A retrospective study was undertaken at three hospitals of 196 patients who underwent an operative procedure as long as 60 days after radionuclide determination (multiple uptake gated acquisition scan [MUGA]) of left ventricular ejection fraction (LVEF). Cardiac related mortality rates were 2.2 per cent among patients in group 1, LVEF greater than or equal to 55 per cent; 5.4 per cent in group 2, LVEF 36 to 54 per cent, and 19.5 per cent in group 3, LVEF less than or equal to 35 per cent (p less than 0.005). Statistically significant correlation between MUGA-derived LVEF and cardiac related mortality was found in veteran patients undergoing noncardiac surgical procedures (both vascular and nonvascular). There was no correlation between MUGA-derived LVEF and postoperative cardiac related mortality in cardiac surgical patients. A preoperative American Society of Anesthesiologists Physical Status Evaluation classification of IV or a preoperative pulmonary capillary wedge pressure of 20 centimeters of water or greater also predicted an increased risk of postoperative cardiac death. We advise preoperative MUGA scans for all patients in whom the results of preoperative history or physical examination suggest compromised ventricular function. We also advise pulmonary arterial catheter hemodynamic monitoring during the perioperative period for all patients with a preoperative MUGA-derived LVEF of less than or equal to 35 per cent.