The changing status of ejection fraction as a predictor of early mortality following surgery for acquired heart disease.

Several reports in the literature and our experience prior to 1974 support the thesis that operative risk in patients with acquired heart disease and poor ventricular function (as assessed by a biplane ejection fraction [EF] less than or equal to 0.40) was very significantly increased over the risk in patients with normal ventricular function. These results led to disagreement in the literature regarding the advisability of surgery in patients with poor ventricular function. Various EFs from less than 0.31 to less than 0.50 were suggested as contradicting elective surgery, while more aggressive groups recommended surgery in all patients with angina. Precise comparison of the results reported by different groups was not always possible because of the common reliance on single-plane right anterior oblique ventriculograms, which tend to underestimate EF and overestimate operative risk. Using biplane ventribulograms for accurate estimation of EF, we have demonstrated a significant reduction in 30-day operative risk to a clinically acceptable 3 percent (1/32) for single valve replacement and aortocoronary surgery patients with poor ventricular function (EF less than or equal to 0.40) during 1974. Considering the high risk of medically treated patients with reduced ventricular function, these results support further evaluation of surgical palliation for patients with valvular or coronary heart disease and reduced ventricular function.