Exposure

Abstract

Exposure of the target coronary artery is the first step in successful off-pump coronary artery bypass grafting (OPCAB). Deep pericardial suture (“Lima suture”) and other modified techniques have contributed to the widespread use of OPCAB. In the basic deep pericardial stitch technique, the posterior pericardium is lifted up with three sutures and the heart is displaced. OPCAB has become more widely used since suction-assisted heart positioning devices were developed. Apical suction devices are only applied at the apex, and the heart is lifted and rotated to expose the target coronary artery. Our group developed a multi-suction heart positioner, Tentacles, which can facilitate this exposure. Patient positioning is also effective in any heart displacement technique. The operating table should be tilted in the Trendelenburg position and rotated sideways to the right for exposure of the left circumflex territory and the inferior territory. Heart displacement can cause hemodynamic instability in any heart positioning technique. Positioning for the left circumflex territory results in the greatest impairment to circulation compared to other territories. The main cause of hypotension is right ventricular kinking/obstruction, regional wall motion abnormality caused by compression and regional ischemia, and mitral regurgitation caused by mitral annular distortion. Fluid redistribution, patient positioning, catecholamine infusion, coronary perfusion during distal anastomosis, and pacing are effective in improving circulation.