Effect of preoperative angina pectoris on cardiac outcomes in patients with previous myocardial infarction undergoing major noncardiac surgery (data from ACS-NSQIP)

Abstract

The impact of preoperative stable angina pectoris on postoperative cardiovascular outcomes in patients with previous myocardial infarction (MI) who underwent major noncardiac surgery is not well studied. We studied patients with previous MI who underwent elective major noncardiac surgeries within the American College of Surgeons-National Surgical Quality Improvement Program (2005 to 2011). Primary outcome was occurrence of an adverse cardiac event (MI and/or cardiac arrest). Multivariable logistic regression models evaluated the impact of stable angina on outcomes. Of 1,568 patients (median age 70 years; 35% women) with previous MI who underwent major noncardiac surgery, 5.5% had postoperative MI and/or cardiac arrest. Patients with history of preoperative angina had significantly greater incidence of primary outcome compared to those without anginal symptoms (8.4% vs 5%, p = 0.035). In secondary outcomes, reintervention rates (22.5% vs 11%, p <0.001) and length of stay (median 6-days vs 5-days; p <0.001) were also higher in patients with preoperative angina. In multivariable analyses, preoperative angina was a significant predictor for postoperative MI (odds ratio 2.49 [1.20 to 5.58]) and reintervention (odds ratio 2.40 [1.44 to 3.82]). In conclusion, our study indicates that preoperative angina is an independent predictor for adverse outcomes in patients with previous MI who underwent major noncardiac surgery, and cautions against overreliance on predictive tools, for example, the Revised Cardiac Risk Index, in these patients, which does not treat stable angina and previous MI as independent risk factors during risk prognostication.