Utility of stress echocardiography in selecting the optimal mitral valve procedure in patients with severe ischemic mitral regurgitation undergoing coronary artery bypass grafting

Abstract

Severe functional ischemic mitral regurgitation (FIMR) considerably worsens the prognosis of patients after myocardial infarction. The complex pathomechanism of FIMR and its dynamic nature make it difficult to develop effective therapeutic methods. The aim of the study was to prospectively assess a diagnostic strategy based on stress echocardiography in referring patients with severe FIMR for appropriate surgical procedure: coronary artery bypass grafting alone (CABGa) or CABG with mitral annuloplasty (CABGma) or replacement (CABGmr). A prospective analysis included 42 patients (23 women, 19 men) aged 67 ±12 years with severe FIMR after myocardial infarction, scheduled for CABG. In each patient, mitral valve morphology, left ventricular function, FIMR degree as assessed by the effective regurgitation orifice area (severe ≥ 20 mm²), myocardial viability, and mitral deformation indexes were assessed prior to surgery. Based on clinical assessment and rest and stress echocardiography parameters, patients were referred for CABGa (group 1; n = 6), CABGma (group 2; n = 27), or CABGmr (group 3; n = 9). In all study groups, no differences in clinical and echocardiographic results were observed during a 12-month follow-up. A significant improvement was reported in the majority of patients regardless of the surgical procedure. Early (30-day) mortality in the whole study population was 11.9% (n = 5). Survival at 12 months was 100%, 81.5%, and 77.8% for groups 1, 2, and 3, respectively (P = 0.3). In all study groups, a statistically significant FIMR reduction was observed in a 12-month follow-up: small, moderate, and severe FIMR was observed in 29 (83%), 5 (14%), and 1 (3%) surviving patient, respectively. Reverse left ventricular remodeling was observed in 83% of the patients in group 1, 63.7% in group 2, and 100% in group 3 (statistically nonsignificant difference). The presented diagnostic strategy, based on stress echocardiography, may facilitate the process of choosing a suitable cardiac surgical procedure for patients with severe FIMR.