Effect of topical vasodilators on gastroepiploic artery graft

Abstract

Background. Mobilization of the gastroepiploic artery (GEA) often results in a vasospasm with reduction of early graft flow. In order to prevent or suppress this highly reactive artery’s spasm, we have compared the effect of 4 vasodilators, used in external application to prepare the GEA graft, prior to myocardial revascularization. Methods. We performed a double-blind clinical study to compare the effects of external application of vasodilators on gastroepiploic artery grafts. Fifty patients, whose gastroepiploic artery was used for coronary artery bypass grafting, were randomized into 5 groups of 10 patients. Gastroepiploic artery free flow and hemodynamic measurements were evaluated immediately after harvesting, before any pharmacological manipulation, and 10 minutes after the topical application of vasodilators, respectively: papaverine, linsidomine, nicardipine, glyceryl trinitrate, and normal saline solution. Results. A significant increase in free flow occurred in all groups except for 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 flow before and after local application occurred with glyceryl trinitrate and papaverine: from 25.5 ± 2 mL/min to 50 ± 6.1 mL/min ( p ≤ 0.01) and from 36.8 ± 3.2 mL/min to 62 ± 7.8 mL/min ( p < 0.01) respectively. 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 comparing percentage of flow increase, glyceryl trinitrate appeared to be significantly more efficient than nicardipine and linsidomine ( p < 0.01 versus both groups). Although papaverine was more efficient than nicardipine and linsidomine, it did not reach statistical significance. Conclusions. During intraoperative preparation of the GEA graft, glyceryl trinitrate and papaverine to a lesser extent, used as topical vasodilators, appear to be more efficient in external application to increase the free flow of the GEA.