COMPARISON OF MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY AND LOW-DOSE DOBUTAMINE STRESS ECHOCARDIOGRAPHY IN PREDICTING RECOVERY OF LEFT-VENTRICULAR FUNCTION AFTER CORONARY REVASCULARIZATION IN CHRONIC ISCHEMIC-HEART-DISEASE

Background Dobutamine stress echocardiography (DSE) and myocardial con trast echocardiography (MCE) can predict recovery of left ventricular function after myocardial infarction. DSE also has been shown to predi ct left ventricular functional recovery after revascularization in chr onic ischemic heart disease, whereas MCE has not been evaluated in suc h patients. This study was performed to compare DSE and MCE in the pre diction of left ventricular functional recovery after revascularizatio n in patients with chronic ischemic heart disease. Methods and Results MCE and DSE were performed in 35 patients with chronic coronary arter y disease and significant wall motion abnormalities (mean ejection fra ction, 0.36+/-0.09). Regional wall motion was scored by use of a 16-se gment model wherein 1=normal or hyperkinetic, 2=hypokinetic, 3=akineti c, and 4=dyskinetic. Each segment was evaluated for contractile reserv e by DSE and perfusion by MCE. Revascularization (coronary artery bypa ss graft [n=13] and percutaneous transluminal coronary angioplasty [n= 10]) was successful in 23 patients. Follow-up echocardiograms were don e to assess wall motion 30 to 60 days later. In 238 segments with rest ing wall motion abnormalities, perfusion was more likely to present th an contractile reserve (97% versus 91%, P<.02). Revascularization resu lted in functional recovery in 77 of 95 hypokinetic segments (81%) but only 18 of 57 akinetic segments (32%, P<.0001). DSE and MCE were not significantly different in predicting functional recovery of hypokinet ic segments. In akinetic segments, DSE and MCE had similar sensitiviti es (89% versus 94%, respectively) and negative predictive values (93% and 97%, respectively) in predicting functional recovery. However, DSE had a higher specificity (92% versus 67%, P<.02) and positive predict ive value (85% versus 55%, P<.02) than MCE in predicting functional re covery. Conclusions Both contractile reserve by DSE and perfusion by M CE are predictive of functional recovery in hypokinetic segments after coronary revascularization in patients with chronic coronary artery d isease. In akinetic segments, myocardial perfusion by MCE may exist in segments that do not recover contractile function after revasculariza tion. Thus, contractile reserve during low-dose dobutamine infusion is a better predictor of functional recovery after revascularization in akinetic segments than perfusion.