In recent years, increasing evidence has pointed to the potential of dipyridamole stress echocardiography as a fast, effective, inexpensive method of risk stratification after an acute myocardial infarction. A very early stratification by this test could improve the patient's management and reduce the duration of in-hospital stay, and, thus, the costs. Two-hundred and fifty-one consecutive patients (208 male, age 58 +/- 11) with a two-dimensional echocardiogram of good technical quality underwent a dipyridamole echocardiographic test (DET) 70 +/- 6 h after an acute myocardial infarction. Criterion for positivity was the identification of a transient regional asynergy that was absent or of a lower degree in the baseline examination. Positivity was defined as 'at low-dose' or 'at high-dose' if the asynergy was detected before or after the 8th min of a drug infusion. All tests were performed without any major side effects. DET was positive in 149 (59%) and negative in 102 (41%) patients. During the hospital stay, cardiac events (death, reinfarction, angina) occurred in 52/251 patients: in 49/149 with a positive and in 3/102 with a negative test (sensitivity 94%, negative predictive value 97%, P < 0.00001). Severe events (death and reinfarction) occurred in 14/251: in 12/149 with a positive DET and in 2/102 with a negative DET (sensitivity 86%; negative predictive value: 98%; P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)