Treatment strategies for acute coronary syndrome with severe mitral regurgitation and their effects on short- and long-term prognosis

Mitral regurgitation (MR) of even mild severity affects the prognosis of patients with acute coronary syndrome (ACS). The present study retrospectively analyzed 1,142 patients with ACS and MR of varying severity. Of the 95 patients with severe MR, 57 (60%) underwent primary percutaneous coronary intervention only and 38 (40%) underwent coronary artery bypass grafting (CABG) and mitral valve replacement (MVR). The severity of MR was significantly associated with the risk of heart failure but not with in-hospital or long-term mortality. In patients with severe MR, in-hospital mortality was no greater in those treated with CABG and MVR than in those treated with percutaneous coronary intervention alone. However, the incidence of long-term hard events (heart failure and all-cause mortality) was lower in those who had received the combined treatment. Multivariate analysis showed that, compared to percutaneous coronary intervention alone, CABG combined with MVR at the acute phase of ACS resulted in a significantly improved prognosis (odds ratio 0.172, 95% confidence interval 0.046 to 0.649, p = 0.009), even after adjusting for age, left ventricular filling pressure, and ejection fraction. In conclusion, the severity of MR in patients with ACS is associated with long-term heart failure events. Even at the acute phase of ACS, CABG combined with MVR results in an acceptable in-hospital mortality rate. The combined strategy also reduced the long-term hard events.