Factors Associated With Spinal Cord Ischemia After Thoracic, Abdominal and Thoracoabdominal Endovascular Aortic Repairs

Spinal cord ischemia (SCI) is a challenging complication after endovascular aortic repair throughout the full extent of the aorta. However, data on factors associated with postoperative SCI development that are specific to the treatment extent are scarce. Therefore, we examined factors associated with SCI after thoracic endovascular aortic repair (TEVAR), complex endovascular aortic repair (cEVAR), and thoracoabdominal endovascular repairs (TAARs). All patients who underwent thoracic, abdominal, or TAAR from 2014 to 2019 were identified in the Vascular Quality Initiative linked with Medicare Claims. Procedures were classified into three subgroups based on repair extent: descending thoracic aortic repair (TEVAR), paravisceral segment of the abdominal aorta grouped as cEVAR, and TAAR. Logistic regression was used to identify factors associated with SCI within each group. Cox regression was used to evaluate the impact of SCI on 5-year survival. A total of 6591 patients were included (50% TEVAR, 42% cEVAR, and 8% TAAR). SCI incidence rates were 3.6%, 2.5%, and 11% for TEVAR, cEVAR, and TAAR, respectively. After TEVAR, preoperative renal dysfunction (odds ratio [OR]: 2.5, 95% confidence interval [CI]: 1.6-3.9; P < .001), ruptured presentation (OR: 3.9, 95% CI: 2.0-7.2; P < .001), and more extensive coverage (for each zone covered: OR: 1.5, 95% CI: 1.1-2.1; P = .008) were associated with higher odds of SCI. Left subclavian artery revascularization was associated with lower odds of SCI (OR: 0.48, 95% CI: 0.23-0.95; P = .041) (Table I). After cEVAR, patients with prior open (OR: 2.5, 95% CI: 1.1-5.1; P = .012) and endovascular (OR: 2.3, 95% CI: 1.1-4.8; P = .020) aortic surgery, longer operative times (for each hour: OR: 1.4, 95% CI: 1.2-1.5; P < .001), and more extensive coverage (for each zone covered: OR: 1.2, 95% CI: 1.0-1.4; P = .025) had higher odds of SCI (Table II). Notably, coverage extent and staged repair were not found to be significantly associated with SCI after TAAR (Table III). SCI was associated with higher 5-year mortality among all repairs (TEVAR: adjusted hazard ratio [aHR]: 2.1, CI: 1.6-2.9; P < .001; cEVAR: aHR: 3.4, CI: 2.4-4.7; P < .001; and TAAR: aHR: 2.1, CI: 1.3-3.2; P < .001). The extent of aortic zone coverage was associated with SCI after TEVAR and cEVAR, whereas prior aortic surgery was associated with SCI after cEVAR. Notably, left subclavian artery revascularization was associated with lower odds of SCI after TEVAR. In contrast to previous reports, staged repair was not associated with lower SCI risk after TAAR. Future studies should focus on procedure-specific risk factors to identify patients at higher risk of SCI and understand the optimal preventive strategy within specific procedures.Table ILogistic regression analysis for factors associated with SCI after TEVAR, cEVAR, or TAAACharacteristicTEVARcEVARTAAROR95% CIP valueOR95% CIP valueOR95% CIP valueAge1.000.98-1.0.901.00.99-1.0.111.00.95-1.0.9Gender (female)0.900.59-1.3.600.950.52-1.6.900.660.34-1.2.2White0.910.58-1.4.700.690.37-1.3.200.820.39-1.8.6Hypertension1.80.77-5.1.201.20.51-3.5.700.860.28-3.3.8Smoking history1.30.83-2.2.202.20.84-7.7.151.60.65-4.6.3Prior aortic surgery NoneRef.Ref.Ref.Ref.Ref.Ref.Ref.Ref.Ref. Open0.590.28-1.1.122.51.1-5.1.0121.30.61-2.8.30 Endovascular0.440.17-0.97.0672.31.1-4.8.0200.510.18-1.2.20 Both1.70.41-5.3.401.60.25-6.5.501.10.29-3.6.80COPD1.40.89-2.2.141.10.67-1.9.601.70.90-3.3.10Prior MI1.20.72-2.0.400.840.43-1.5.601.10.46-2.5.80Baseline eGFR <60 mL/min/1.73 m22.51.6-3.9<.0010.960.56-1.6.901.20.67-2.4.40Pathology TAARef.Ref.Ref.Ref.Ref.Ref.Ref.Ref.Ref. Accute dissection1.70.94-3.1.077–––––– CTBAD + PDA1.60.74-3.2.20–––––– Traumatic––––––––– PAU + IMH + (PAU + IMH)1.20.65-2.1.60–––––– Other–––1.40.33-4.6.501.10.50-2.6.70Presentation AsymptomaticRef.Ref.Ref.Ref.Ref.Ref.Ref.Ref.Ref. Symptomatic1.30.77-2.3.301.00.49-2.1.90.830.39-1.7.60 Rupture3.92.0-7.2<.0011.10.26-3.6.82.00.56-6.4.20Total procedure time, hours1.10.99-1.2.0671.41.2-1.5<.0011.00.95-1.2.20Estimated blood loss, 100 mL1.00.98-1.0.201.00.99-1.0.31.041.0-1.08.026Left subclavian artery treatment NoneRef.Ref.Ref.–––Ref.Ref.Ref. Occlusion0.830.43-1.5.50–––0.290.04-1.1.12 Revascularization0.480.23-0.95.041–––0.810.34-1.8.6Celiac involvement Infraceliac sealingRef.Ref.Ref.Ref.Ref.Ref. Supraceliac sealing1.60.90-3.1.110.790.38-1.6.5Hypogastric involvement None–––Ref.Ref.Ref.––– Hypogastric artery involvement–––0.710.14-2.6.6–––Staged aortic treatment––––––0.880.45-1.7.70Length of coverage (zones)1.51.1-2.1.0081.21.0-1.4.0251.050.89-1.2.6cEVAR, Complex endovascular aortic repair; CI, confidence interval; COPD, chronic obstructive pulmonary disease; CTBAD, complicated type B aortic dissection; eGFR, estimated glomerular filtration rate; IMH, intramural hematoma; MI, myocardial infarction; OR, odds ratio; PAU, penetrating aortic ulcer; PDA, patent ductus arteriosus; TAA, thoracic aortic aneurysm; TAAR, thoracoabdominal endovascular repair; TEVAR, thoracic endovascular aortic repair.Boldface P values represent statistical significance. Open table in a new tab