Endoscopic Vein-Graft Harvesting Fight Heats Up

A recent study published in the New England Journal of Medicine has raised a number of questions about the long term patency of endoscopically harvested saphenous veins that are collected and used for coronary artery bypass grafts. The study from Duke, based on a secondary analysis of the PREVENT IV data, concluded that endoscopic vein-graft harvesting is “independently associated with vein-graft failure and adverse clinical outcomes.”
Maquet, the maker of the popular Vasoview EVH system, has now fired back saying the study is “subject to a number of important limitations,” because it is based on a secondary data analysis. This is of course true, and we do need further randomized clinical tests to evaluate the safety and effectiveness of the endoscopic harvesting technique. But what we also need to realize is that one of the possible reasons that these grafts might be failing in the long term is because the vessels might be experiencing high degree of thermal trauma. Our own editors, in the course of their clinical practice, have seen many endoscopically harvested veins that showed burn marks. Albeit usually tiny in size, these burns probably come from the electrical cutting endoscopic scissors, that are routinely used to remove small side branches from the saphenous vein.
We don’t know whether burns play any negative long-term role in the lives of the grafts, or whether they are clinically insignificant. But we have a recommendation for Maquete and other manufacturers. To eliminate any questions about the technique, they should develop small endoscopic clip devices, that can be used to occlude side branches, as well as a regular endoscopic scissors that surgeon can use to cut vessels, once they’ve been occluded. Sure, this will make the technique more laborious, but it will surely eliminate the thermal factor altogether from the equation.