Cardiac resynchronization therapy improves renal function in human heart failure with reduced glomerular filtration...

Renal dysfunction is an important independent prognostic factor in heart failure (HF). Cardiac resynchronization therapy (CRT) improves functional status and left ventricular (LV) function in HF patients with ventricular dyssynchrony, but the impact of CRT on renal function is less defined. We hypothesized that CRT would improve glomerular filtration rate as estimated by the abbreviated Modification of Diet in Renal Disease equation (eGFR).

The Multicenter InSync Randomized Clinical Evaluation (MIRACLE) study evaluated CRT in HF patients with NYHA Class III-IV, ejection fraction or=130 ms. Patients were evaluated before and 6 months after randomization to control (n = 225) or CRT (n = 228). Patients were categorized according to their baseline eGFR: >or=90 (category A), 60

CRT increased eGFR and reduced blood urea nitrogen in HF patients with moderately reduced baseline eGFR. By improving cardiac function, CRT can indirectly improve renal function, underscoring the importance of cardiorenal interaction and providing another mechanism for the beneficial effects of CRT.