742-5 Population Trends In Emergency Coronary Artery Bypass Graft Surgery

In a population-based registry of all Minneapolis–St. Paul residents who had coronary artery bypass graft (CABG) surgery, emergency CABG surgery (ECS) as a proportion of the total surgery steadily increased from 2.4% in 197074 to 12% in 1985–90. Operative mortality (OM, death within 30 days of CABG surgery) for ECS was significantly higher than OM for elective and urgent CABG surgery (odds ratio, OR=2.6). To understand the factors associated with ECS and the changes in these factors over time, the medical charts of 3,059 patients (814 women) randomly selected from 19,316 CABG surgery cases from 1970 to 1990 were reviewed. ECS cases (n = 264) were those described as emergent by the cardiologist or surgeon, or surgeries following cardiac arrest, immediately post infarction or within 24 hours of a cardiac procedure. Significant predictors of ECS were progressive/unstable angina (OR = 5.4), myocardial infarction (MI) within 30 days prior to CABG surgery (OR = 5.0), NYHA functional class III/IV (OR = 3.4), female gender (OR = 1.7). later year of CABG surgery (OR = 1.7), history of prior MI (OR = 1.61. moderate to severe left ventricular dysfunction (OR = 1.4), and increasing age (OR = 1.03). Factors that did not predict ECS included history of previous CABG surgery, history of diabetes, left ventricular aneurysm, left main coronary artery (LMCA) disease and increasing number of diseased vessels. In 1985–90, undergoing percutaneous transluminal coronary angio-plasty (PTCA) during the same hospitalization was highly predictive of ECS (OR 20.6,13.1–32.3).From 1970 to 1990 patients undergoing ECS showed increasing proportions of recent MI (30% vs. 50%; p = 0.02). increasing age (56 vs. 65 years; p<0.001). increasing number of diseased vessels (2.0 vs. 2.2; P<0.001), and decreasing LMCA disease (45% vs. 19%; p = 0.06). There were no significant trends in functional class, anginal status, or left ventricular dysfunction.We conclude that ECS is increasingly used on severely ill patients and those with failed PTCA. Mortality with ECS remains high