PEROPERATIVE MYOCARDIAL-INFARCTION AND MY OCARDIAL-ISCHEMIA IN NONCARDIAC SURGERY - PREVALENCE AND PREDICTIVE FACTORS

BACKGROUND: The decrease in the prevalence of infarction in the popula tion has not been accompanied by a reduction in postinfarct mortality, particularly in the population segment which does not present major s ymptom of coronary disease. The aim of the present study was to determ ine the incidence and predictive factors of cardiac complications in p atients undergoing non cardiac surgery. METHODS: Eight hundred seventy -five patients undergoing elective surgery from May 1990-1991 had some of the following criteria: history of heart disease, major surgery, a nd medical risk other than cardiac. A sample of 328 patients was selec ted to whom an ECG an CK-MB isoenzyme test were performed on admission . every 8 h, and at the second arid third days. Infarction or ischemia were diagnosed by electrocardiographic and enzymatic criteria Minimum follow up was 72 hours. RESULTS: IAM was diagnosed in 10 cases (3%, c onfidence interval 95%, 2 to 4%) and ischemia in 47 cases (14%, CI 95% , 11 to 18%) Operative mortality of cardiac origin was 4% (CI 95%, 2 t o 6%). Arrhythmia not preoperatively present was detected in 11%, hemo dynamic instability in 25%, and sinusal tachycardia in 21%. Other comp lications were: abdominal 12%, respiratory 14%, neurologic 6% and rena l 4%. The appearance of cardiac complications was related with: ASA cl assification (p < 0.05), previous history of heart disease (p < 0.01), cardiovascular drug administration (p < 0.01) and changes in preopera tive electrocardiogram (p < 0.001). CONCLUSION: The present study sugg ests that patients with changes of the ST-T segment in the preoperativ e ECG should undergo examination to determine the degree of cardiac in volvement. A strict peroperative hemodynamic control may reduce the pr evalence of cardiac complications in those patients at high risk,