Stress echocardiographic results predict risk of reinfarction early after uncomplicated acute myocardial infarction: Large-scale multicenter study

Objectives. This study sought to assess the value of dipyridamole echocardiography in predicting reinfarction in patients evaluated early after uncomplicated acute myocardial infarction. Background. The identification of future nonfatal reinfarction seems an elusive target for physiologic testing. However, large sample population is needed to detect minor differences in phenomen with low event rate. Methods. We assessed the value of dipyridamole echocardiography in predicting reinfarction in 1,080 patients (mean [±SD] age 56 ± 9 years; 926 men, 154 women) evaluated early (10 ± 5 days) after uncomplicated acute myocardial infarction and followed up for 14 ± 10 months. Results. Submaximal studies due to limiting side effects occurred in 14 patients (1.3%); these test results were included in the analysis. Results of dipyridamole echocardiography were positive in 475 patients (44%). During follow-up, there were 50 reinfarctions: 45 nonfatal, 5 fatal (followed by cardiac death ≤4 days after reinfarction). Reinfarction (either nonfatal or fatal) occurred in 30 patients with positive and 20 with negative results (6.3% vs. 3.3%, p < 0.01). Nonfatal reinfarction occurred in 25 patients with positive and 20 with negative results (5% vs. 3.3%, p < 0.05). Reinfarction was fatal in 5 of 30 patients with positive and in none of 20 with negative results (16.6% vs. 0%, p = 0.07). The relative risk of reinfarction was 1.9. Conclusions. Dipyridamole echocardiographic positivity identifies patients evaluated early after uncomplicated acute myocardial infarction at higher risk of reinfarction, especially fatal reinfarction.