ACC/AHA/SCAI Coronary Revascularization Guideline: Key Perspectives

Question from a retired surgeon. As I recall, in the early days of CABG the greater saphenous vein was the conduit of choice. The size difference between a coronary artery and the greater saphenous was considered to be a cause of graft closure, so the lesser saphenous, usually harvested by the assistant surgeon, became the conduit of choice. (In a healthy leg, not affected by peripheral vascular disease, if the vein is harvested through short "bridged" incisions, the wounds heal quickly - unlike the images of gaping wounds once used to market expensive, nonreusable, endoscopic equipment). Later, the LIMA became the choice for grafting the LAD. Currently, many programs have returned to the use of the greater saphenous, usually harvested endoscopically by an RNFA or PA. Do we have data to compare the patency rate of surgeon harvested lesser saphenous conduits to the patency rate of endocsopically harvested greater saphenous grafts? If there is a difference, it might change the conversation regarding PCI vs CABG, and the use of the radial artery as a secondary graft. It was once taught that the LIMA graft to the LAD stayed open longer because most LAD disease was proximal, and that other branches of the coronary system were more likely to develop distal disease, thus negating the advantage of an arterial conduit to those branches. That is, a good lesser saphenous conduit would stay open until distal disease became the culprit. That thinking has obviously changed. Has it changed because we now have better data, or has it changed because we have returned to the use of the greater saphenous as a conduit - a conduit that is failing before distal disease becomes the culprit?