Abstract 16054: Cardiac Resynchronization Therapy is an Effective Therapy for Patients With Impaired Renal Function
Introduction: Cardiac Resynchronization Therapy (CRT) has been demonstrated to reduce mortality and hospitalization for heart failure (HF) in HF patients with left ventricular systolic dysfunction and wide QRS duration. We wished to determine if patients with impaired renal function also benefit from CRT.
Methods: In the RAFT Study, 1798 patients with LVEF ≤ 30 percent, QRS ≥ 120 msec (≥ 200 msec paced) and NYHA II or III HF were randomized to receive an ICD or ICD-CRT. The primary and secondary outcomes were a composite of death or HF hospitalization, death, HF hospitalization. Renal function - serum creatinine, serum urea and estimated glomerular filtration rater (eGFR) were determined at baseline. Survival-analysis techniques were used to compare ICD with ICD-CRT groups with respect to outcomes in patients with preserved renal function (eGFR ≥ 60) and patients with impaired renal function (eGFR < 60). Patients with impaired renal function were further divided into pre-renal impairment (creatinine/urea ratio < 13.1) or intra-renal impairment (creatinine/urea ratio ≥ 13.1).
Results: In patients with impaired renal function (eGFR < 60, n=901) CRT reduced all cause mortality or HF hospitalization [HR 0.71 (95% CI 0.58, 0.86)]; all cause mortality [HR 0.59 (95% CI 0.35, 0.98)]; and HF hospitalization [HR 0.61 (95% CI 0.47, 0.78)] to a similar degree as those with preserved renal function (eGFR ≥ 60, n=881). In patients with pre-renal impairment (eGFR < 60 and creatinine/urea ratio < 13.1, n=444), CRT reduced mortality or HF hospitalization [HR 0.70 (95% CI 0.54, 0.92)]; a trend to reduce mortality [HR 0.74 (95% CI 0.54,1.02)]; and reduced hospitalization for HF [HR 0.58 (95% CI 0.41, 0.82)]. Similarly, in patients with intra-renal impairment (eGFR < 60 creatinine/urea ratio ≥ 13.1, n=415), CRT reduced mortality or HF hospitalization [HR 0.72 (95% CI 0.53, 0.98)]; a trend to reduce mortality [HR 0.76 (95% CI 0.52, 1.10)]; and reduced HF hospitalization [HR 0.63 (95% CI 0.42, 0.96)].
Conclusions: CRT, in addition to ICD and medical therapy, reduces clinical outcomes in HF patients with preserved renal function and in patients with impaired renal function. In the setting of impaired renal function, HF patients with pre-renal or intra-renal impairment benefited from CRT.
- © 2011 by American Heart Association, Inc.