Implantable cardioverter-defibrillators in patients with CKD: a propensity-matched mortality analysis.

BACKGROUND AND OBJECTIVES: Benefits of transvenous implantable cardioverter-defibrillators (ICDs) in prevention of sudden cardiac death among the general population are proven. However, the benefit of ICDs remains unclear in CKD. A propensity-matched analysis was conducted to examine the survival benefits of ICDs placed for primary prevention in those with CKD not on dialysis (eGFR<60 ml/min per 1.73 m(2)).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The Cleveland Clinic CKD registry was utilized to identify individuals who had an echocardiogram at the institution (between 2001 and October 2011). A propensity score of the likelihood of receiving an ICD was developed with the following variables: demographics, comorbid conditions, use of cardioprotective medications, eGFR, left ventricular ejection fraction, and ventricular arrhythmia. One-to-one greedy matching was used with 0.1 caliper width to match patients with and without an ICD. A Cox proportional hazards model was used to examine survival of matched patients with and without an ICD.

RESULTS: This study included 1053 ICD patients and 9435 potential controls. Of 1053 ICD patients (60%), 631 were matched to the control group. During a median follow-up of 2.9 years (25th and 75th percentiles, 1.5, 4.7), 578 patients died. After adjusting for covariates, the hazard of mortality among propensity-matched patients was 0.69 (95% confidence interval [95% CI], 0.59 to 0.82) for the ICD group compared with the non-ICD group. A significant interaction was found between ICDs and eGFR (P=0.04). Presence of an ICD was associated with a lower risk of death among those with eGFRs of 45-59 ml/min per 1.73 m(2) (hazard ratio [HR], 0.58; 95% CI, 0.44 to 0.77) and 30-44 ml/min per 1.73 m(2) (HR, 0.65; 95% CI, 0.50 to 0.85), but not among those with eGFRs<30 ml/min per 1.73 m(2) (HR, 0.98; 95% CI, 0.71 to 1.35).

CONCLUSIONS: Transvenous ICDs placed for primary prevention are associated with a survival benefit in those with stage 3 CKD, but not in those with stage 4 CKD.