The Association Between Mitral Regurgitation and Long-Term Outcomes in Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention: A Retrospective Large Sample Cohort Study.

Abstract

Background: The relationship between mitral regurgitation (MR) and long-term outcomes in Chinese patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) remains scarce. This study aimed to elucidate the connection between MR and long-term clinical outcomes following AMI treated with PCI.

Methods: In this retrospective study 6940 patients who were diagnosed with AMI were consecutively enrolled from General Hospital of Ningxia Medical University (2014-2019). The included AMI patients were divided into no MR, mild MR and moderate/serve MR according to MR occurred. All patients were clinically followed for 3-year to collect major adverse cardiac and cerebrovascular events (MACCEs), comprising all-cause death, nonfatal myocardial infarction (MI), rehospitalization for angina, rehospitalization for heart failure (RHF), and stroke. Cox regression models were employed to analyze the association between MR and 3-year clinical outcomes after adjusting for various confounding factors.

Results: Among the 6940 patients, 2871 (41.35%) exhibited no MR, 3681 (53.04%) had mild MR, and 388 (5.59%) had moderate/severe MR. The cumulative 3-year incidence of MACCEs was 19.21% overall, with rates of 15.26%, 20.37%, and 37.37% in the no MR, mild MR, and moderate/severe MR groups, respectively (log-rank p < 0.001). Kaplan-Meier survival curves of MR with all-cause death and RHF were also plotted (log-rank p < 0.001). After controlling confounding variables completely, we found that moderate/severe MR compared to none MR was found to be significantly associated with 3-year MACCEs [hazard ratio (HR) = 1.83; 95% confidence interval (CI) = 1.21-2.77; p = 0.0042], all-cause mortality (HR = 3.11; 95% CI = 1.75-5.50; p=0.001) and RHF (HR = 1.69; 95% CI = 1.09-2.62; p=0.019) through Cox proportional hazards regression models.

Conclusion: MR significantly predicted 3-year clinical outcomes in AMI patients undergoing PCI, highlighting the need for physicians to prioritize MR assessment in clinical practice.