MORE EVIDENCE ON FAILURE OF RADIAL ARTERY GRAFTS FOR CABG

CABG is a very matured operation now, in patients with CAD who needed re-vascularisation. One of the biggest problem with CABG is graft attrition, or failure / re-blockage of graft months or years after the surgery. There are alot of data showing that the saphenous vein graft is a poor conduit ( except perhaps in the hands of the late Dr Victor Chiang ). The left internal mammary graft is excellent, and should be used whenever possible. The radial artery, free pedicle graft, is an enigma, as data seem weak and conflicting. There are some cardiac surgeons who prefer the radial artery graft, thinking that since it is an arterial conduit, it should last better then the saphenous vein graft, maybe just a little inferior to the left internal mammary graft. I remember discussing with some cardiac surgeons, that the radial artery graft is a poor conduit because it is a free arterial pedicle graft. It cannot behave in anyway the same as the left internal mammary graft. Alas, they keep on doing it.
Well, the just concluded American College of Cardiology annual scientific meeting in Atlanta had a paper on this.
The study is called the CSP 474 study, led by Dr Steve Goldman, comparing the use of the radial artery graft with saphenous vein grafts in the treatment of CAD across 11 VA hospitals, involving 733 patients. 366 patients in the radial artery graft arm, and 367 patients in the saphenous vein arm. At one year followup, angiography was done to see graft patency. Angiographic followup was 73% ( not bad for a VA hospital ). Well it showed basically that the radial artery graft was no better then the venous graft ( as expected ). In each arm, at 1 year, graft attrition was 11%. The worse candidates was in the venous graft arm, who had the veins harvested using a videoscope, for off-pump bypass. ( Cardiac surgeons doing off-pump try to save time and minimising trauma, by using a videoscope to harvest veins, or even radial artery, as conduit for bypass. The technique is so rough and traumatic ( I saw a videoscopic presentation of it ) that it is not surprising that at the end of the harvesting, the veins is all but smah up and the endothelial integrity is all gone, that they very quickly close off.
Anyway, looks like the latest information would suggest that the radial artery is a poor conduit. Perhaps the cardiac surgeon would leave them alone, as they are very useful for the interventionist to do their transradial interventions.