Interaction Between Guiding‐Extension Catheter and Drug‐Eluting Stents: Always Safe or Sometimes Harmful?

ABSTRACT Background Guiding‐extension catheters (GECs) provide enhanced support to guiding catheter (GC) during complex percutaneous coronary intervention (PCI). However, by reducing the inner cross‐sectional diameter, they can create high friction between the GEC and the drug‐eluting stents (DES), potentially causing abrasion and damage to the abluminal struts. Aim This study aims to compare the performances of the Amphilimus Cre8 EVO polymer‐free DES with all the other surface‐coated DES. The abluminal grooves of this polymer‐free DES, which contain the drug and avoid any risk of its abrasion and detachment (abluminal reservoir technology), may offer a protective effect during stent advancement within the GEC. Methods Between January 2019 and April 2024, 218 patients who underwent complex PCI procedures with the insertion of a DES and the use of GEC were enrolled in the study. They were divided into Group A (39 patients) received the Amphilimus polymer‐free DES, while Group B (179 patients) received other types of DES. To evaluate the efficacy and safety of the DES used, a device‐oriented composite endpoint (DoCE) was assessed at one year of follow‐up. This composite endpoint included Cardiovascular Death, Target Vessel Myocardial Infarction, and Clinically and Physiologically indicated Target Lesion Revascularization. Results At the one‐year follow‐up, the primary endpoint demonstrated a statistically significant difference between the two groups. Event‐free survival from DoCE was 97.4% in Group A compared to 85.5% in Group B (Log rank = 0.027). Additionally, there was a significant difference in mean stent length between the groups: Group A had a longer mean stent length of 52.4 ± 38.6 mm, while Group B had a mean length of 40.4 ± 22.6 mm, with a p ‐value of 0.01. All other clinical and procedural variables were similar between the two groups. Conclusion Our findings suggest that the polymer‐free DES tested in this study appears to be the most effective option when using GECs, as it may help prevent negative interactions between the inner surface of GEC and the abluminal struts of the DES.