LAUSR

OBJECTIVE Staged aortic aneurysm repair is one method employed to decrease the risk of spinal cord ischemia (SCI) following endovascular aortic intervention. Sequential sacrifice of arteries perfusing the spine may allow for improved spinal perfusion through the development of collateral networks over time. To evaluate the impact of staging endovascular aortic aneurysm repairs on SCI we conducted a conservative analysis of Vascular Quality Initiative (VQI) data. METHODS De-identified VQI data was queried for cases of endovascular thoracic and thoracoabdominal aneurysm repairs from year 2014 - 2019. Cases were selected based on inclusion criteria: aneurysmal disease, no ruptures, no prior aortic surgeries, no retreatments, and only cases with complete data on aortic zones and SCI. Chi-square, Student's T-tests, and Mann-Whitney U tests were used for univariable analyses, as appropriate. Logistic regression analyses were used to identify independent predictors of outcome. RESULTS There were 116 staged aortic repairs (8.2%) performed out of a total of 1421 endovascular aortic repairs that fit study criteria. The overall rate of SCI within the study cohort was 3.4% (n=48). The distribution of staged aortic repairs and SCI events according to aortic zone coverage are displayed in Table 1. Patients who underwent staged endovascular aortic repairs had higher rates of SCI, pre-op spinal drain placement, non-African American race, COPD, smoking history, positive stress tests, aspirin and statin use, increased estimated blood loss, physician modified endografts, number of aortic zones covered, lower pre-op hemoglobin levels, larger aneurysm sac size, fusiform aneurysms, and longer total procedure times, Table 2. After adjusting for factors associated with SCI, a priori, and factors with a P<0.1 univariable analysis, staged aortic repair was not associated with SCI (odds ratio [OR]=1.86, 95% confidence interval [CI]=.77 - 4.50, P=.17). Of the six factors associated with SCI on univariable analysis, only procedure time ≥6 hours (OR=2.49, 95% CI=1.09 - 5.70, P=.031) and the number of aortic zones covered (OR=1.15, 95% CI=1.00 - 1.32, P=.047) were predictive of SCI. Staged repairs had a lower proportion of permanent SCI (38%, 3 of 8 cases) compared to repairs that were not staged (68%, 27 of 40 cases), with a relative risk reduction of 44% for those who developed SCI, P=0.21. CONCLUSION In a large national dataset, staged aortic repairs were performed for patients with more extensive aortic disease. Staged aortic repairs were only performed in about 8% of cases and the rate of SCI remained low. After adjusting for baseline comorbidities, extent of aortic disease, and other factors that may potentiate SCI, staged aortic aneurysm repair had a similar risk of SCI compared to non-staged repairs. However, there was a trend toward decreased permanent SCI risk in the staged aortic repair group.