The study purpose is to present a new technique for fenestrated endovascular aortic aneurysm repair (fEVAR) and to review its preliminary result. With increasing experience and long-term outcomes, there is a trend towards increasingly extensive fEVARs being performed, with four-vessels solution to secure a durable proximal landing zone [1-3]. This approach requires either a 22 Fr contralateral introducing sheaths [4] or multiple access (femoral and brachial) [5] potentially leading to higher access-related complications and lower limb ischemia rates [6-9]. The SiMplified bARe-wire Target vessel (SMART) technique for fEVAR aims to simplify the procedure by avoiding guiding sheaths into visceral arteries during the main graft deployment.

The SMART technique requires a 12-14Fr contralateral introducer (compared to standard 18-22Fr for 3-4 fenestrated EVAR) to achieve target vessel cannulation and stenting during fEVAR, by avoiding the use of parallel 6-7Fr guiding sheaths into each visceral vessel. Fenestrations are sequentially cannulated, assisted by a steerable sheath. A stiff wire is maintained in each fenestration, with a single sheath parked in the final cannulated fenestration while releasing the fenestrated graft. Data on patients treated for pararenal or thoracoabdominal aortic aneurysms with fEVAR adopting the SMART technique were retrospectively reviewed. End points were technical success, intraprocedural variables, mortality, Major Adverse Events (MAEs), and target vessel patency. Kaplan-Meier analysis was used to estimates survival and reintervention rates.

From May 2018 to December 2020, 57 consecutive patients were treated for pararenal or thoracoabdominal aortic aneurysms. Primary technical success was 96.4%. No misalignment occurred from graft deployment. The total number of fenestrations was 169, including 54 left and 53 right renal arteries, 43 superior mesenteric artery and 18 celiac trunk (3.0±0.9 vessels/patient), with target vessel technical success of 98.2%. One celiac trunk dissection and one unsuccessful cannulation of the left renal artery were the cause of technical failures in 2 patients. Three celiac trunks were not intentionally stented, without later endoleak or occlusion. During the first 90 days, there were no deaths (0%). MAEs included AKI in 3 patients (5%) with no new dialysis onset, respiratory failure requiring prolonged ventilation in 2 patients (4%), myocardial ischemia in 1 patient (2%), no lower limb ischemia, stroke or paraplegia occurred. After a mean follow-up of 14±10 months, seven patients died, one of which was aortic-related, resulting in freedom from all-cause mortality at 2 years of 85.1% (95% CI, 75.5-94.7%) and aortic-related mortality of 95.6% (95% CI, 89.7-100%). Primary and assisted primary target vessel patency was 94.6%±1.8% and 97.0%±1.3% respectively. Late reintervention rates was 16% and estimates for freedom from all-cause reinterventions and branch-related reinterventions, respectively 67.8% (95% CI, 49.8-85.8%) and 72.0% (95% CI, 54.0-90.0%) at 2 years follow-up.

The SMART technique proved to be a safe alternative to standard fEVARs with excellent technical result and acceptable target vessel patency at mid-term, while reducing the risk for introducer-induced lower limb ischemia, related complications, and morbidity.

1. Mastracci, T.M., et al., Twelve-year results of fenestrated endografts for juxtarenal and group IV thoracoabdominal aneurysms. J Vasc Surg, 2015. 2. O'Callaghan, A., et al., Type Ia endoleaks after fenestrated and branched endografts may lead to component instability and increased aortic mortality. J Vasc Surg, 2015. 3. Sveinsson, M., et al., Early versus late experience in fenestrated endovascular repair for abdominal aortic aneurysm. J Vasc Surg, 2015. 4. Oderich, G.S., et al., Endovascular repair of thoracoabdominal aortic aneurysms using fenestrated and branched endografts. J Thorac Cardiovasc Surg, 2017. 5. Knowles, M., et al., Upper extremity access for fenestrated endovascular aortic aneurysm repair is not associated with increased morbidity. J Vasc Surg, 2015. 6. Swerdlow, N.J., et al., Stroke rate after endovascular aortic interventions in the Society for Vascular Surgery Vascular Quality Initiative. J Vasc Surg, 2020. 7. Maurel, B., et al., The impact of early pelvic and lower limb reperfusion and attentive peri-operative management on the incidence of spinal cord ischemia during thoracoabdominal aortic aneurysm endovascular repair. Eur J Vasc Endovasc Surg, 2015. 8. Kougias, P., et al., Ischemia-induced lower extremity neurologic impairment after fenestrated endovascular aneurysm repair. J Vasc Surg, 2019. 9. Saratzis, A.N., et al., Impact of Fenestrated Endovascular Abdominal Aortic Aneurysm Repair on Renal Function. J Endovasc Ther, 2015.