Background: Radial artery harvest for coronary artery surgery leads to chronically elevated blood flow in the remaining ulnar artery. This study examined the ulnar artery for evidence of increased atherosclerosis compared with the contralateral ulnar artery where the radial artery had not been harvested.
Methods: Patients were enrolled at least seven years after unilateral radial artery harvest. Anatomical and flow data were acquired using a high-frequency ultrasound probe. Maximal forearm blood flow was measured after repeated hand grip with concurrent brachial artery occlusion to induce forearm ischemia.
Results: Eighty five patients, 71 males at age 71 +/- 9 years (43 to 88) were assessed at 8.4 +/- 1.0 years (7.2 to 11.1). There was no patient with ulnar artery atheroma on either side. Mild ulnar calcification was present in four patients bilaterally. The ulnar diameter after radial artery harvest was greater (2.8 +/- 0.5 vs 2.4 +/- 0.4 mm; p < 0.001), as was flow at rest (111 +/- 64 vs 59 +/- 41 mL/min; p < 0.001). However, the brachial artery flow was not different between the two sides at rest (169 +/- 90 vs 176 +/- 87 mL/min; p = 0.060) or after ischemic exercise (714 +/- 294 vs 753 +/- 315 mL/min; p = 0.485).
Conclusions: At an average of eight years after radial artery harvest, the remaining ulnar artery does not have evidence of increased atheroma and the maximal forearm blood flow is preserved.