ACUTE INTRAOPERATIVE ARTERIAL ELONGATION - HISTOLOGIC, MORPHOLOGIC, AND VASCULAR REACTIVITY STUDIES

This study focuses on the histomorphologic damage produced by an acute elongation process, as well as on quantifying the alterations in arte rial contractility following the application of this technique. Light microscopy and scanning electron microscopy studies were prepared from expanded and non-expanded pig superficial femoral arteries (SFA) harv ested immediately following expansion, and again at 24- and 72-hr inte rvals. Histologically, the expanded vessels showed minor, patchy, endo thelial slough, but no fragmentation of the internal or external elast ic lamina. At 24 hr, the endothelium showed reactive changes, but no e vidence of smooth-muscle necrosis of the tunica media was observed. At 72 hr, healing of the endothelium was evident by SEM. Similar specime ns, also from the SFA, were harvested and placed in organ chambers imm ediately following expansion and 24 hr later, to measure contractility when exposed to alpha-adrenergic agonists. The vessels were exposed t o the contractile agonists, phenylephrine and 5-hydroxytryptamine, whi ch evoked similar concentration-dependent increases in tension in both the expanded group and the controls. From these observations, the aut hors conclude that acute intraoperative elongation of arteries results in only minor endothelial damage, without affecting the inherent cont ractility of the vessel wall.