The risk of major cardiovascular events in the postoperative period can reach up to 25%, particularly if there were CAD antecedents.

A prospective study in patients with CAD diagnosed by complementary examination (arteriography) or clinical history (MI, angina), monitored in the first 24 hours of the postoperative period, using the system of continuous electrocardiography monitoring (Holter^®) of three canals and myocardial injury markers (CPK, MB and troponin).

Initial inclusions involved seven (70%) male patients and three (30%) female patients; the age varied from 48 to 90 years, with an average of 66 years and a mode of 56 years. The APACHE varied score from 4 to 14 with a mode of 14, and the median risk of death was 5%. Three patients (30%) had antecedents of coronary artery bypass graft and three (30%) patients of angioplasty; four patients had recent coronary arteriography with injuries of up to 60% in up to two cases. Arrhythmias had been present in all the patients, being supraventricular extrasystole and supraventricular tachycardia in five (50%) patients and ventricular extrasystole in five (50%) patients. Three (30%) patients had presented silent myocardial ischemia with disturbances in the ST segment varying from 2.0 to 3.4 mm in at least two canals, with positive trooping in two (20%) patients, although an echocardiogram of stress with dobutamine (previous to surgery) was negatively affected in two of these patients. We did not have death occurrence, having only prolongation of hospital internment in the three patients with myocardial ischemia.

The occurrence of myocardial ischemia in patients with CAD can be a frequent event and, despite evaluation daily post surgery, must always rigorously be monitored.