Predictors of Surgical Mortality in Patients Undergoing Direct Myocardial Revascularization

This study examines preoperative exercise, hemodynamic, and quantitative angiocardiographic variables as predictors of surgical mortality in the first 160 patients operated from this hospital. Of these, 138 (86%) had technically adequate quantitative left ventricular angiocardiography and 122 (76%) maximal treadmill exercise tests. Over-all surgical mortality was 4.4% (7/160). Mean age, functional class, functional aerobic impairment (FAI)— a measure of exercise limitation, stroke volume, cardiac index, and severity of coronary disease were similar in survivors and operative deaths. End-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular end-diastolic pressure (LVEDP) were significantly increased and ejection fraction significantly reduced in those who died versus the survivors. Functional class, FAI ≥ 55%, ST response to exercise, LVEDP > 13 mm Hg, cardiac index, stroke volume < 30 ml/m2, ejection fraction > 45%, ESV ≥ 45 ml/m2, or coronary score could not be demonstrated to be predictive of operative mortality. However, surgical mortality was significantly increased in those patients with EDV ≥ 103 ml/m2 (4/21 = 19%; P = 0.011), those with ejection fraction ≤ 33% (3/9 = 33%; P = 0.006), and those with LVEDP ≥ 18 mm Hg (3/16 = 19%; P = 0.034). Only those parameters relating to left ventricular performance were found to be predictive of operative mortality.