Evaluation of the Forearm Dominancy Artery for Invasive Vascular Procedure with 3D-CT Angiography

Use of multidetector computed tomography angiography of upper limb circulation in patients undergoing coronary artery bypass grafting surgery

OBJECTIVE

This study aimed to evaluate the bilateral forehand circulation using a 64-channel multidetector computed tomography (MDCT) as a noninvasive method to define criteria for an upper extremity arterial anatomy and pathology prior to the use of arterial conduits.

MATERIALS AND METHODS

Fifty-five patients with coronary artery disease who underwent total arterial coronary artery bypass grafting (CABG) were randomly selected for this prospective study. MDCT angiography was performed for 110 examinations of forearm and hand arterial anatomy. Prior to MDCT, Allen tests were performed in all patients with a normal result, except four. Thirteen patients had diabetes mellitus (DM), 8 had peripheral artery occlusive disease, and 19 had a history of smoking.

RESULTS

All arteries, including axillary, ulnar artery (UA) and radial artery (RA), were clearly visualized in all patients. Upper extremity anatomical and pathological results were examined in 16 patients (29.1%). Severely calcified RA and/or UA were found in 6 patients who had a moderate renal failure. Nearly total occlusion of the RA was detected in another two patients. Focal intimal RA calcification was recorded in 1 female and 3 male patients. Ten patients who had severe calcification or intimal sclerosis of the upper extremity arteries had DM. The remaining patients had normal forehand arterial circulation. A persistent median artery with the absence of radial and ulnar arteries and a high bifurcation of RA from the brachial artery was detected as an anatomic variation in seven patients (12.7%).

CONCLUSIONS

The major advantages of MDCT angiography are its non-invasiveness and the ability to detect calcific subadventitial plaques, which are difficult to diagnose using conventional angiography. MDCT may be used as a safe and non-invasive method to assess RA and UA prior to harvesting the upper limb artery. Preoperative imaging of forehand arteries is a means to avoid unnecessary forearm exploration or the use of an unsuitable arterial conduit in CABG operations, especially in patients with DM and moderate renal impairment.

Simultaneous computed tomographic angiography of the coronary and radial arteries

Our aim was to assess a method of simultaneous computed tomographic (CT) angiography of the coronary and radial arteries without increasing contrast medium usage. Radial access is a standard approach in coronary interventions. However, radial artery puncture is difficult due to the small size of the radial artery and potential unexpected anomaly. If we can obtain anatomical information on the radial artery beforehand, the success rate of radial artery puncture may increase. Simultaneous CT angiography of the coronary and radial arteries without increasing contrast medium usage was planned. Contrast medium was injected in the right elbow vein. Time to peak concentration of contrast medium in the aorta (TPA) and time to peak concentration of contrast medium in the radial artery (TPR) were obtained by the test scan in each patient based on the time-density curve. The main scan was performed using 265 mg iodine/kg of contrast medium. The start time was decided according to TPA and TPR, respectively. This study included 192 cases [age, mean ± standard deviation (SD),72.0 ± 9.9 years]. Mean TPA and TPR were 19.0 ± 2.3(SD) seconds and 34.0 ± 10.0 s, respectively. Clear images of radial arteries were obtained in 89.6% (right) and 84.9% (left). Radiation exposure during cardiac CT angiography (CCTA) and radial artery CT angiography (RCTA) was 269.9 ± 155.6 mGy cm and 31.1 ± 12.3 mGy cm as dose length product, respectively. RCTA immediately following CCTA was safely performed with minimal increase in radiation exposure and no additional contrast medium. These images can help in radial access as well as distal radial access in coronary interventions.