Comparison of low-dose dobutamine ventriculography with low-dose dobutamine echocardiography for predicting regional improvement in left ventricular function after coronary artery bypass grafting

The demonstration of a contractile reserve during low-dose dobutamine echoc ardiography (LDDE) identifies viable myocardium and predicts recovery of le ft ventricular (LV) function after myocardial revascularization in patients with chronic coronary artery disease. However, a technically difficult tra nsthoracic visualization may limit the use of LDDE, thus requiring an alter native diagnostic procedure. The present study compares LDDE with low-dose dobutamine ventriculography (LDDV) in predicting an improvement in regional LV function after surgical revascularization, We studied 18 patients with coronary artery disease and LV dysfunction who were to undergo coronary art ery bypass grafting. Preoperatively, all patients were evaluated for the pr esence of viable myocardium using LDDE and LDDV. Follow-up echocardiography at rest and left ventriculography were performed 4 months after successful revascularization to assess recovery of LV function. The sensitivity and s pecificity of LDDE to identify dysfunctional segments capable of recovering function were 63% and 71%, respectively, with a diagnostic accuracy of 68% . The sensitivity, specificity, and diagnostic accuracy of LDDE improved to 81%, 72%, and 76% when patients with optimal transthoracic evaluation were selected, whereas they were 30%, 77%, and 57%, respectively, in those who underwent suboptimal evaluation. The sensitivity, specificity, and diagnost ic accuracy of LDDV were 66%, 75%, and 71%, respectively, with no differenc e in subgroups of patients. This study demonstrates that LDDV can be consid ered a useful technique for identifying the presence of myocardial viabilit y and may provide an advantage over LDDE in patients with suboptimal echoca rdiographic visualization. (C) 2000 by Excerpta Medica, Inc.