Perioperative acute myocardial infarction increases mortality following noncardiac surgery

Abstract

Objective: To provide insight into diagnosis, treatment, and prevention of perioperative myocardial infarction (PMI).

Design: The authors retrospectively analyzed PMI characteristics in patients undergoing noncardiac surgery and identified risk factors for death.

Setting: An affiliated teaching hospital with about 1500 beds.

Participants: The authors screened electronic medical records and retrospectively analyzed clinical data from 117,856 patients who underwent noncardiac surgery during the period from August 2003 through June 2011.

Interventions: Patients were divided into two groups based on survival at 30 days after PMI.

Measurements and main results: PMI was reported in 61 patients, for an overall incidence rate of 5.2 per 10,000. PMI incidence increased significantly with age, with a rate of 0.97 per 10,000 for the 45- to 60-year-old group, and increasing to a rate of 40.4 per 10,000 for the>75-year-old group (p<0.001). The mortality rate of non-PMI patients (n = 117,795) was 0.32%, whereas the mortality rate for the 61 PMI patients was 36.1% (p<0.001). PMI occurred acutely (within 48 to 72 hours of surgery) in the majority of patients (78.7%), and only 18% of these patients complained of chest pain. The majority of patients who suffered PMI had non-ST segment elevation acute myocardial infarction (78.7%). By multiple logistic regression analysis, lack of anticoagulation/antiplatelet therapy and cardiogenic shock were independent risk factors for death in PMI patients (p = 0.001 for both).

Conclusions: PMI incidence increased significantly with advanced age. PMI increased mortality following non-cardiac surgery. The independent risk factors for death in PMI patients following noncardiac surgery were lack of anticoagulation/antiplatelet therapy and cardiogenic shock.

Keywords: mortality; noncardiac surgery; perioperative acute myocardial infarction; survival.