Similarity between internal thoracic artery and gastroepiploic artery graft: pharmacological point of view

The pharmacological responses of internal thoracic artery (ITA), gastroepiploic artery (GEA) and saphenous vein (SV) obtained from patients receiving coronary artery bypass grafting (CABG) were assessed by isometric contraction records. The concentration-response curves for ergonovine and serotonin showed the leftward shift in SV compared with ITA and GEA. The 50% effective dose values of SV for ergonovine and serotonin were significantly less than those of ITA and GEA. The concentration-response curves for phenylephrine were similar among three kinds of grafts. There were no significant differences in the 50% effective dose values for phenylephrine among them. The effect of 0.4% papaverine chloride on the free graft flow was assessed in 15 patients receiving CABG with mean body surface area of 1.62 +/- 0.12 M2. The free flow of ITA graft was 71 +/- 32 ml/min before intraluminal papaverine injection, and that increased to 112 +/- 41 ml/min after injection. The free flow of GEA graft was 82 +/- 39 ml/min before injection, and that also increased to 128 +/- 40 ml/min after injection. The patency rates at the mean 2.2 months after grafting were 98% in ITA, 93% in GEA, and 88% in SV. In conclusion, both GEA graft and ITA graft can be expected as an excellent conduit in myocardial revascularization.