USE OF CARDIAC PROCEDURES AND OUTCOMES IN ELDERLY PATIENTS WITH MYOCARDIAL-INFARCTION IN THE UNITED-STATES AND CANADA

Background Acute myocardial infarction is a leading cause of morbidity and mortality in the United States and Canada. We performed a populat ion-based study to compare the use of cardiac procedures and outcomes after acute myocardial infarction in elderly patients in the two count ries. Methods We compared the use of invasive cardiac procedures and t he mortality rates among 224,258 elderly Medicare beneficiaries in the United States and 9444 elderly patients in Ontario, Canada, each of w hom had a new acute myocardial infarction in 1991. Results The U.S. pa tients were significantly more likely than the Canadian patients to un dergo coronary angiography (34.9 percent vs. 6.7 percent, P < 0.001), percutaneous transluminal coronary angioplasty (11.7 percent vs. 1.5 p ercent, P < 0.001), and coronary-artery bypass surgery (10.6 percent v s. 1.4 percent, P < 0.001) during the first 30 days after the index in farction. These differences in the use of cardiac procedures narrowed but persisted through 180 days of follow-up. The 30-day mortality rate s were slightly but significantly lower for the U.S. patients than for the Canadian patients (21.4 percent vs. 22.3 percent, P = 0.03). Howe ver, the one-year mortality rates were virtually identical (34.3 perce nt in the United States vs. 34.4 percent in Ontario, P = 0.94). Conclu sions Short-term mortality after an acute myocardial infarction was sl ightly lower in the United States than in Ontario, but these differenc es did not persist through one year of follow-up. The strikingly highe r rates of use of cardiac procedures in the United States, as compared with Canada, do not appear to result in better long-term survival rat es for elderly U.S. patients with acute myocardial infarction. (C) 199 7, Massachusetts Medical Society.