Intravascular ultrasound analysis of the radial artery for coronary artery bypass grafting.

Background: The radial artery has become a popular conduit for coronary artery bypass surgery. However, limited information has been provided regarding the atherosclerotic nature of this artery, which may affect both the immediate intraoperative difficulties and long-term graft patency.

Methods: We examined intravascular ultrasound (IVUS) images of the radial artery in patients with coronary artery diseases. Cross sections of the radial artery were assessed using the following factors: lumen diameter, lumen area, vessel diameter, vessel area, plaque area, percent plaque area, and extent of calcium deposition.

Results: The IVUS images were obtained from radial arteries of 58 patients (47 men, average 67 +/- 9 years) during transradial procedures; ie, transradial coronary angiography and/or transradial coronary intervention. Mean luminal diameter was 3.28 +/- 0.69 mm and 3.00 +/- 0.70 mm at the proximal and distal segments, respectively, and 2.58 +/- 0.73 mm at the minimal lumen cross section. A percent plaque area greater than 50% was seen in five radial arteries (8.6%) whose average plaque length was 26.4 +/- 30.8 mm. Of these, one showed a plaque length greater than 50 mm, and another showed vessel caliber less than 2.0 mm. Five of 58 radial arteries (8.6%) showed calcium deposition, two of which showed diffuse calcification (> 50 mm). Thus, among 58 radial arteries, four (6.9%: one with diffuse arteriosclerosis, one small radial artery, two with diffuse calcification) were considered unsuitable for bypass conduit.

Conclusions: Preoperative evaluation of the radial artery is recommended in order to prevent unnecessary exploration of the forearm and to improve graft patency.