What role should EBU catheters play in the interventional approach to anomalous right coronary arteries? A case series.

Abstract

Percutaneous coronary intervention (PCI) for anomalous right coronary artery (ARCA) remains technically challenging due to variable ostial anatomy. The Extra Back-Up (EBU) catheter, although designed for left coronary interventions, may offer advantages in ARCA PCI, but its performance across anatomical subtypes is not well defined. This single-center retrospective case series included 17 patients (2019-2024) with ARCA from the left coronary sinus or with high take-off anatomy, in whom an EBU catheter was used. Fourteen patients underwent PCI, one had fractional flow reserve (FFR)-only assessment, and two underwent diagnostic angiography alone. Anatomical subtypes were: Type A (ostium above left coronary artery [LCA]), Type B (below LCA), Type C (midline), or high take-off (≥10 mm above sinotubular junction). Primary outcomes were procedural success (stable engagement, full device delivery, no catheter exchange) and safety. Procedural success with the EBU catheter was 100% in Type A (2/2) and 83.3% in Type B (5/6) when used as the initial guide. In Type C and high take-off anatomies, success was achieved in one of two cases each. EBU was also employed as a second-choice catheter in five patients(one Type A, three Type B, one high take-off) after failed engagement with standard guides catheters. No catheter-related dissections occurred. One minor in-hospital complication (5.9%) and one patient required unplanned re-intervention within 30 days. In this descriptive series, the EBU catheter was successfully employed as a primary or rescue tool in a majority of select ARCA cases, with the highest success in Types A and B. These observations, while not comparative, suggest it is a viable option in the operator's arsenal for these challenging anatomies and warrant further prospective evaluation.