Efficacy and safety of the distal transradial approach in coronary angiography and percutaneous coronary intervention: a Japanese multicenter experience

The novel distal transradial approach (dTRA) is expected to further build upon the advantages of transradial access. However, the incidence of radial artery occlusion (RAO) and hemorrhagic events with the dTRA has not been fully elucidated. The objective of this study was to investigate the effects of using the dTRA on RAO and postprocedural hemorrhage. From April 2018 to July 2018, 228 consecutive patients who underwent coronary angiography or intervention through the dTRA at two hospitals were analyzed. The RAO rate, change in the forearm and distal radial artery diameter and cross-section area after the dTRA (at 1 day and 1 month) on vascular ultrasonography, and incidence of hemorrhagic complications were investigated. Forearm and distal RAO occurred in 1 (0.4%) and 8 (3.1%) patients at 1 month, respectively. No forearm hematomas occurred. Ultrasonographic findings indicated that the radial artery diameter and cross-section area were significantly larger after the dTRA (2.9 ± 0.5 mm vs. 2.7 ± 0.5 mm, p < 0.001 and 6.5 ± 2.4 mm² vs. 5.6 ± 2.0 mm², p < 0.001, respectively). The distal radial artery diameter and cross-section area in the anatomical snuffbox were also significantly larger after the dTRA (2.5 ± 0.5 mm vs. 2.3 ± 0.4 mm, p < 0.001 and 4.7 ± 2.0 mm² vs. 4.2 ± 1.6 mm², p < 0.001, respectively). The DTRA was associated with a low incidence of RAO at both the puncture site and the forearm, postprocedural dilatation of the radial artery, and no bleeding complications extending to the forearm.