Background The radial artery has become a widely used approach for coronary angiography and intervention in patients, and the ulnar artery is another approach for elective procedure in patients.

Objective The objective of this study was to investigate the diameter, peak flow rate of blood flow and anatomy abnormalities of radial arteries and ulnar arteries of left and right forearm and to identify the influencing factors of the diameter of radial arteries and ulnar arteries in Chinese adult patients.

Methods 1112 consecutive adult patients who were to accept the selective transradial or transulnar procedures including coronary angiography and percutaneous coronary intervention were enrolled. To examine the radial arteries and ulnar arteries of left and right fore arm with colour Doppler ultrasound, to measure the diameter, peak flow rate of blood flow and anatomy abnormalities of radial arteries and ulnar arteries.

Results The diameters of right radial artery and ulnar artery were 2.316±0.507 mm vs 2.247±0.518 mm respectively; and the diameters of left radial artery and ulnar artery were 2.324±0.486 mm vs 2.238±0.520 mm respectively, there were no statistical difference (p>0.05). The diameters of radial arteries and ulnar arteries of male patients were larger than those of female patients (p<0.05), but the peak flow rates of blood flow of radial artery and ulnar artery of both sides in male and female patients were similar, and there was statistical difference (p>0.05). The total incidence of anatomy abnormalities of forearm arteries was 26.5%. There were 91.9%, 77.3%, 51.9% and 23.6% of total patients whose right radial artery diameter were larger and equal to the outer diameter of 5 Fr, 6 Fr, 7 Fr and 8 Fr sheathe, respectively. Gender and arm circumference were the influencing factors of diameters of radial arteries and ulnar arteries of forearm.

Conclusions The diameters and the peak flow rates of blood flow of radial arteries and ulnar arteries of both sides were similar. The diameters of radial arteries and ulnar arteries in male patients were larger than those in female patients. The incidence of anatomy abnormalities of radial arteries were more than those of ulnar arteries. The gender and arm circumference were the influencing factors of diameters of radial arteries and ulnar arteries of forearm.