Risk scores for predicting mortality after surgical ventricular reconstruction for ischemic cardiomyopathy: Results of a Japanese multicenter study

Objectives: Surgical ventricular reconstruction has been believed to be beneficial for those with ischemic cardiomyopathy. However, the effectiveness of surgical ventricular reconstruction was not proved by a large-scale trial, and no report has clearly demonstrated the exact indications and limitations of surgical ventricular reconstruction. The purpose of this study was to elucidate predictive factors of mortality after surgical ventricular reconstruction and to develop a prognostic model by calculating risk scores. Methods: The study subjects were 596 patients who underwent surgical ventricular reconstruction for chronic ischemic heart failure in 11 Japanese cardiovascular hospitals between 2000 and 2010. Potential predictors of postoperative mortality were assessed using the Cox proportional hazards model, and a risk score was calculated. Results: Forty-one patients died before discharge, and 81 patients died during a mean follow-up time of 2.9 years. Four independent predictors of mortality were identified: age, Interagency Registry for Mechanically Assisted Circulatory Support profile, left ventricular ejection fraction, and severity of mitral regurgitation. Each variable was assigned a number of points proportional to its regression coefficient. A risk score was calculated using the point scores for each patient, and 3 risk groups were developed: a low-risk group (0-4 points), an intermediate-risk group (5-6 points), and a high-risk group (7-12 points). Their 3-year survivals were 93%, 81%, and 44%, respectively (log-rank P < .001). Harrell's C-index of the predictive model was 0.69. Conclusions: A simple prognostic model was developed to predict mortality after surgical ventricular reconstruction. It can be useful in clinical practice to select treatment options for ischemic heart failure.