Background: Advanced age remains one of the principal determinants of mortality in patients with acute myocardial infarction (AMI).
Hypothesis: The aim of this study was to determine the in-hospital outcome of elderly (> 75 years) patients with AMI who were admitted to hospitals participating in the national MITRA (Maximal Individual Therapy in Acute Myocardial Infarction) registry.
Methods: MITRA is a prospective, observational German multicenter registry investigating current treatment modalities for patients presenting with AMI. All patients with AMI admitted within 96 h of onset of symptoms were included in the MITRA registry. MITRA was started in June 1994 and ended in January 1997. This registry comprises 6,067 consecutive patients with a mean age of 65 +/- 12 years, of whom 1,430 (17%) were aged > 75 years. Patients were compared with respect to patient characteristics, prehospital delays, early treatment strategies, and clinical outcome.
Results: In the elderly patient population, the prehospital delay was 210 min, which was significantly longer than that for younger patients (155 min, p = 0.001). Although the incidence of potential contraindications for the initiation of thrombolysis was almost equally distributed between the two age groups (8.7 vs. 8.2%, p = NS), elderly patients (> 75 years) received reperfusion therapy less frequently (35.9 vs. 64.6%) than younger patients. Mortality increased with advanced age and was 26.4% for all patients aged > 75 years. If reperfusion therapy was initiated, in-hospital mortality was 21.8 versus 28.9% in patients aged > 75 years (p = 0.001) and 29.4 versus 38.5% in patients aged > 85 years (p = 0.001).
Conclusion: In this registry, elderly patients with AMI had a much higher in-hospital mortality than that expected from randomized trials. In MITRA, the mortality reduction with reperfusion therapy was found to be highest in the very elderly patient population.