Low-dose dobutamine testing using contrast left ventriculography in the same session as coronary angiography predicts the improvement of left ventricular function after coronary angioplasty in postinfarction patients

The role of percutaneous transluminal coronary angioplasty (PTCA) in the su bacute or chronic phases of myocardial infarction remains controversial. Th is study investigates the usefulness of dobutamine contrast left ventriculo graphy in a single session with coronary angiography for predicting the imp rovement of ventricular function after PTCA. The study group consisted of 3 0 patients in whom a contrast left ventricular angiogram and PTCA were perf ormed after a first myocardial infarction. The centerline method was used t o calculate dysfunction extent at baseline and its variation during dobutam ine infusion at 7.5 mu g/kg/min; contractile reserve was defined as a signi ficant (greater than or equal to 15%) reduction of dysfunction extent. A se cond ventricular angiogram was performed 6 months later in all patients. Ab normal wall motion extent decreased at 6 months after PTCA (84 +/- 21% vs 7 0 +/- 29%, p = 0.0001). Wall motion improvement after PTCA correlated with the response to dobutamine (r = 0.54, p = 0.002). Ten patients showed a sig nificant reduction (greater than or equal to 15%) of dysfunction extent at 6 months; dobutamine testing had a 80% sensitivity, 84% specificity, 67% po sitive predictive value, and 89% negative predictive value in detecting reg ional function improvement. In the subgroup of 21 patients without restenos is, both the correlation between dysfunction improvement after PTCA and res ponse to dobutamine (r = 0.72, p = 0.0001) and the accuracy of dobutamine t esting (sensitivity 88%, specificity 92%, positive predictive value 88%, an d negative predictive value 92%) increased. The election fraction significa ntly increased (>5%) after PTCA in 6 patients; dobutamine testing had a 67% sensitivity, 74% specificity, 44% positive predictive value, and 88% negat ive predictive value in predicting the increase in the election fraction. I n the subgroup without restenosis the improvement of the election fraction correlated with the response to dobutamine (r = 0.63, p = 0.007), and the s ensitivity of dobutamine testing was 80%, specificity 83%, positive predict ive value 67%, and negative predictive value 91%. In conclusion, dobutamine contrast left ventriculography testing in the same session as coronary ang iography predicts regional function and ejection fraction improvement after PTCA in postinfarction patients, particularly when restenosis does not dev elop. (C)1999 by Excerpta Medica, Inc.