T-branch by partial deployment technique in the endovascular repair of complex aortic and thoracoabdominal aneurysms with narrow or severe angulated para-visceral aorta

Objective: The partial deployment technique (PDT) is an unconventional option of T-branch deployment to allow target arteries (TAs) cannulation/stenting from the upper arm access, in case of narrow (NPA <25 mm) or severely angulated (APA >60°) aorta. Aim of this study was to report outcomes of the endovascular repair of complex aortic (c-AAAs) and thoracoabdominal (TAAAs) aneurysms by T-branch and PDT. Methods: All consecutive patients underwent urgent endovascular repair of c-AAAs and TAAAs by T-branch (Cook Medical) and PDT from 2021 to 2023 were analyzed. Technical success (TS), 30-day mortality, and TA instability within 30 days and 1 year, as well as reinterventions, were assessed as primary endpoints. Time of intraoperative pelvic/lower limb ischemia, spinal cord ischemia (SCI), and perioperative stroke were assessed as secondary endpoints. Results: Thirty-three cases were analyzed. There were six type I endoleaks (18%) in failed endovascular aortic repair, nine juxta/para-renal aneurysms (28%), six post-dissection TAAAs (18%), and 12 degenerative TAAAs (36%), respectively. The median para-visceral aortic lumen diameter was 23 mm (interquartile range [IQR], 19-27 mm), and 10 cases (30%) had APA. Of 128 TAs, 111 (87%) were cannulated/stented with distally captured aortic graft. The median time of pelvic/lower limb ischemia was 120 minutes (IQR, 90-150 minutes). TS was achieved in all patients. One patient (3%) suffered SCI, and there were no cases of stroke. An asymptomatic renal artery occlusion was detected at postoperative imaging, which was recanalized by thrombus-aspiration/relining. This was the only case of TA instability (1/128; 0.8%) and reintervention (1/33; 3%) within 30 days. Two patients (6%) died within 30 days. Median follow-up was 14 months (IQR, 6-22 months). One case (3%) of bilateral renal artery occlusion occurred at 6 months. No superior mesenteric artery or celiac trunk events occurred, with an overall TA instability rate of 2% (3/128). Eighteen patients (55%) completed the radiologic follow-up at 1 year with no new cases of TA instability. Freedom from TA instability was 91% at 1 year. Conclusions: T-branch by PDT seems to be safe and effective in the management of c-AAAs/TAAAs with NPA or APA. Results were satisfactory in terms of TS and mid-term TA instability, suggesting a possible enlargement of the anatomical feasibility criteria for outer branches in urgent cases.