P44 IMPROVEMENT OF THE LEFT VENTRICULAR CONTRACTILE RESERVE IN PATIENTS UNDERGOING MITRAL VALVE PLASTIC CARDIAC SURGERY

Abstract Mitral Regurgitation (MR) is a clinical condition characterized by a high morbidity and mortality in severe or moderate forms complicated by hemodynamic instability, that often finds a solution only in the reparative surgical treatment. MR is often caused the presence of myxomatous degeneration that affects one or more structures of the valve apparatus, causing the prolapse of one or both leaflets. Surgical treatment can improve the hemodynamic parameters and consequently the prognosis of the patients, even though there is not still data concerning the myocardial contractile reserve. The aim of the study was to evaluate the effect of MR reparative surgery on the left ventricular contractile reserve during physical stress echocardiography. We enrolled 12 patients, 8 females and 4 males, affected by MR candidate to cardiac surgery. We performed a physical stress–echo test by using the ABCDE protocol suggested by the Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI), before and after approximately 12 weeks from cardiac surgery. After each test, the prognostic score deriving from the sum of the ABCDE criteria was calculated; in addition, we measured the left ventricular contractile reserve (C parameter of the score) that represents a parameter of the force deriving from the hemodynamic changes during the test. In all patients we observed a significant improvement in the ABCDE prognostic score after cardiac surgery (3.89 + 0.43 vs 3.18 + 0.37; p = 0.002). There were no significant changes in ejection fraction, indexed left atrial volume, wall motion score index–WMSI (A parameter), coronary reserve (D parameter), and heart rate reserve (E parameter). The most relevant data concerns the increase in the left ventricular contractile reserve at 3 months after cardiac surgery (1.77 mmHg/ml vs 2.44 mmHg/ml, p