Myocardial Performance Index as Predictor of Adverse Outcomes Following Mitral Valve Surgery

AIMS: We aim to determine whether the myocardial performance index, will be a good predictor of adverse outcomes following mitral valve surgery. METHOD: We prospectively measured pre-operative myocardial performance index in 22 consecutive patients, with moderate to severe mitral insufficiency, undergoing corrective mitral valve surgery. The primary endpoint was predefined as either peri-operative death or congestive heart failure. RESULTS: The primary endpoint occurred in nine patients. Five of the six patients with myocardial performance index >or=0.7 had primary endpoints. Chi-square testing demonstrated that the primary endpoint was significantly associated with advanced age (>or=70 years) and myocardial performance index >or=0.7 (P=0.003 and 0.01 respectively). There was a trend towards significant association of depressed left ventricle ejection fraction (left ventricle ejection fraction <or=40%) and the primary endpoint (P=0.09). Although left ventricle ejection fraction <or=40% was more sensitive in predicting the primary endpoint, it has lower specificity, accuracy and predictive values than myocardial performance index >or=0.7. CONCLUSION: Our results suggest that myocardial performance index is a potentially useful predictor of increased risk of peri-operative death or congestive heart failure, in patients with moderate-severe mitral insufficiency undergoing corrective mitral valve surgery. In conjunction with left ventricle ejection fraction, it may be helpful in the pre-operative prognostication of these patients.