Midterm angiographic patency and vasoreactive profile of proximal versus distal radial artery grafts

Background. No data are available on the different angiographic results and the in vivo vasoreactivity of radial artery (RA) grafts obtained from different parts of the conduit, although it is known that the distal segment of the artery has a more pronounced muscular component. This study was conceived to evaluate the angiographic patency and tendency to spasm of proximal versus distal RA grafts. Methods. In 29 patients, at the time of surgical myocardial revascularization, the radial artery was divided into two separate conduits, so that these patients received a total of 58 radial grafts (29 from the proximal and 29 from the distal portion of the artery). All cases were submitted to midterm angiography and vasoactive challenges to verify angiographic patency and vasoreactive profile. Results. Radial artery patency rate was 28 of 29 for both groups. Nine cases of string sign were reported, all in the distal series (p = 0.001). The perfect patency rate of distal grafts was markedly lower than that of proximal grafts (19 of 29 versus 27 of 29; p = 0.02). Vasoactive challenges testified to a higher vasospastic attitude of distal grafts. Conclusions. Radial artery grafts obtained from the distal portion of the artery have a higher vasospastic tendency, greater incidence of string sign, and lower midterm perfect patency rate than graft taken from the more proximal part of the artery. The proximal part of the RA should be preferred for use as a conduit for surgical myocardial revascularization. (c) 2005 by The Society of Thoracic Surgeons.