Response to Cardiac Resynchronization Therapy Across Chronic Kidney Disease Stages

Limited data are available concerning the effect of severe chronic kidney disease (CKD) on the response to cardiac resynchronization therapy (CRT) because these patients are commonly excluded from trials. Therefore, we 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 recipients of CRT.

We retrospectively evaluated 798 consecutive patients with heart failure who were undergoing CRT implantation between October 2008 and September 2016. Renal function data were available at baseline and at 6 months following CRT. Remodeling based on left ventricular end diastolic volume/left ventricular ejection fraction (LVESV/LVEF) and clinical outcome was assessed using a combined endpoint of all-cause mortality and hospitalization because of heart failure.

Median baseline estimated glomerular filtration rate was 62.8 (43.6-77.8) mL/min/1.73 m². Of the patients, 33.6% 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 stages 1 and 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 stages 3-5. Despite a greater degree of reverse remodeling in CKD stages 1 and 2, the most accurate cut-off 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).

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.