Effects of myocardial infarction on perioperative cardiac complications.

Of 1104 consecutive noncardiac operations on 981 patients using general anesthesia, 63 were performed on 53 patients who had had a previous myocardial infarction. Patients with a previous infarct were compared to those with no prior infarct to determine the influence of a previous infarct on perioperative cardiac complications. Two of the 53 patients with a previous myocardial infarction (3.8%) had perioperative myocardial infarction, compared to 0.4% (4/928) of patients with no prior history of myocardial infarction (P less than 0.05). Ventricular tachycardia (P less than 0.05) and cardiac death (P less than 0.01) were more frequent in patients with a previous myocardial infarction compared to those with no prior infarct. All patients with a previous myocardial infarction who developed cardiac complications underwent vascular procedures (P less than 0.005) and were over 77 years of age. The two patients who reinfarcted experienced intraoperative hypotension (P less than 0.05). Fourteen of the 53 patients with a history of a myocardial infarction (26.4%) had previous coronary artery bypass surgery; no perioperative cardiac complications occurred in these patients.