Role of coronary interventional procedures in improved postinfarction survival in the 1990s

The contribution of increased use of some-admission percutaneous coronary i nterventional procedures to recent,improvements in hospital survival of pat ients with acute myocardial infarction (AMI) remains unclear. Patients with International Classification of Diseases codes for AMI (code 410), who wer e admitted to the emergency coronary care unit and underwent an initial epi sode of treatment, were studied over the 9-year period 1990 to 1998 (n = 2, 628). Three triennia between 1990 and 1998 were compared, Trends in risk, t he use of procedures, and hospital outcomes were analyzed. Hospital mortali ty was 33% lower (p <0.02) in the third triennium (5.8%) than in the earlie r 2 triennia (8.7%), equivalent to an absolute reduction of 29 hospital dea ths/1,000 patients treated. The lower hospital mortality was not due to: (1 ) shorter hospital stays (reduction in mortality was primarily in the first 3 hospital days), (2) treatment of lower risk subjects (a risk score based on age, gender, and presence of diabetes increased between the first and t hird triennia), or (3) use of in-hospital interventional procedures (althou gh the use of percutaneous coronary intervention more than doubled in the t hird triennium, most procedures were performed in patients with a 1% risk o f hospital death). We conclude from this study that there has been a substa ntial improvement over a 9-year period in early case fatality after AMI, bu t that this cannot be attributed to the increased use of in-hospital corona ry interventions, which were largely performed on low-risk patients. <(c)> 2001 by Excerpta Medica, Inc.