Assessment of the radial artery and hand circulation by computed tomography angiography: a pilot study

The radial artery (RA) is increasingly being used as a coronary bypass graft. Results of a previous study using Doppler ultrasound and histopathologic examinations indicated that the RA has a higher incidence of preexisting intimal hyperplasia, medial calcification, and atherosclerosis than the internal thoracic artery. The aims of this study were to evaluate the use of computed tomographic angiography (CTA) to display hand collateral circulation, to define the criteria for an abnormal CTA test result, and to demonstrate usefulness of CTA as an alternative to conventional angiography for evaluation of the radial artery.

Sixteen patients scheduled for coronary artery bypass grafting entered this study. We performed 32 examinations of forearm and hand arterial anatomy in these patients. CTA was performed in patients with a normal Allen test result, except 1 patient who had a persistent median artery. Soft tissue density forehand roentgenography was performed in all patients before the CTA evaluation. There was no selection of patients in relation to patient characteristics. As a risk factor for radial artery calcification, 6 of the patients had diabetes mellitus, 6 had aortofemoral occlusive disease, and 4 had a history of smoking.

Bilateral forearm arteries were visualized in all patients. Severe RA calcification was found in 1 patient, and distal occlusion was found in another patient. Focal RA calcification was noted in 2 patients. In the remaining patients no radial artery calcification or occlusion was noted. Anatomic variation of the upper limb arteries was shown in 2 patients; these variations were persistent median artery with absence of the radial and ulnar arteries and high bifurcation of the radial artery from the brachial artery.

CTA is useful and safe for detection of radial artery calcific disease and assessment of the forehand circulation and its anatomic variations. Preoperative imaging of the RA is a means to avoid unnecessary forearm exploration or inadvertent use of a diseased conduit in coronary artery bypass candidates with multiple risk factors such as diabetes mellitus.