LAUSR

OBJECTIVE The new Society for Vascular Surgery/Society for Thoracic Surgery reporting standards for type B aortic dissection (TBAD) categorize clinical presentations of aortic dissection into uncomplicated, high-risk features (HRF), and complicated groups. While it is accepted that complicated dissections require immediate repair, the optimal timing of repair for HRF has yet to be established. This study aims to identify the ideal timing of thoracic endovascular aortic repair (TEVAR) for HRF, as well as outcomes associated with specific HRF. METHODS The Vascular Quality Initiative was queried for TEVARs performed for acute and subacute TBAD with HRF from 2014 - 2020. Rupture, malperfusion and uncomplicated patients were excluded. HRF were defined per the guidelines as refractory hypertension, pain, or rapid expansion/aneurysm > 40mm. The primary outcomes were in-hospital/30-day mortality and 1-year survival with primary exposure variables being days from symptoms to repair and number of HRFs. Secondary outcomes were spinal cord ischemia (SCI), stroke, and retrograde type A dissection (RTAD). RESULTS Of the 1,100 patients who met inclusion criteria, 811 had one high-risk feature, 249 had two and 40 had three. There were no significant differences in primary or secondary outcomes based on number of HRFs. 309 patients underwent repair at 0-2 days, 262 at 3-6 days, 270 at 7-14 days and 259 at ≥ 15 days. TEVAR performed at ≥ 15 days was independently associated with lower in-hospital/30-day mortality (OR=0.38, P=.0388) and improved 1-year survival (Figures 1, 2). Postoperative stroke was associated with earlier repair (0-2 days). There was no association of timing of repair with SCI, RTAD or reintervention (Tables 3, 4). CONCLUSIONS TEVAR for TBAD with HRF delayed at least 15 days from symptom onset is associated with improved survival, supporting the theory that it is best to delay TEVAR until the subacute phase. Additionally, TEVAR delayed at least 3 days is associated with a decrease in stroke. Having more than one HRF was not statistically associated with worse outcomes. As the classification of HRF is relatively new and without guidelines for repair, this study highlights the risks of early intervention for HRF and suggests that these patients appear to benefit from at least a short stabilization period prior to TEVAR.