Coronary artery bypass grafting on the beating heart evaluated with integrated backscatter

Background. In beating heart coronary artery bypass grafting (CABG) the eff ect of ischemic insult during coronary occlusion could not be evaluated imm ediately. Using transesophageal echocardiography, myocardial performance ca n be evaluated with analysis of integrated backscatter. Methods. In 15 beating heart CABGs, cyclic variation (CV) of integrated bac kscatter of the anterior wall before, during, and after the left internal t horacic artery to left anterior descending (LAD) branch anastomosis was mea sured with transesophageal echocardiography. The patients were divided into two groups according to collateral vessels status (good collateral group n = 6, poor collateral group n = 9). Results. In all patients, CV increased significantly after revascularizatio n (8.56 +/- 2.50 to 11.47 +/- 3.32 dB, p < 0.0001). During LAD occlusion, s ignificant decrease in CV was found in patients who had poor collateral art eries. At 15 minutes of LAD occlusion, CV decreased from the preocclusion v alue of 7.51 +/- 2.21 to 3.23 +/- 4.03 dB (p < 0.01). Conclusions. Measurement of CV can detect the ischemic insult during corona ry occlusion and the effect of revascularization in beating heart CABG. (An n Thorac Surg 2000;70:1049-53) (C) 2000 by The Society of Thoracic Surgeons .