Prognostic implications of mitral regurgitation in patients after cardiac resynchronization therapy

Aim Mitral regurgitation (MR) is a common finding in patients with heart failure with debatable effects on prognosis. Reduction in MR is one of the mechanisms by which cardiac resynchronization therapy (CRT) exerts its beneficial effects. We investigated the prognostic impact of baseline MR and MR persistence after CRT on outcomes of treated patients. Methods and results We prospectively followed 1122 CRT patients (66.4 ± 10.3 years, 78% male) who were stratified according to baseline MR severity as having MR− (degree 0–1; n = 508, 45%) or MR+ (degrees 2–3–4; n = 614, 55%). In 916 patients (82%) with MR severity data available at 1‐year follow‐up, the annual mortality rate was 3.4 and 6.0 per patient‐year in the MR− and MR+ group, respectively, with a 1‐year incidence rate ratio (IRR) of 1.76 (P