CORRELATION OF MYOCARDIAL HISTOLOGIC-CHANGES IN HIBERNATING MYOCARDIUM WITH DOBUTAMINE STRESS ECHOCARDIOGRAPHIC FINDINGS

Objective The objective of this study was to correlate histologic chan ges in hibernating myocardium with dobutamine stress echocardiography (DSE). Methods Patients (n = 8) with anterior regional wall motion abn ormalities in the seven echocardiographic segments representing the te rritory supplied by a significantly stenosed left anterior descending coronary artery had preoperative DSE performed (yielding 56 segments f or analysis). Two transmural biopsy specimens were taken from the ante rior wall of the left ventricle during coronary artery bypass grafting . Results Morphometric histologic analysis of biopsy specimens showed significantly less fibrosis in segments demonstrating inotropic reserv e (p < 0.05) and significantly less fibrosis in segments demonstrating improvement in wall motion on echocardiography 3 months after revascu larization (p < 0.05). DSE had a sensitivity of 100% and a specificity of 62% for detection of hibernating myocardial segments. Percent fibr osis was inversely correlated with percent nucleated cells (r = 0.66, p < 0.01) and directly correlated with cytoplasmic clearance (r = 0.76 , p < 0.01). Conclusion Inotropic response during DSE correlates with histologic evidence of hibernating myocardium.