Background: The prognostic significance of early dobutamine echocardiography (DE) after successfully treated acute myocardial infarction (AMI) with primary coronary angioplasty (PTCA) is still unclear. Patients who respond to DE may have better left ventricular function improvement and possibly a better clinical outcome.
Aim: To assess whether early DE can predict spontaneous functional recovery in patients treated successfully with primary PTCA and whether responders to DE have a better clinical outcome.
Methods: DE (5 and 10 ug/kg/min) was performed in 110 consecutive patients (61+/-10 years) 4+/-1 days after successful primary PTCA (TIMI 3, stenosis <30%). Left ventricular ejection fraction (LVEF) and wall motion index (WMSI) were measured. Patients underwent clinical assessment and two-dimensional echocardiography at 3 and 6 months.
Results: In the DE responders (76 pts), LVEF increased significantly from 41%+/-9% at baseline to 47%+/-10% at 6 months (p<0.0001), whereas the improvement found in nonresponders (34 pts) was insignificant (from 36.3%+/-9% at baseline to 38.8%+/-10% at 6 months, p=0.4). The nonresponders to DE had a higher incidence of subsequent revascularisation (4/34 (11.8%) vs 3/76 (3.9%) p=0.12), reinfarction (5/34 (14.7%) vs 2/76 (2.6%), p=0.28) and death (3/34 (9%) vs 0/76 (0%), p=0.0086). The incidence of combined end-point (revascularisation, reinfarction and death) was significantly lower in the group of responders to early DE (p=0.03).
Conclusions: Early DE can precisely predict functional recovery and the extent of irreversibly damaged myocardium in patients with AMI in whom anterograde flow is fully restored. A positive response to early DE is associated with a better clinical outcome and prognosis.