Gurné O, Chenu P, Buche M, Jamart J, Louagie Y, Eucher P, Marchandise B, Schroeder E
Department of Cardiology, University of Louvain, Mont-Godinne Hospital, Yvoir, Belgium.
J Am Coll Cardiol. 1996 Feb;27(2):415-20. doi: 10.1016/0735-1097(95)00453-x.
The free epigastric artery bypass graft is proposed as an alternative conduit to the saphenous vein graft, known for its high rate of attrition. The aim of our study was to assess its endothelial function in vivo.
The endothelium of arterial bypass grafts plays a role in both the performance and the patency of such grafts.
We studied 73 epigastric grafts early (mean +/- SD 10 +/- 3 days) and 36 late (12 +/- 5 months) after coronary bypass surgery with quantitative angiography at rest, after 2 min of atrial pacing (130 beats/min) and after injection of isosorbide dinitrate (1 to 2 mg) into the graft.
At rest, mean epigastric graft diameter was lower in the late than in the early postoperative period (2.26 +/- 0.39 vs. 2.61 +/- 0.49 mm, p < 0.001). Early after operation, epigastric grafts with a small or an intermediate runoff, but not those with a large runoff, were capable of vasodilation with nitrates (+0.09 +/- 0.10 mm). Late after operation, vasodilation after administration of isosorbide dinitrate was similar in epigastric grafts with a large runoff and in those with a small or intermediate runoff (+ 0.23 +/- 0.09 vs. +0.23 +/- 0.18 mm). Significant vasodilation during pacing was observed late (+4 +/- 9%, p < 0.01) but not early postoperatively, except in a subset of patients with grafts capable of vasodilation after nitrates. A correlation between the response to nitrates and the response during pacing was observed early (r = 0.579, p < 0.001) and late postoperatively (r = 0.530, p = 0.02).
Flow-mediated vasodilation during pacing was observed in most epigastric grafts late, but not early, after operation. This endothelium-dependent dilation was correlated with the importance of the vasodilation observed with nitrates (endothelium-independent), which was related to the importance of the runoff only in the early postoperative period. The ability of epigastric grafts late postoperatively to dynamically adapt their dimensions to an acute increase in demand could contribute to the good functional results of this new alternative arterial graft.
游离腹壁上动脉旁路移植血管被提议作为大隐静脉移植血管的替代管道，后者因较高的损耗率而闻名。我们研究的目的是评估其体内内皮功能。
动脉旁路移植血管的内皮在这类移植血管的性能和通畅性方面均发挥作用。
我们在冠状动脉旁路手术后早期（平均±标准差10±3天）研究了73例腹壁上移植血管，在晚期（12±5个月）研究了36例，通过静息状态下、心房起搏2分钟（130次/分钟）后以及向移植血管内注射硝酸异山梨酯（1至2毫克）后的定量血管造影进行研究。
静息状态下，晚期腹壁上移植血管的平均直径低于术后早期（2.26±0.39对2.61±0.49毫米，p<0.001）。术后早期，血流为少量或中等量的腹壁上移植血管能够对硝酸盐产生血管舒张反应（增加0.09±0.10毫米），但血流为大量的移植血管则不能。术后晚期，给予硝酸异山梨酯后，血流为大量的腹壁上移植血管与血流为少量或中等量的移植血管的血管舒张反应相似（增加0.23±0.09对增加0.23±0.18毫米）。起搏期间的显著血管舒张在术后晚期观察到（增加4±9%，p<0.01），但术后早期未观察到，除了一部分移植血管对硝酸盐有血管舒张反应的患者。术后早期和晚期均观察到对硝酸盐的反应与起搏期间的反应之间存在相关性（早期r = 0.579，p<0.001；晚期r = 0.530，p = 0.02）。
术后晚期大多数腹壁上移植血管观察到起搏期间的血流介导的血管舒张，但术后早期未观察到。这种内皮依赖性舒张与硝酸盐诱导的血管舒张（非内皮依赖性）的程度相关，而后者仅在术后早期与血流情况有关。术后晚期腹壁上移植血管动态调整其尺寸以适应需求急性增加的能力可能有助于这种新型替代动脉移植血管取得良好的功能结果。
