Integrity Of Endothelial Lining Research Articles

Shunt or Snare: Coronary Endothelial Damage due to Hemostatic Devices for Beating Heart Coronary Surgery

Occlusion of coronary arteries during off-pump coronary bypass operations bears the potential for endothelial injury. The aim of this study was to elucidate the effects of hemostatic devices on the beating heart in human coronaries by means of scanning electron microscopy. The coronary arteries of 9 patients with dilated cardiomyopathy and 13 with ischemic heart disease undergoing heart transplantation were handled with intracoronary shunts as well as external snaring techniques on a beating heart, after cannulation but before starting cardiopulmonary bypass. Adjacent noninstrumented coronary artery segments served as controls. Integrity of endothelial lining was observed with scanning electron microscopy. Nearly all coronary artery segments manipulated with a shunt exhibited a severe injury with extensive endothelial denudation. Endothelial injury was significantly higher after manipulation with intracoronary shunts compared with external occlusion devices (p < 0.001) or control specimens (p < 0.001). Plaque rupture was apparent in 3 samples. Manipulation of human coronary arteries during off-pump operations leads to endothelial denudation and plaque rupture. From this investigation we conclude that insertion of intracoronary shunts during beating heart operations leads to severe endothelial denudation in human coronary arteries. We therefore recommend using shunts selectively in cases where critical ischemia or technical difficulties due to anatomic conditions are expected during anastomosis. The clinical significance of these structural damages has to be further investigated with clinical trials.

Coronary endothelial injury after local occlusion on the human beating heart

Background. Occlusion of coronary arteries during beating heart surgery bears the potential for mechanical trauma to the arterial wall with consequent endothelial injury. The aim of this study was to elucidate the effects of local occlusion on the beating heart in human coronary arteries. Methods. Coronary arteries of patients with dilated cardiomyopathy (n = 7) or ischemic heart disease (n = 10) undergoing heart transplantation were locally occluded after starting cardiopulmonary bypass. Immediately after excision of the diseased heart, the vessels were fixed. Unoccluded segments served as controls. Integrity of endothelial lining was observed with scanning electron microscopy. Results. Scanning electron microscopy revealed significantly more severe endothelial injury in the area of occlusion than in the adjacent, not manipulated control segments. In the region of local occlusion, plaque rupture was noted in three of 34 atherosclerotic vessel specimens, injury to side branches was evident in two of 44, and local microthrombus formation was evident in six of 44 samples. Conclusions. Local occlusion of human coronary arteries during beating heart coronary surgery may cause focal endothelial denudation, local microthrombosis, atherosclerotic plaque rupture, and injury to target vessel side branches.