared with end stage renal disease patients without PM. Our objectives were to analyze mortality of patients on renal replacement therapy with PM. 2778 patients were on renal replacement therapy (RRT) and 110 had a PM implanted during the study period. To reduce the confounding effects of covariates, a propensity-matched score was performed. 52 PM patients and 208 non-PM matched patients were compared. 41% of the PM were implanted before entering the RRT program and 59% while on RRT. Mortality was higher in the PM group. Cardiovascular disease and infections were the most frequent causes of death. Propensity analysis showed no differences in long-term mortality between groups. We concluded that in patients on RRT and PM mortality rates are higher. Survival curves did not differ from a RRT propensity-matched group. We concluded that the presence of a PM is not an independent mortality risk factor in RRT patients.

Risk of sudden cardiac death in chronic kidney disease

The review discusses the epidemiology and the possible underlying mechanisms of sudden cardiac death (SCD) in chronic kidney disease (CKD), and highlights the unmet clinical need for noninvasive risk stratification strategies in these patients. Although renal dysfunction shares common risk factors and often coexists with atherosclerotic cardiovascular disease, the presence of renal impairment increases the risk of arrhythmic complications to an extent that cannot be explained by the severity of the atherosclerotic process. Renal impairment is an independent risk factor for SCD from the early stages of CKD; the risk increases as renal function declines and reaches very high levels in patients with end-stage renal disease on dialysis. Autonomic imbalance, uremic cardiomyopathy, and electrolyte disturbances likely play a role in increasing the arrhythmic risk and can be potential targets for treatment. Cardioverter defibrillator treatment could be offered as lifesaving treatment in selected patients, although selection strategies for this treatment mode are presently problematic in dialyzed patients. The review also examines the current experience with risk stratification tools in renal patients and suggests that noninvasive electrophysiological testing during dialysis may be of clinical value as it provides the necessary standardized environment for reproducible measurements for risk stratification purposes.