Radial artery characteristics before and after intra-arterial administration of nitroglycerin and verapamil: an optical coherence tomography study.

BACKGROUND

Radial artery dimensions before and after intra-arterial vasodilator administration remain incompletely characterized along the vessel. This study used optical coherence tomography (OCT) to assess paired changes in mean lumen diameter.

METHODS

Twelve patients underwent baseline OCT 5 min after limited sheath insertion and post-administration OCT after intra-arterial nitroglycerin and verapamil, before coronary angiography. The full OCT-imaged radial artery span was divided into equal proximal, middle, and distal thirds before selecting anatomically matched analyzable portions. Analysis included 1,482 matched cross-sectional pairs (2,964 frames), with a cumulative matched analyzable length of 1,404.4 mm. Measurements at matched 1-mm intervals were aggregated within patients. Mean lumen diameter was the representative lumen metric; area and volume were supportive measurements.

RESULTS

Mean lumen diameter increased from 3.06 ± 0.49 to 3.35 ± 0.56 mm (mean paired change, 0.29 mm; 95% CI, 0.20-0.39; P < 0.001). The mean patient-level relative increase was 9.6%. Mean increases were observed in all three thirds in exploratory analyses.

CONCLUSIONS

Mean radial artery lumen diameter was greater after intra-arterial nitroglycerin and verapamil than at baseline.

CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/hvshowproject.html?id=270,922&v=1.1, Chinese Clinical Trial Registry (ChiCTR) ChiCTR2500097574.