Feasibility and Challenges of Transradial Approach in Neuroendovascular Therapy: A Retrospective Observational Study

Abstract

Objective: Transradial approach (TRA) is increasingly used as a viable alternative to the traditional transfemoral approach (TFA) in neuroendovascular therapy (NET) owing to its potential anatomical benefits and lower puncture-site complication rates. However, the real-world challenges of implementing TRA-NET have not been thoroughly studied, particularly those related to guide catheter (GC) placement. In this study, we aimed to explore the feasibility and challenges of TRA-NET, with a specific focus on GC placement.

Methods: This retrospective observational study included patients who underwent NET at our institution between December 2019 and May 2022. Procedural success was defined as the successful placement of a GC in the target vessel. Cases in which a Simmons-shaped GC was used or the approach was changed to TFA were classified as difficult. Safety was assessed based on the rate of severe puncture-site complications requiring either blood transfusion or surgical intervention.

Results: Among the 310 patients who underwent NET during the study period, 222 (71.6%) with a median age of 74 years were selected for TRA-NET. The target vessel was in the left anterior circulation (LtAC) in 101 (45.5%) patients, and 8-F GCs were the most frequently used (40.1%). TRA-NET achieved a 95.0% success rate, with a switch to TFA required in 5.0% of the cases. Procedural challenges occurred in 42 (18.9%) patients, primarily in those with LtAC lesions. Specifically, a type III aortic arch (p <0.0001) and age ≥80 years (p = 0.01) were significantly associated with procedural difficulties. Radial artery evaluation was confirmed in 66 cases (29.7%), revealing one instance (1.5%) of radial artery occlusion. No severe puncture-site complications were observed.

Conclusion: TRA-NET may provide substantial therapeutic benefits without significant limitations in device use. However, it may be challenging, particularly in older patients and those with a type III aortic arch with LtAC lesions. Consequently, careful selection of the approach route is imperative.

Keywords: case series; neuroendovascular therapy; radial access.

Fig. 1. Flowchart of cases of procedural difficulty showing initial guide catheter choices and outcomes. This flowchart categorizes the cases encountered in the TRA-neurointervention group based on the initial guide catheter selection and subsequent steps: use of a Simmons-shaped guide catheter as the main guide catheter, use of a Simmons-shaped guide catheter as an inner catheter, or use of a non-Simmons-shaped guide catheter alone, with the transition to TFA after diagnostic angiography at treatment initiation. GC: guide catheter; MC: microcatheter; TFA: transfemoral approach; TRA: transradial approach

Fig. 2. Case showing the use of a Simmons-shaped guide catheter as an inner catheter. (A) Left ruptured posterior communicating artery aneurysm; (B) type III aortic arch; (C) navigation of the diagnostic catheter (arrow); (D) diagnostic catheter herniation into the aortic arch (arrow); (E) use of a Simmons-shaped guide catheter (double arrowhead) as an inner catheter, housed within a non-Simmons-shaped guide catheter (arrowhead) as the main guide catheter; (F) advancement of the main guide catheter to the cervical portion of the left internal carotid artery (arrowhead), facilitated by the Simmons-shaped guide catheter; and (G) post-coil embolization.

Fig. 3. Case showing the use of a Simmons-shaped guide catheter as the main guide catheter. (A) Left carotid artery severe stenosis, (B) type III aortic arch, (C) use of a Simmons-shaped guide catheter (double arrowhead) as the main guide catheter, and (D) post-carotid artery stenting.