[Results and prognostic significance of echocardiography-dobutamine + atropine test in recent non-Q wave myocardial infarction].

BACKGROUND

Patients with non-Q wave myocardial infarction (NQ AMI) are usually considered to have an increased risk of recurrent ischemic events and reinfarction. We wished to assess whether dobutamine stress echocardiography with the addition of atropine (DOB-E + ATRO) can detect jeopardized myocardium after a recent NQ AMI and to assess the prognostic significance of this test in a group of patients with a first uncomplicated NQ AMI:

METHODS AND RESULTS

Fourty-one consecutive patients (38 men, mean age 52 +/- 9 years, 31 anterior, 68% treated with thrombolysis) underwent low and high-dose DOB-E (from 5 to 40 mcg/kg/min); ATRO was added in 14/41 (34%) patients. A significant deterioration of wall motion in the infarcted region (IR) indicative of residual myocardial ischemia was present in 36/41 patients (88%). Significant electrocardiographic changes and angina developed in 61% and 32% of patients, respectively. Coronary angiography was performed in 30/41 patients (73%) and showed 1-vessel coronary artery disease (CAD) in 70% of cases, multivessel CAD in 23% of cases and no significant CAD in 7% of patients. Three patients were lost at follow-up and 10 other patients were excluded from the analysis because a revascularization procedure was performed during diagnostic angiography. On a mean follow-up period of 9.5 +/- 9 months, the incidence of coronary events (re-infarction, recurrent angina, revascularization procedures) was higher (15/36 vs 1/5, 42% vs 20%) in patients with a DOB-E + ATRO positive test (1 reinfarction, 9 recurrent angina, 5 revascularized) than in those with a negative test (1 recurrent angina).

CONCLUSIONS

DOB-E + ATRO early after a first uncomplicated NQ AMI documents the presence of myocardial ischemia in the IR in the great majority of patients. A positive DOB-E + ATRO was found to be associated with a higher incidence of cardiac events at follow-up, but the results of this non prospective study (high sensitivity but low specificity and predictive value for cardiac events at follow-up) suggest to utilize with caution this test for risk stratification of patients with recent NQ AMI until prospective and larger studies are performed.