ObjectiveTo evaluate the technique and outcomes of intentional occlusion of directional branches (DBs) using endovascular plugs during branched endovascular aortic repair using off-the-shelf Zenith t-Branch thoracoabdominal (TAAA) stent grafts. MethodsWe reviewed the clinical data and outcomes of all consecutive patients treated by branched endovascular aortic repair using off-the-shelf Zenith t-Branch TAAA stent-graft (Cook Medical, Bloomington, Ind) in seven academic centers from 2013 to 2019. All patients had at least one DB intentionally occluded using extension of the branch with balloon or self-expandable covered stent, followed by placement of endovascular plugs. Intentional occlusion was indicated in patients with variations in the normal four-vessel renal-mesenteric anatomy, pre-existing dialysis, or in those who failed catheterization of a target vessel. End points were 30-day/in-hospital mortality, major adverse events, secondary interventions, target artery (TA) patency, TA instability, and patient survival. ResultsThere were 100 patients, 65 male and 35 female, with median age of 71 years (interquartile range [IQR], 66-75 years). Of these, 31 patients (31%) had urgent/emergent operations for symptomatic/contained ruptured aneurysms. The median aneurysm diameter was 72 mm (IQR, 61-85 mm). A total of 290 renal-mesenteric arteries were incorporated with a median of three (IQR, 3-3) vessels/patient. Indications for DB occlusion were less than four suitable renal-mesenteric targets in 84 patients or pre-existing dialysis and inability to catheterize a target vessel in eight patients each. There were 110 DBs occluded by vascular plugs, including 48 celiac axis, one superior mesenteric artery, and 61 renal DBs. Thirty-day/in-hospital mortality was 10%, including 9% for elective and 13% for urgent/emergent procedures. Major adverse events occurred in 44 patients (44%), including acute kidney injury in 19 patients (19%), estimated blood loss >1 L in 12 patients (12%), respiratory failure and new onset dialysis in six patients (6%) each, bowel ischemia in five patients (5%), and myocardial infarction and paraplegia in two patients (2%) each. The median follow-up was 5 months (range, 1-13 months). Eighteen patients (18%) required secondary interventions, none for problems related to the occluded DB. There were no endoleaks related to the occluded DB. At 2 years, primary and secondary patency and freedom from TA instability were 93% ± 3%, 97% ± 2%, and 91% ± 4%, respectively. Freedom from secondary interventions and patient survival were 75% ± 6% and 63% ± 7%, respectively. ConclusionsIntentional occlusion of DBs using endovascular plugs allows versatile use of a four-vessel off-the-shelf multi-branched TAAA stent graft in patients with variations in the normal renal and mesenteric anatomy or when technical difficulties prevent successful target vessel stenting. There were no endoleaks or secondary interventions associated with the occluded DB.