Prevalence and Mortality of Moderate or Severe Mitral Regurgitation Among Patients Undergoing Percutaneous Coronary Intervention With or Without Heart Failure: Results From CIN Study With 28,358 Patients

AIM: This study investigated the prevalence and mortality associated with moderate or severe mitral regurgitation (MR) among patients undergoing percutaneous coronary intervention (PCI), with or without heart failure (HF). METHODS: We analyzed patients undergoing PCI without mitral valve surgery from the Cardiorenal ImprovemeNt (CIN) study (ClinicalTrials.gov NCT04407936). Patients without echocardiography to determine MR occurrence or lacking follow-up death data were excluded. Primary endpoints were 1-year and long-term all-cause mortality, with a median follow-up time of 5 years (interquartile range: 3.1–7.6). RESULTS: Of 28,358 patients undergoing PCI treatment [mean age: 62.7 ± 10.7; women: 6,749 (25.6%)], 3,506 (12.4%) had moderate or severe MR, and there was a higher rate of moderate or severe MR in HF group than non-HF group (28.8 vs. 5.6%, respectively). Regardless of HF conditions, patients with moderate or severe MR were older and had worse cardio-renal function and significantly increased 1-year mortality [adjusted hazard ratio (aHR): 1.82, 95% confidence interval (CI): 1.51–2.2], and long-term mortality [aHR: 1.43, 95% CI: 1.3–1.58]. There was no significant difference between patients with HF and those with non-HF (P for interaction > 0.05). CONCLUSION: One-eighth of the patients undergoing PCI had moderate or severe MR. Furthermore, one-third and one-seventeenth experienced moderate or severe MR with worse cardiorenal function in the HF and non-HF groups, and increased consistent mortality risk. Further studies should explore the efficacy of mitral interventional procedures for moderate or severe MR after PCI treatment, regardless of HF.