Radial anomalies in North Indian patients undergoing TRAns-radial catheterization: A prospective observational study (RAIN-TRAC study)

Background: Radial artery anomalies are relatively common and one of the major causes of transradial procedure failure. Aim: The study was aimed to assess the incidence of radial axis anomalies in patients undergoing transradial cardiac catheterization and their impacts on procedural failure. Materials and Methods: This was a prospective, single-center study, 1870 consecutive patients underwent transradial coronary catheterization. Radial artery anatomy was determined by injecting diluted contrast agent through radial sheath. Results: About 11.4% patients (213/1870) were noted to have abnormal radial artery anatomy which was associated with significantly higher procedural failure rate (odds ratio [OR] [95% confidence interval [CI] = 240.72 [57.98–999.43]) and radial artery spasm (OR [95%CI] = 7.12 [4.06–12.49]) than patients with normal radial artery anatomy. Among all the radial artery anomalies, high bifurcation was the most common anomaly, found in 128 (60%) patients. The high bifurcation was found most commonly at the mid-humerus level (53.12%). Extremely tortuous radial artery was found in 43 (20%) patients. Radial artery loop was found in 22 (10%) patients and was associated with the highest failure rate (54.5%). Other unclassified anomalies were found in 20 patients (10%). In bivariate analysis, the incidence of each of the radial artery anomalies was found to have significant correlation with older age, short stature, female sex, and hypertension. Conclusion: Radial artery anomalies are not uncommon and are related to significant procedural failure. Retrograde radial arteriography helps to identify patients with unfavorable radial artery anatomy, which can be performed with a minimum amount of contrast and should be considered part of a routine transradial procedure.