Perioperative Outcomes of Carotid–Subclavian Bypass or Transposition versus Endovascular Techniques for Left Subclavian Artery Revascularization during Nontraumatic Zone 2 Thoracic Endovascular Aortic Repair in the Vascular Quality Initiative

Background: The aim of our study is to examine the perioperative outcomes of carotid–subclavian bypass or transposition (CS-BpTp) versus endovascular techniques (ETs) for left subclavian artery (LSA) revascularization during nontraumatic zone 2 thoracic endovascular aortic repair (TEVAR). Methods: We used prospectively collected data from the Society for Vascular Surgery Vascular Quality Initiative (VQI) to identify patients who had undergone TEVAR at participating centers (2013–2018). Patients were eligible for inclusion if they had undergone nontraumatic zone 2 TEVAR and concomitant LSA revascularization. Our main exposure of interest was LSA revascularization technique, CS-BpTp, or any ET. If a patient underwent multiple TEVAR procedures during the study period, the first case involving zone 2 was used for analysis. Preoperative patient characteristics were reviewed between treatment groups. The primary outcomes were mortality, transient ischemic attack (TIA)/stroke, and spinal cord ischemia (SCI). All outcomes were assessed up to 30 days postoperatively. Results: A total of 837 patients were included in the study. The pathologies most frequently treated were aneurysm in 248 (34%) and dissection in 326 (45%). Overall, 721 subjects (86%) underwent CS-BpTp while 116 subjects (16%) underwent ETs. The latter included the following techniques: 23 chimney grafts, 3 scallops, 15 fenestrated grafts, and 75 branched grafts. Mortality was equal at 3% for both groups (P = 0.67). The rate of TIA/stroke was not significantly different in both groups (5.5% vs. 5%, P = 0.78). Similarly, the rate of SCI was 3% in the entire cohort without significant differences seen between treatment groups (P = 1). Multivariate logistic regression could not identify either CS-BpTp or ETs as independent predictors for death or TIA/stroke. Conclusions: Within VQI, LSA revascularization during nontraumatic zone 2 TEVAR is safely and effectively achieved with either CS-BpTp or ETs across all nontraumatic thoracic aortic diseases. These techniques appear to be associated with similar perioperative outcomes in selected patients with low rates of mortality and major neurologic morbidity. Although no differences were seen in the proportion of early type I or III endoleaks, further prospective studies are warranted to elucidate the long-term durability of ETs compared with CS-BpTp.