The value of the radionuclide angiogram in the prediction of perioperative myocardial infarction in patients undergoing lower extremity revascularization procedures.

To better define the group of patients at high risk of myocardial infarction (MI) and death associated with lower extremity revascularization procedures, resting gated blood pool studies were obtained in 100 such patients before surgery and results were correlated with the prevalence of perioperative MI. The results indicated that three patient groups could be distinguished on the basis of cardiac ejection fraction. Group I (n = 50) had preoperative ejection fractions ranging from 56% to 83%. None of the patients in group I suffered an acute perioperative MI. Group II (n = 42) comprised patients with ejection fractions ranging from 36% to 55%. There was a 19.0% prevalence of MI in group II, with one cardiac death. Group III included eight patients with ejection fractions ranging from 26% to 35%. There was a 75% prevalence of perioperative MI in these patients, with one cardiac death. All perioperative MIs occurred within the first 48 hr after surgery. Statistical analysis demonstrated a significantly higher prevalence of perioperative MI in patients with gated pool ejection fractions of 35% or less compared with the prevalence in patients with one or more of the other widely used clinical signs of increased cardiac operative risk (p less than .02).