Effect of topical vasodilators on gastroepiploic artery graft

Background. Mobilization of the gastroepiploic artery (GEA) often results i n a vasospasm with reduction of early graft flow. In order to prevent or su ppress this highly reactive artery's spasm, we have compared the effect of 4 vasodilators, used in external application to prepare the GEA graft, prio r to myocardial revascularization. Methods. We performed a double-blind clinical study to compare the effects of external application of vasodilators on gastroepiploic artery grafts. Fi fty patients, whose gastroepiploic artery was used for coronary artery bypa ss grafting, were randomized into 5 groups of 10 patients. Gastroepiploic a rtery free flow and hemodynamic measurements were evaluated immediately aft er harvesting, before any pharmacological manipulation, and 10 minutes afte r the topical application of vasodilators, respectively: papaverine, linsid omine, nicardipine, glyceryl trinitrate, and normal saline solution. Results. A significant increase in free now occurred in all groups except f or the normal saline solution group with measurements from 26.1 +/- 3.6 mL/ min to 26.4 +/-. 6.5 mL/min; p = 0.9. The most important increase in now be fore and after local application occurred with glyceryl trinitrate and papa verine: from 25.5 +/- 2 mL/min to 50 +/- 6.1 mL/min (p less than or equal t o 0.01) and from 36.8 +/- 3.2 mL/min to 62 +/- 7.8 mL/min (p < 0.01) respec tively. Nicardipine and linsidomine produced a less significant increase in flow: from 33.1 +/- 3.6 mL/min to 47.7 +/- 8.9 mL/min (p < 0.05) and from 28 +/- 3.8 mL/min to 39.8 +/- 7.5 mL/min (p < 0.05) respectively. When comp aring percentage of flow increase, glyceryl trinitrate appeared to be signi ficantly more efficient than nicardipine and linsidomine (p < 0.01 versus b oth groups). Although papaverine was more efficient than nicardipine and li nsidomine, it did not reach statistical significance. Conclusions. During intraoperative preparation of the GEA graft, glyceryl t rinitrate and papaverine to a lesser extent, used as topical vasodilators, appear to be more efficient in external application to increase the free no w of the GEA. (Ann Thorac Surg 1999;67:1295-8) (C) 1999 by The Society of T horacic Surgeons.