A Longitudinal Study of Mitral Regurgitation Detected after Acute Myocardial Infarction.
Sharma H., Yuan M., Shakeel I., Hodson J., Radhakrishnan A., Brown S., May J., O'Connor K., Zia N., Doshi SN., Hothi SS., Townend JN., Myerson SG., Ludman PF., Steeds RP., Nadir MA.
BACKGROUND: Mitral regurgitation (MR) is common following myocardial infarction (MI). However, the subsequent trajectory of MR, and its impact on long-term outcomes are not well understood. This study aimed to examine the change in MR severity and associated clinical outcomes following MI. METHODS: Records of patients admitted to a single centre between 2016 and 2017 with acute MI treated by percutaneous coronary intervention (PCI) were retrospectively examined. RESULTS: 294/1000 consecutive patients had MR on baseline (pre-discharge) transthoracic echocardiography (TTE), of whom 126 (mean age: 70.9 ± 11.4 years) had at least one follow-up TTE. At baseline, most patients had mild MR (n = 94; 75%), with n = 30 (24%) moderate and n = 2 (2%) severe MR. Significant improvement in MR was observed at the first follow-up TTE (median 9 months from baseline; interquartile range: 3-23), with 36% having reduced severity, compared to 10% having increased MR severity (p < 0.001). Predictors of worsening MR included older age (mean: 75.2 vs. 66.7 years; p = 0.003) and lower creatinine clearance (mean: 60 vs. 81 mL/min, p = 0.015). Change in MR severity was significantly associated with prognosis: 16% with improving MR reached the composite endpoint of death or heart failure hospitalisation at 5 years, versus 44% (p = 0.004) with no change, and 59% (p < 0.001) with worsening MR. CONCLUSIONS: Of patients with follow-up TTE after MI, MR severity improved from baseline in approximately one-third, was stable in around half, with the remainder having worsening MR. Patients with persistent or worsening MR had worse clinical outcomes than those with improving MR.