Intraoperative Low-dose Dobutamine Echocardiography Predicts the Post-pump Response of Dysfunctioning Myocardial Segments to Coronary Artery Bypass Grafting

Abstract

Background:Low dose dobutamine echocardiography has recently been introduced for use in identification of viable myocardium in patients with acute myocardial infarction and prediction of the response of dysfunctioning myocardial segments to coronary angioplasty. The aim of this study was to evaluate whether this test could be used to predict the early response of dysfunctioning myocardial segments to coronary artery bypass grafting(CABG. Methods:We studied in 23 patients with multi-vessel disease during CABG. Myocardial segments were monitored by intraoperative transesophageal echocardiography(TEE in the transgastric short-axis view at papillary muscle level. The left ventricle was divided into five segments and sixty eight myocardial segments in 23 patients were analyzed. Percentage of systolic wall thickening(PSWT was calculated in each segment for three times:at baseline(early after pericardiectomy; before bypass during dobutamine infusion(3-5ug/kg/min; and after seperation from cardiopulmonary bypass. Segments showing baseline PSWT ≥30% were considered normal and those <30% were dysfunctional. Segments showing an increase in PSWT ≥10% during dobutamine infusion were considered responders and those <10% nonresponders. Results:At baseline, 24(36% of 68 segments had PSWT ≥30%(normal and (4468% had * 본 논문의 일부는 가톨릭 중앙의료원의 보조로 이루어졌음.