Survival Implication of Left Ventricular End-Systolic Diameter in Mitral Regurgitation Due to Flail Leaflets

Objectives This study analyzed the association of left ventricular end-systolic diameter (LVESD) with survival after diagnosis in organic mitral regurgitation (MR) due to flail leaflets.Background LVESD is a marker of left ventricular function in patients with organic MR but its association to survival after diagnosis is unknown.Methods The MIDA (Mitral Regurgitation International Database) registry is a multicenter registry of echocardiographically diagnosed organic MR due to flail leaflets. We enrolled 739 patients with MR due to flail leaflets (age 65 +/- 12 years; ejection fraction: 65 +/- 10%) in whom LVESD was measured (36 +/- 7 mm).Results Under conservative management, 10-year survival and survival free of cardiac death were higher with LVESD <40 mm versus >= 40 mm (64 +/- 5% vs. 48 +/- 10%; p < 0.001, and 73 +/- 5% vs. 63 +/- 10%; p = 0.001). LVESD >= 40 mm independently predicted overall mortality (hazard ratio [ HR]: 1.95, 95% confidence interval [ CI]: 1.01 to 3.83) and cardiac mortality (HR: 3.09, 95% CI: 1.35 to 7.09) under conservative management. Mortality risk increased linearly with LVESD >40 mm (HR: 1.15, 95% CI: 1.04 to 1.27 per 1-mm increment). During the entire follow-up (including post-surgical), LVESD >= 40 mm independently predicted overall mortality (HR: 1.86, 95% CI: 1.24 to 2.80) and cardiac mortality (HR: 2.14, 95% CI: 1.29 to 3.56), due to persistence of excess mortality in patients with LVESD >= 40 mm after surgery (HR: 1.86, 95% CI: 1.11 to 3.15 for overall death, and HR: 1.81, 95% CI: 1.05 to 3.54 for cardiac death).Conclusions In MR due to flail leaflets, LVESD >40 mm is independently associated with increased mortality under medical management but also after mitral surgery. These findings support prompt surgical rescue in patients with LVESD >= 40 mm but also suggest that best preservation of survival is achieved in patients operated before LVESD reaches 40 mm.