Prognosis of patients with a recurrent acute myocardial infarction before and in the reperfusion era - A national study

Background: Patients with recurrent acute myocardial infarction (AMI) are at increased risk for morbidity and mortality. We compared the outcome of patients with recurrent AMI hospitalized in coronary care units in the prereperfusion and reperfusion eras. Methods: The study population comprised 2 large-scale cohorts with recurrent AMI: (1) 1415 (24%) of 5839 consecutive patients with AMI hospitalized in 1981 to 1983 (Secondary Prevention Reinfarction Israeli Nifedipine Trial [SPRINT] Registry) and (2) 1093 (25%) of 4317 patients with AMI from three national surveys performed in 1992 to 1996. Results: Patients in the 1990s had significantly lower rates of heart failure and cardiogenic shock. The 7-day mortality declined from 18% in 1981-1983 to 10% in 1992-1996 (adjusted odds ratio [OR] 0.57 [0.44-0.75]), the 30-day mortality rate from 26% to 16% (OR 0.56 [0.44-0.71 ]), and the 1-year mortality rate from 39% to 26% (adjusted hazard ratio [HR] 0.64 [0.54-0.75]), respectively. In the 1992-1996 cohort, the adjusted risk of 7-day, 30-day, and 1-year mortality for patients with recurrent AMI treated with thrombolysis in comparison to patients without thrombolysis was OR 1.69 (1.07-2.65), 1.51 (1.03-2.23), and HR 1.18 (0.90-1.55), respectively. The mortality rate among patients treated with early percutaneous transluminal coronary angioplasty/coronary artery bypass grafting was 3% versus 12% at 7 days (OR 0.36 [0.16-0.73]), 7% versus 18% at 30 days (OR 0.45 [0.25-0.77]), and 16% versus 29% at 1 year (HR 0.64 [0.46-0.96]), in comparison to patients without revascularization. Conclusion: The prognosis of patients with recurrent AMI improved significantly during the reperfusion era. Although thrombolysis may have a limited therapeutic effect among patients with recurrent AMI, an interventional approach seems more appropriate when indicated. A randomized trial of thrombolysis versus early revascularization is needed in patients with recurrent AMI.