Impact of Upper Arm Prolonged Occlusion on Radial Artery Diameter Before Coronary Angiography in Patients With Coronary Artery Disease.

Background: The transradial approach (TRA) for percutaneous coronary angiography and intervention has been increasingly gaining popularity in clinical practice. However, there are cases in which it is difficult to insert a sheath or catheter due to spasm, pulsation loss, and occlusion. It has been reported that flow-mediated dilatation (FMD) contributed to the reduction of complications due to the TRA and the improvement of the number of puncture attempts. We hypothesized that FMD might increase the radial artery diameter and plasma nitric oxide (NO).

Methods And Results: A prospective, single-blind, randomized, parallel-group, single-center study to investigate the effect of FMD on radial artery diameter. Fifty-four patients were enrolled and randomly assigned into the pressure group or non-pressure group. Radial artery diameter pre and post procedure and plasma NO after sheath canulation were analyzed in both groups. We measured the biological NO as its stable metabolic products, nitrite and nitrate, and express the results as total nitrogen oxides (NOx). The diameter of pre-procedural radial artery was similar between the 2 groups. However, in the pressure group, the increase of radial artery diameter between post- and pre-procedure was significantly greater than those in the non-pressure group (pressure group; 0.18 [0.07-0.29] mm vs. non-pressure group; -0.33 [-0.04 to -0.22] mm, p = 0.001). No significant differences were observed in terms of plasma NOx between the 2 groups.

Conclusions: It was possible to prove the increase in the radial artery diameter by performing FMD in the clinical practice, and to support the feasibility of FMD.