Perioperative myocardial infarction in coronary artery disease patients and 'at-risk' for coronary artery disease patients undergoing non-cardiac surgery.

Varma, M K; Puri, G D; Chari, P; Verma, J S; Kohli, K K

Perioperative myocardial infarction in coronary artery disease patients and 'at-risk' for coronary artery disease patients undergoing non-cardiac surgery.

Date

1996-09-01

Authors

Abstract

BACKGROUND: Perioperative myocardial infarction (POMI) carries a high mortality and occurs more commonly in patients with a history of coronary artery disease (CAD). However, there are also other patients undergoing surgery who are 'at risk' for CAD but who do not have a history of infarction or angina. We compared the incidence of POMI in these two groups. METHODS: In a prospective study of 69 men and 39 women over 30 years of age undergoing non-cardiac surgery under general or regional anaesthesia, 56 had definite CAD and 52 were 'at-risk' for CAD. All these patients were followed up with serial postoperative electrocardiography and CK-MB isoenzyme analysis for the diagnosis of POMI. RESULTS: The POMI rate was 32% in definite CAD patients and 15% in patients 'at-risk' for CAD. Mortality in patients with POMI was 17% in those with CAD and 13% in those 'at-risk' for CAD. Perioperative myocardial infarction was maximal in the first 24 hours following surgery (77%). All the POMIs were painless. Anaesthesia techniques--whether regional or general--did not influence the incidence of POMI (Chi-square, p > 0.05). The type of drugs used in the treatment of CAD such as beta-blockers, calcium channel blockers and antiplatelet agents did not cause any difference in the incidence of POMI (Chi-square, p > 0.05). Patients who had either an intraoperative hypertensive episode, tachycardia, arrhythmias or ST-segment changes had a higher incidence of POMI (Chi-square, p > 0.05). The incidence of POMI was not lower in patients undergoing transurethral resection of the prostate compared to patients undergoing other types of non-cardiac surgery (Chi-square, p > 0.05). CONCLUSION: POMI occurs in one-third of patients with a history of CAD and one-sixth of those 'at-risk'. It carries a mortality of 17% and 13% respectively. Decisions to operate on such patients should be taken with caution.

Citation

Varma MK, Puri GD, Chari P, Verma JS, Kohli KK. Perioperative myocardial infarction in coronary artery disease patients and 'at-risk' for coronary artery disease patients undergoing non-cardiac surgery. National Medical Journal of India. 1996 Sep-Oct; 9(5): 214-7