Estimating postoperative left ventricular volume: Identification of responders to surgical ventricular reconstruction.

Abstract

The postoperative left ventricular end-systolic volume index and ejection fraction are benchmarks of surgical ventricular reconstruction but remain unpredictable. This study aimed to identify who could be associated with a higher long-term survival by adding surgical ventricular reconstruction to coronary artery bypass grafting than coronary artery bypass grafting alone (responders to surgical ventricular reconstruction). The subjects were 293 patients (median age, 63 years; 255 men) who underwent coronary artery bypass grafting for ischemic heart disease with left ventricular dysfunction in 16 cardiovascular centers in Japan. The relationships among surgical ventricular reconstruction, postoperative end-systolic volume index, ejection fraction, and survival were analyzed to identify responders to surgical ventricular reconstruction. Surgical ventricular reconstruction was performed in 165 patients (56%). The end-systolic volume index and ejection fraction significantly improved (end-systolic volume index, 91 to 64 mL/m²; ejection fraction, 28% to 35%) for all patients. The postoperative end-systolic volume index and ejection fraction were estimated, and surgical ventricular reconstruction was found to be significantly associated with both end-systolic volume index (14.5 mL/m² reduction, P < .001) and ejection fraction (3.1% increase, P = .003). During the median follow-up of 6.8 years, 69 patients (24%) died. Only the postoperative ejection fraction was significantly associated with survival (hazard ratio, 0.925; 95% confidence interval, 0.885-0.968), although this effect was limited to those with postoperative end-systolic volume index of 40 to 80 mL/m² in the subgroup analysis (hazard ratio, 0.932; 95% confidence interval, 0.894-0.973). Adding surgical ventricular reconstruction to coronary artery bypass grafting could reduce the mortality risk by increasing ejection fraction for those with a postoperative end-systolic volume index within a specific range. The postoperative end-systolic volume index could demarcate responders to surgical ventricular reconstruction, and its estimation can help in surgical decision making.