Characterization of Strokes Following Gore Thoracic Branch Endografting Requiring Zone 2 Landing

Abstract

The GORE® TAG® Thoracic Branch Endoprosthesis (TBE)is the only currently FDA-approved branched device for the treatment of thoracic aortic pathology requiring landing in Zone 2 in the US. While the aneurysm cohort disabling stroke rate in the pivotal trial has previously been reported, a more complete and granular description has not yet been published. This is a descriptive series detailing the neurologic sequelae from the pivotal trial, out to 12 months. All patients underwent Modified Rankin Scale (MRS) assessment at screening, discharge, 1-, 6-, and 12-month intervals. A disabling stroke was defined as occurring within 30-days of the index procedure, combined with a MRS ≥2 with an increase from baseline of at least one grade. Descriptive statistics with important associations with aortic pathology, landing in native aorta versus Dacron graft, and intraoperative ballooning were noted. Further granularity with regard to the distribution and type of stroke are also reported, where available. A total of 238 patients were included in the pivotal trial. The treated aortic pathologies were: aneurysm (n=84), dissection (n=132), traumatic transection (n=9), other isolated lesions(n=13). Through 12 months, the overall stroke rate was 5.9%, with the highest rate of stroke in the aneurysm cohort (aneurysm-8.3%, dissection-4.6%, traumatic transection-0%, other-7.7%). The frequency of disabling strokes through 12 months were: aneurysm-4.3%, dissection-2.3%, other lesion-7.7%. Forty percent of strokes (n=6) occurred within 30 days and included both hemorrhagic (n=3) as well as ischemic (n=3) events. The distribution of strokes within 30 days included left carotid (n=1), posterior circulation (n=2), as well as unknown (n=3). The strokes occurring after 30 days were primarily ischemic (6/8), and included left carotid (n=2), right carotid (n=1), posterior circulation (n=1), posterior circulation and right carotid (n=1), posterior circulation and left and right carotid (n=1), and unknown location (n=1). The majority of patients suffering from stroke had aortic component landing in the native aortic arch, as well as ballooning of the aortic component (10/14). The TBE prosthesis is associated with comparable 30-day stroke rates to similar series of patients undergoing Zone 2 landing after debranching procedures. Stroke rates were highest in aneurysm pathology patients, with no strokes in the traumatic transection cohort. Perioperative strokes were hemorrhagic and ischemic, whereas those occurring after the perioperative period were primarily ischemic in nature. The distribution of stroke covered multiple territories, suggesting an embolic etiology. These data better define the neurologic risks associated with placement of this branched technology in the aortic arch.