Protagoras 3.0: feasibility of current fenestrated endografts and chimney technique for complex abdominal aortic aneurysms.

BACKGROUND: The aim of this study was to evaluate the anatomical feasibility of current available fenestrated endografts (FEVAR) and on-label chimney technique (EnChEVAR) in patients with complex abdominal aortic aneurysms (C-AAA). METHODS: Feasibility of EnChEVAR (Endurant II/IIS CE-marked [Medtronic]) and 4 types of FEVAR (Zenith Fenestrated CE-marked, Zenith Fenestrated Low-Profile [LP] custom-made device [CMD] [Cook Medical], Fenestrated Anaconda LoPro90 CMD, Fenestrated Treo CMD [Terumo Aortic]) was assessed according to the manufacturer's instructions for use. Computed tomography angiograms of patients with C-AAA previously included in the Protagoras 2.0 study were retrospectively reviewed. The aortic coverage was ideally planned to involve a maximum of two chimney grafts or fenestrations. RESULTS: Iliac access and aortic neck of 73 C-AAAs were analyzed. The overall feasibility was significantly different between EnChEVAR (33%) and FEVAR (Zenith Fenestrated 15%, Zenith Fenestrated LP 15%, Fenestrated Anaconda LoPro90 45%, Fenestrated Treo 48%). The iliac access feasibility was significantly lower for Zenith Fenestrated with standard profile compared to all other grafts. The aortic neck feasibility was significantly higher for EnChEVAR and both Terumo Aortic fenestrated stent grafts, compared to both Cook Medical grafts. The treatment using any of the three current available fenestrated grafts with lower profile (Zenith Fenestrated LP, Fenestrated Anaconda LoPro90, Fenestrated Treo) would have been feasible in 71% of the cases. CONCLUSIONS: Most of the patients treated by ChEVAR would have not been treated by first generation fenestrated stent graft. The current available fenestrated endografts, with lower profile and suitable also for angulated necks, increase the anatomical feasibility.

Intravascular Iliac Artery Lithotripsy to Facilitate Aortic Endograft Delivery: Midterm Results of a Dual-Center Experience.

PURPOSE: To assess the feasibility and safety of intravascular lithotripsy (IVL) for enabling transfemoral abdominal (EVAR), thoracic (TEVAR), and thoracoabdominal (BEVAR) endovascular aneurysm repair in patients with narrow and calcified iliac arteries. MATERIALS AND METHODS: Consecutive patients treated with IVL for severe calcified and narrowed iliac access before EVAR, TEVAR, or BEVAR between November 2020 and June 2022 were retrospectively evaluated. All anatomical iliac characteristics were acquired by multi-planar reconstruction of preoperative computed tomography angiography (CTA). The hostility of the vascular accesses was classified based on Peripheral Arterial Calcium Scoring System (PACSS) and calcified access severity score (CASS), a new score considering both anatomical (calcium grade and length, minimum lumen diameter [MLD], and tortuosity index) and aortic stent-graft (SG/MLD index) parameters. Primary endpoint was technical success defined as successful aortic endograft delivery and deployment without iliac rupture. Freedom from complications and primary patency were additionally analyzed. RESULTS: Twenty-eight iliac axes were treated with IVL (8 bilateral) in 20 patients (mean age 74.5±6.7 years) with a mean follow-up of 26.5±6.2 (range 17-36) months. Ten patients underwent EVAR: 3 TEVAR, and 7 BEVAR procedures. In 14 patients (70%), aneurysm disease was associated with symptomatic aorto-iliac occlusive disease (AIOD), with Rutherford class III to IV. The PACSS was grade IV in 89% of the cases and the CASS (mean 14±2) was grade III to IV in all cases. The stent-graft (SG) outer diameter (5.60±1.65 mm) was significantly larger by 50% than MLD (3.96±1.20 mm), with an SG/MLD index of 1.50±0.51 (p<0.001). Technical success was 100%. No dissection, rupture, or distal embolization occurred. One (3.4%) bail-out stenting was necessary as endoconduit after IVL treatment. One month CTA showed that postoperative luminal gain increased by 93% (p<0.001). An improvement of 2 Rutherford classes occurred in all AIOD patients with a primary patency of 100% at last follow-up. CONCLUSIONS: This study shows the safety and feasibility of IVL as a valuable option to treat narrow and calcified iliac arteries to facilitate endograft delivery. Further studies will be useful to confirm these results. CLINICAL IMPACT: In this article, the use of intravascular iliac artery lithotripsy to facilitate aortic endograft delivery is explored. The presence of iliac severe calcifications still represents a contraindication for aortic endovascular repair. Intravascular lithotripsy increases the feasibility and safety of endovascular aortic procedures, facilitating endograft delivery and reducing the risk of iliac rupture and/or dissections by improving vessel compliance and luminal gain. This novel vessel preparation could be an alternative to "paving and cracking" and/or iliac conduits. This study describes a new score to classify the severity of iliac calcifications, considering anatomical parameters and the profile of aortic endografts delivery system.

Extravascular Ultrasound (EVUS) to Assess the Results of Peripheral Endovascular Procedures.

Contrast arteriography (CA) is considered the gold standard to evaluate any phase in peripheral arterial disease (PAD) interventions, from diagnostics to final results. Nevertheless, duplex ultrasonography (DUS) mostly used for the pre/postoperative phase and follow-up control, could be a potential intraoperative adjunctive imaging tool to assess the effects of endovascular revascularization in patients with iliac and femoropopliteal lesions. The PAD "duplex-assisted" protocol includes a preoperative DUS control followed by an intraoperative and a postoperative control. The most important parameters are pulsed doppler spectral analysis and waveform changes, which are impossible to detect with intravascular ultrasound (IVUS). By using a similar acronym, the intraoperative DUS has been previously described as extravascular ultrasound (EVUS). B-mode imaging, color flow, and peak systolic velocity (PSV) are considered. EVUS could be very useful to evaluate the effects of endovascular treatment, mainly in cases of unclear CAs, severe calcifications and/or dissections. In the context of the "leaving nothing behind" strategy, EVUS can drive the physician to evaluate the absence of flow-limiting dissections and decide which target lesion should be treated with antirestenotic therapy, further vessel preparation, or stenting. The EVUS protocol could be a safe and feasible option to improve the completion assessment of endovascular PAD treatment. A better ultrasound waveform is a sign of improved luminal gain and compliance, which is extremely important to finalize the results of new peripheral device technology, such as intravascular lithotripsy.