Comparison of outcome of primary PTCA for acute myocardial infarction in patients younger and older than 70 years of age

BACKGROUND: The Primary Angioplasty in Myocardial infarction Study Group reported that the benefit of primary PTCA was observed mainly among patients who were classified as "not low risk" including those over age 70, with anterior infarction and heart rate > 100 bpm. The present study compares procedural success rate and in-hospital and one-month clinical outcome of primary PTCA in acute myocardial infarction patients < 70 and > or = 70 years of age. METHODS AND RESULTS: During 1995 121 patients with acute myocardial infarction underwent primary PTCA within 6 hours of symptoms onset or within 24 hours in case of evidence of ongoing ischemia. Eighty-two patients (Group I) were < 70 (mean age 56 +/- 9) and 39 patients (Group II) were > or = 70 (mean age 75 +/- 3). In group II there was a trend, although not significant, toward a higher prevalence of prior angina and infarction. Multivessel disease was more frequent in group II than in group I (69% vs 48%; p = 0.041). Ejection fraction was markedly depressed in both groups (38 +/- 10% in group I vs 34 +/- 11% in group II). Ejection fraction < or = 30% and shock on admission were more frequent in group II (39% vs 15% and 36% vs 21%, respectively). Optimal angiographic success (< or = 30% stenosis associated with TIMI grade 3 flow) was achieved in 77% of group II and in 98% of group I (p = 0.00059). The in-hospital mortality rate was 26% in group II and 1.2% in group I (p = 0.000042). Shock on admission and PTCA failure predicted high mortality rates. There was no difference between the two groups as regards to non-fatal reinfarction, recurrent ischemia, life-threatening arrhythmias, severe heart failure, revascularization procedures. There were no strokes. At one-month follow-up, recurrence of ischemia or positive response to stress test were more frequent in group II (24% vs 8%; p = 0.039). CONCLUSIONS: In patients with acute myocardial infarction < 70 years of age primary coronary angioplasty is associated with low rates of mortality and cardiac events. Mortality rate remains high in patients over age 70, especially when shock is present on admission or PTCA falls.