A randomized trial of flow-mediated dilation to prevent radial artery spasm during transradial approach.

Background Although transradial approach has been increasingly preferred for percutaneous coronary interventions, radial artery spasm (RAS) is still one of the major disadvantage. Flow-mediated dilation (FMD) is a well-known method for assessing endothelial function through dilation. The aim of this study was to investigate the efficacy of prepuncture flow mediated dilation in preventing RAS during transradial approach. Methods The present study prospectively included 222 consecutive patients who underwent transradial coronary intervention. Patients were 1:1 randomized into two groups who underwent prepuncture FMD and who did not (FMD [+] and FMD [-], respectively). Results In FMD [+] group the incidence of RAS was lower (5.4% vs 16.2%, p=0.009). Multivariate logistic regression analysis demonstrated that female sex, more than two catheter usage and transradial approach without prepuncture FMD independently predicted RAS (odds ratio (OR): 4.66, 95% confidence interval [CI]: 1.8-12.06, p=0.001, OR: 5.73, 95%CI: 2.01-16.39, p=0.001, and OR: 5.01, 95% CI: 1.74-14.48, p=0.003; respectively). However, access site crossover number was very low in both groups and not different between groups. Conclusions Prepuncture FMD can significantly reduce RAS during transradial coronary interventions. Thus, prepuncture FMD can be used as a simple adjunctive method to prevent RAS.