DOBUTAMINE STRESS ECHOCARDIOGRAPHY IDENTIFIES HIBERNATING MYOCARDIUM AND PREDICTS RECOVERY OF LEFT-VENTRICULAR FUNCTION AFTER CORONARY REVASCULARIZATION

Background. The identification of hibernating myocardium is important in selecting patients who will benefit from coronary revascularization. This study was performed to determine whether dobutamine stress echocardiography (DSE) could identify hibernating myocardium and predict improvement in regional systolic wall thickening after revascularization. Methods and Results. DSE was performed in 49 consecutive patients with multivessel coronary disease and depressed left ventricular function. Contractile reserve during DSE was defined by the presence of two criteria: (1) improved systolic wall thickening in at least two adjacent abnormal segments and (2) greater-than-or-equal-to 20% improvement in regional wall thickening score. Postoperative echocardiograms were evaluated for improved regional wall thickening in 25 patients at least 4 weeks after successful coronary revascularization. All studies were read in blinded fashion. Contractile reserve during DSE was present in 24 (49%) of 49 patients. The presence or absence of contractile reserve on preoperative DSE predicted recovery of ventricular function in the 25 patients who underwent successful revascularization. Thus, 9 of 11 patients with contractile reserve had improved systolic wall thickening after revascularization (hibernating myocardium), whereas 12 of 14 patients without contractile reserve did not improve (P=.003). Conclusions. Dobutamine stress echocardiography provides a simple, cost-effective, and widely available method of identifying hibernating myocardium and predicting improvement in regional left ventricular wall thickening after coronary revascularization. This technique may be clinically valuable in the selection of patients for coronary revascularization.