Angina and persistent exercise thallium defects: independent risk factors in elective vascular surgery
EO McFalls,
KM Doliszny,
F Grund,
E Chute,
and
E Chesler
Department of Cardiology, Veterans Affairs Hospital, Minneapolis, Minnesota 55417.
OBJECTIVES. In this study, we assessed the utility of exercise thallium-201 scintigraphy and other clinical factors in predicting perioperative cardiac complications in patients undergoing elective vascular surgery. BACKGROUND. The risk of cardiac complications among such patients is very high. METHODS. The study group comprised 116 men (mean age 67 years). Fifty patients (43%) had a history of coronary artery disease, including angina pectoris in 26 (22%), myocardial infarction in 32 (28%) and coronary artery bypass surgery in 19 (16%). RESULTS. There were a total of 22 perioperative myocardial infarctions (18.9%), including 2 cardiac deaths (1.7%). A significantly greater proportion (p < 0.05) of patients with than without perioperative complications had a history of coronary artery disease (77% vs. 35%), angina (59% vs. 14%), prior myocardial infarction (50% vs. 22%), abnormal electrocardiogram (68% vs. 40%) and abnormal exercise thallium test (75% vs. 47%). The patient group with complications also had a significantly lower mean rest ejection fraction (45 +/- 3% vs. 55 +/- 2%, p < 0.005). Independent predictors of complication, as determined by straight logistic regression, were angina and fixed thallium defects after exercise. CONCLUSIONS. Our data indicate that angina and the presence of fixed thallium defects after exercise are independent predictors of cardiac risk in patients undergoing elective vascular surgery. These findings are compatible with other studies showing that nonredistribution on standard 3- to 4-h delayed studies cannot exclude viable myocardium at risk.
