Usefulness of dipyridamole-echocardiographic test to identify jeopardized myocardium after thrombolysis. Limited clinical predictivity of dipyridamole-echocardiographic test in convalescing acute myocardial infarction: correlation with coronary angiography.

A dipyridamole-echocardiographic test (DET) was carried out to find out how safe and useful it was in predicting clinical outcome and in identifying patients at risk. The test was performed in 107 asymptomatic patients early (5 to 8 days) after a first acute uncomplicated myocardial infarction managed with thrombolytic therapy. All patients were followed up for a mean of 15 months and 94 underwent coronary angiography. The test was considered positive if transient asynergy of contraction was newly detected either in the infarct and adjacent areas or in the remote zones; two subsets were studied, according to the dose of dipyridamole (0·56 or 0·84 mg . kg−1) needed to induce ischaemia. The test was accomplished satisfactorily in 96% of patients. Intra-inter-observer agreements were 88% and 91% respectively. The test also proved safe at the high infusion dose. During the follow-up period, two patients died, one experienced re-infarction and 12 (12%) developed recurrence of angina. DET was abnormal in 32 patients (adjacent and remote asynergy in 28 and four patients respectively) .18 had a critical and two a non-critical stenosis in the infarct-related vessel, and nine had an occluded artery with collateral distal flow. Multivessel disease was present in 11 patients considered positive, four in the remote and seven in the adjacent zones. However, 20 patients with negative DET results had multivessel disease. Of the positive DET patients, seven had angina. There were eight total events in the 71 negative DET patients, five of whom had multivessel disease. Abnormality was more pronounced in positive DET patients, but did not influence the outcome. The incidence of all cardiac events did not correlate with the DET results. However, the cumulative probability of events over a period of 18 months showed that a positive test was significantly more frequent in patients who developed recurrence of angina (P=0·01). Regional wall motion abnormality was far more frequent in the infarct-related area than in remote zones, indicating that DET is useful in detecting residual ischaemia of still viable myocardium even if it shows a limited value in predicting all cardiac events of post-infarction patients treated with thrombolysis.