Feasibility and Safety of the Routine Distal Transradial Approach in the Anatomical Snuffbox for Coronary Procedures: The ANTARES Randomized Trial

The distal transradial approach (dTRA) through the anatomical snuffbox is hypothesized to offer greater benefits than the conventional transradial access (cTRA) for patients undergoing coronary procedures. Our goal was to assess the safety and efficacy of dTRA. Out of 465 consecutive Caucasian patients, 400 were randomized (1:1) to dTRA or cTRA in a prospective single-center trial. Clinical and ultrasound follow-ups were obtained at 24 h and 60 days post-procedure. The primary combined endpoint consisted of access crossover, access-related complications, and major adverse cardiovascular events (MACE). Secondary endpoints included clinical success endpoints (puncture success, crossover, and access time), access-site complications endpoints, and MACE at 60 days. The primary endpoint was significantly higher in the dTRA [odds ratio (OR): 2.31, 95% confidence interval (CI): 1.38-3.86, p = 0.001]. Clinical success endpoints, namely crossover (10% vs. 3.5%, p < 0.05) and access-time [median: 140s (85-322) vs. 80s (58-127), p < 0.001], did not favor the dTRA, despite a similar success rate in radial artery puncture between the dTRA and cTRA (99.5% vs. 99%). Radial artery spasm (19% vs. 4.5%, p < 0.0001), physical discomfort during access, and transient thumb numbness after the procedure occurred more frequently with the dTRA. However, early (2.5% vs. 4.5%, p = 0.41) and mid-term (2.5% vs. 3%, p = 0.98) forearm radial artery occlusion rates were comparable between the dTRA and cTRA. Randomization to the dTRA, lower forearm radial pulse volume, higher body mass index, and lower body surface area independently predicted the primary endpoint in multivariate analysis. In the interaction effect analysis, only diabetes increased the incidence of the primary endpoint with the dTRA (OR: 18.67, 95% CI: 3.96-88.07). The dTRA was a less favorable strategy than cTRA during routine coronary procedures due to a higher incidence of arterial spasm and the necessity for access crossover. The majority of local complications following the dTRA were clinically minor complications. Individuals with diabetes were particularly susceptible to complications associated with the dTRA.