[At risk myocardium after acute infarct treated with fibrinolysis: assessment using exertion echocardiography and clinico-prognostic significance].
Several studies have been carried out on the role of exercise echocardiography for risk stratification after uncomplicated myocardial infarction. However, the diffusion of thrombolysis has entailed a remarkable change in the characteristics of these patients, with a major incidence of recurrent ischemic events or reinfarction in the follow-up. To test whether the predictive value of exercise echocardiography may be modified by thrombolytic treatment, we have studied 62 patients with acute myocardial infarction undergoing lytic therapy (Group A), compared to 153 conventionally-treated patients (Group B). All patients were asymptomatic at the time of the test, performed by cycloergometer 14 days after hospital admission. In 125 patients (47 Group A and 78 Group B) predischarge coronary angiography was performed. The exercise test showed a lower, but not significant, rate of positive tests in Group A patients (51.6 vs 58.8%). However, a positive test was more frequent in the homozonal area among patients who underwent thrombolytic therapy (50% of positive tests vs 18% in Group B; p < 0.001). Follow-up data (23 +/- 17 months) showed a higher but not significant rate of coronary events (cardiac death, reinfarction, severe angina, coronary bypass or angioplasty) in Group A patients with a positive test (62 vs 39% in Group B); however, in the subgroup with homozonal positive test, the event rate was much higher in Group A (77 vs 18% in Group B; p < 0.01). Furthermore, among patients with negative exercise test, coronary events were observed in 8% Group A and in 10% Group B patients. Therefore, our results show a higher percentage of homozonal exercise-induced ischemia with subsequent higher rate of coronary events in the thrombolyzed patients with respect to controls. This pattern is probably due to a higher rate of significant infarct-related residual stenosis, as coronary angiography have demonstrated. In conclusion, exercise echocardiography is useful in thrombolyzed patients, since it may better explore, rather than ECG, peri-necrotic areas.
Penco
M
M
Dipartimento di Medicina Interna e Sanità Pubblica, Università degli Studi, L'Aquila.
Romano
S
S
Vizza
C D
CD
Dagianti
A
A
Varveri
A
A
Sciomer
S
S
Dagianti
A
A
D017023:Coronary Angiography; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000188:drug therapy; D011379:Prognosis; D012189:Retrospective Studies; D015912:Thrombolytic Therapy; D016277:Ventricular Function, Left