Expansion Pressure Of The Rabbit Vein Graft Restenosis

OBJECTIVES: Saphenous vein (SV) is one of the most common used vascular materials for CABG, but restenosis of these vein grafts remains a clinical problem. Early vein graft failures are attributed to thrombosis. Late failures are the results of intimal hypertension. Overdistension during surgical preparation was considered one of the causes of thrombosis and intimal hypertension. Using a rabbit model of the external jugular veins grafted end to end into the common carotid arteries, this study tested the effects of different distension pressures on the integrity of the endothelium of rabbit external jugular veins, endothelium dependent relaxation to calcium ionophore A23187, and vein grafts restenosis. Expression of c-myc and c-fos mRNA of vein grafts also tested.METHODS: Rabbit external jugular veins were distended for 1 minute with heparinized normal saline solution containing papaverine under pressure of 50 mmHg (n=6), 100 mmHg (n=6) and 200 mmHg(n=6) respectively. Then the veins were cut into 3 segments. One was for EC integrity...