Impact of High-Risk Features and Timing of Repair for Acute Type B Aortic Dissections

Abstract

The new Society for Vascular Surgery reporting standards for type B aortic dissection (TBAD) categorize clinical presentations of aortic dissection into uncomplicated, high-risk features (HRFs) and complicated groups. Although it is accepted that complicated dissections require immediate repair, the optimal timing of repair for those with HRFs has yet to be established. We aimed to identify the ideal timing of thoracic endovascular aortic repair (TEVAR) for HRFs and the outcomes associated with specific HRFs. The Vascular Quality Initiative was queried for TEVARs performed for acute and subacute TBAD with HRFs from 2014 to 2020. Rupture, malperfusion, and uncomplicated cases were excluded. HRFs were defined per the Society for Vascular Surgery guidelines as refractory hypertension, pain, and rapid aneurysm expansion or aneurysm size >40 mm. The primary outcomes were in-hospital or 30-day mortality and 1-year survival, with primary exposure variables of the interval (in days) from symptoms to repair and the number of HRFs. The secondary outcomes were spinal cord ischemia, myocardial infarction, stroke, and retrograde type A dissection. Of the 1100 patients who met the inclusion criteria, 811 had one HRF, 249 had two, and 40 had three. No significant differences were found in the primary or secondary outcomes according to the number of HRFs. Of the 1100 patients, 309 had undergone repair at 0 to 2 days, 262 at 3 to 6 days, 270 at 7 to 14 days, and 259 at ≥15 days. TEVAR performed at ≥15 days was independently associated with lower in-hospital and 30-day mortality (odds ratio, 0.38; P = .0388) and improved 1-year survival. Postoperative stroke was associated with earlier repair (0-2 days). No association was found between the timing of repair with myocardial infarction, spinal cord ischemia, retrograde type A dissection, or reintervention (Tables I and II). TEVAR for TBAD with HRFs delayed for ≥15 days from symptom onset was associated with improved survival, supporting the theory that it is best to delay TEVAR to the subacute phase. Additionally, TEVAR delayed ≥3 days was associated with a decrease in stroke. The presence of more than one HRF was not associated with worse outcomes. Because the classification of HRF is relatively new and without guidelines regarding repair, the present results highlight the risks of early intervention for patients with HRFs and suggest that these patients will benefit from at least a short stabilization period before TEVAR.Table IUnivariate analysis of impact of timing and HRFs on outcomes after TEVARVariableResultsP valueHRF1 (n = 811)2 (n = 249)3 (n = 40)NA Spinal cord ischemia42 (5.2)8 (3.2)3 (7.5).32 Myocardial infarction15 (1.9)1 (0.4)1 (2.5).17 Stroke49 (6)11 (4.4)2 (5).61 Retrograde type A dissection14 (1.7)4 (1.6)0 (0).99Interval to repair, days0-2 (n = 309)3-6 (n = 262)7-14 (n = 270)≥15 (n = 259) Spinal cord ischemia22 (7.1)8 (3.1)11 (4.1)12 (4.6).12 Myocardial infarction5 (1.6)4 (1.5)4 (1.5)4 (1.5).99 Stroke34 (11)11 (4.2)11 (4.1)6 (2.3)< .0001 Retrograde type A dissection4 (1.3)5 (1.9)3 (1.1)6 (2.3).69HRF, High-risk feature; TEVAR, thoracic endovascular aortic repair.Data presented as number (%).Boldface P values represent statistical significance. Open table in a new tab Table IIMultivariate analysis of impact of operative timing and HRFs on outcomesVariableRelated reinterventionIn-hospital/30-day mortalityOR95% CIP valueOR95% CIP valueInterval to repair 0-2 DaysRefRef 3-6 Days0.7440.38-1.455.38711.0150.499-2.063.9674 7-14 Days0.740.38-1.442.37690.4650.199-1.083.076 ≥15 Days0.5580.272-1.142.11040.380.152-0.951.0388HRFs 1RefRef 20.9840.54-1.79.9571.7250.9-3.307.1005 30.9310.21-4.121.92451.7890.465-6.876.3972CI, Confidence interval; HRF, high-risk feature; OR, odds ratio; Ref, reference.Boldface P values represent statistical significance. Open table in a new tab