Predictive Value of Biphasic Response During Dipyridamole Echocardiography Test in the Low-risk Group of Patients After Acute Myocardial Infarction

To investigate whether biphasic response during dipyridamole echocardiography test (DET), which represents viable but potentially ischemic myocardium in the infarcted region, affects prognosis of patients after uncomplicated acute myocardial infarction, we performed high-dose DET in 80 consecutive patients younger than 65 years with first acute myocardial infarction and preserved left ventricular function. Patients were followed up for 27 ± 12 months for new coronary events. According to DET results all patients were classified into 4 groups: group 1 consisted of 20 patients with biphasic response; group 2 included 14 patients with sustained improvement in regional contractility; group 3 consisted of 24 patients showing no change in contractility; and group 4 included 22 patients with worsening response. Cumulative survival free of total coronary events was significantly lower in group 1 patients compared with all other groups (P < .05). By multivariate Cox analysis biphasic response was the strongest independent predictor of stable angina pectoris (odds ratio = 12.1, P = .0002), followed by hyperlipoproteinemia (odds ratio = 5.9, P = .006). On the other hand, development of acute coronary syndromes could not have been predicted by actual clinical or DET parameters.