AIMS
To evaluate the prognostic role of echocardiographic parameters assessing secondary mitral regurgitation (SMR) severity and left ventricular dimension, including proportionate versus disproportionate SMR, in Mitraclip recipients.
METHODS AND RESULTS
We analysed 137 patients undergoing Mitraclip for SMR at 3 centres. SMR was classified as proportionate or disproportionate based on the median value of the ratio between effective regurgitant orifice area (EROA) and left ventricular end-diastolic volume (LVEDV). The primary end-point was a composite of cardiovascular mortality and heart failure hospitalization at 2-year follow-up. Mean age was 70±10 years, 80% were males, and median EuroSCORE II was 5.7%. No differences were observed in disproportionate compared to proportionate group except for a more severe NYHA class and their expected higher EROA and lower LVEDV. Number of clips deployed, device success and procedural success were similar between the two groups. Residual mitral regurgitation (MR)>1+ at 30-day was more common among patients with EROA>0.42 cm2 compared to those with EROA≤0.42 cm2 (81.3% vs. 58%; p=0.004). Cumulative incidence and relative risk of primary end-point was independent from any echocardiographic parameter, including the presence of disproportionate SMR. The only independent predictors of clinical events were EuroSCORE II>8%, NYHA class and residual MR>1+ at 30-day.
CONCLUSIONS
Echocardiographic parameters, including the EROA/LVEDV ratio, have not independent prognostic value in patients undergoing MitraClip. High surgical risk, advanced symptoms and non-optimal MR reduction increase the relative risk of 2-year clinical events.