Analysis of cutting ballon versus plain balloon dilatation after electrified wire in situ fenestration

Objective Electrified wire in situ fenestration (EW-ISF) has been recently described both in vivo and in vitro as a feasible alternative to laser ISF to address complex aortic pathologies in emergency situations. However, no data are currently available regarding the preferred dilatation method after puncture. The aim of this paper was to compare two established schemes of fenestration dilation after an EW-ISF setting. Methods A total of 72 EW-ISFs were performed in 4 commercially available endografts: Zenith Alpha (n = 20), RelayPro (n = 20), Endurant IIs (n = 20), and Valiant Captivia (n = 12). In group A, fenestrations were sequentially dilatated with a 2-mm and a 6-mm plain balloon dilatation (PBD). In group B, fenestrations were dilatated with a 2-mm PBD, a 4-mm cutting balloon, and a 6-mm PBD. Postdilatation fenestration morphological features were analyzed, and diameters and surface were measured after dilatation and after 24 hours to assess the relative fabric elastic recoil. For each graft, in both group one bridging stent (BS) was implanted and its caliber measured with intravascular ultrasound. Results In both the Zenith and the Endurant, group B showed more tearing (P = .302 and P < .001 respectively), less bulging (P = .039 and P < .001), and more frequent slit-like fenestration morphology (P = .015 and P = .001). The Valiant graft displayed major (>0.5 cm long) tearing in group B. Fenestration dimensions and recoil momentum were comparable between the two groups in all grafts, but the Endurant, where group B fenestrations had significantly higher fenestration area (6.5 mm2 vs 2.3 mm2; P < .001). BS caliber was comparable in both groups in the RelayPro and Zenith Alpha, but a significant stenosis was assessed in group A in the Endurant IIs. Conclusions Both cutting balloon dilatation and PBD are feasible and comparable after EW-ISF in the in the RelayPro and the Zenith grafts. Cutting balloon provides more ideal fenestration dimensions in the Endurant IIs and might be preferred. It determines excessive damages in the monofilament graft and should, therefore, be avoided. Clinical Relevance Electrified wire in situ fenestration is an emerging, low-cost alternative for urgent aortic branch revascularization, but optimal postfenestration dilation remains undefined. This study provides practical guidance on balloon selection according to graft fabric. Cutting balloons may improve fenestration enlargement and reduce the risk of bridging stent stenosis in multifilament grafts such as Endurant IIs, while causing excessive damage in monofilament devices. Tailoring dilation strategy to graft type may enhance safety, durability, and procedural success in emergency endovascular aortic repair.