Real Time Intraprocedural Ultrasound Measurements of the Radial and Ulnar Arteries in 565 Consecutive Patients Undergoing Cardiac Catheterization and/or Percutaneous Coronary Intervention via the Wrist: Understanding Anatomy and Anomalies May Improve Access Success

OBJECTIVES: Ultrasound evaluation of both the radial artery (RA) and ulnar artery (UA) in patients undergoing cardiac catheterization/percutaneous coronary intervention. BACKGROUND: Arterial access from the wrist is almost exclusively obtained from the RA. Crossover to secondary femoral arterial access was observed in up to 7.6% in randomized multicenter trials utilizing palpation guided RA access. METHODS: Intraprocedural ultrasound evaluation of the RA and UA was performed in a consecutive series of patients. A difference of ≥20% in diameter was defined as significant. In the case of a dual artery, measurements of the dual arteries and the proximal confluens were obtained. RESULTS: A total of 566 RA/UA measurements were analysed (patients: n = 565, female: n = 201 [35.5%], mean age: 66.5 years). Overall, the RA measured 3.03 ± 0.57 mm and the UA 2.70 ± 0.57 mm (P < 0.01). The RA was larger in 210 (37.1%) and the UA in 37 (6.5%) measurements. A dual RA was present in 25 (4.4%) measurements. The mean diameters of the smaller and larger of the dual RAs were 1.82 ± 0.37 and 2.59 ± 0.36 mm (P < 0.01). The corresponding proximal confluens measured 3.10 ± 0.40 mm. No dual UA was observed. CONCLUSION: In 10.9 % of patients, a larger UA or a dual RA with a more accessible confluens was observed. This information can only be obtained using ultrasound and may improve arterial access from the wrist if the larger UA or RA confluens is accessed instead of blind palpation guided RA access.