Response to Cardiac Resynchronization Therapy Across Chronic Kidney Disease Stages

INTRODUCTION: Limited data is available on the effect of severe chronic kidney disease (CKD) on the response to cardiac resynchronization therapy (CRT) as these patients are often excluded from trials. We therefore aimed to assess the effect of CRT on renal function, reverse remodeling and outcome across all stages of CKD in a large patient population of CRT recipients.

METHODS: 798 consecutive heart failure (HF) patients undergoing CRT implantation between October 2008 and September 2016 were retrospectively evaluated. Renal function was available at baseline and 6 months following CRT. Remodeling based on LVESV/LVEF and clinical outcome was assessed using a combined endpoint of all-cause mortality and HF hospitalization.

RESULTS: Median baseline eGFR was 62.8 [43.6-77.8] ml/min/1.73m2. 33.6% of patients were in CKD stage 3, 11.0% in stage 4, and 1.1% in stage 5. LVEF and LVESV improved across all CKD stages, however patients with CKD stage 1-2 exhibited a greater degree of improvement in LVEF (median 15% vs. 10%, P<0.001) and LVESV (median -37.2% vs. -29.9%, P<0.001) compared to patients with CKD stage 3-5. Despite a greater degree of reverse remodeling in CKD stage 1-2, the most accurate cutoff of remodeling predicting good clinical outcome was lower for patients with CKD stage 3-5, respectively 5.5% vs. 9.5% (LVEF), and -6.67% vs. -12.41% (LVESV).

CONCLUSIONS: CRT results in reverse remodeling across all stages of CKD, although to a lesser extent in patients with renal dysfunction (CKD stage 3-5). However, patients with CKD derive benefit on outcome at a lesser degree of remodeling.