Risk factors for spinal cord ischemia after endovascular repair of thoracoabdominal aortic aneurysms

Abstract

The introduction of fenestrated and multibranched endografting transformed the treatment paradigm of patients with thoracoabdominal aortic aneurysms (TAAAs). However, despite the minimally invasive character of the procedure, spinal cord ischemia (SCI) remains a devastating complication. The aim of this study was to address the SCI rates after endovascular TAAA repair and to analyze potential risk factors leading to this complication. A consecutive cohort of patients with nonruptured TAAAs treated by means of fenestrated and multibranched endografting between January 2010 and September 2014 was analyzed. Neurologic examination was routinely performed by an independent neurologist before operation and at discharge. The main outcome measure was the onset of SCI (paraplegia or paraparesis). Secondary outcomes were neurologic complications associated with cerebrospinal fluid drainage (CSFD) and 30-day mortality. Finally, a multivariate regression analysis identified risk factors for SCI. A consecutive 142 patients with TAAAs (Crawford type II, n = 54 [38%]; type III, n = 76 [54%]; type IV, n = 12 [8%]) were included in this study. The majority of patients (n = 129 [91%]) were treated for an atherosclerotic aneurysm, whereas 13 patients (9%) were treated for a postdissection aneurysm. The mean maximal aortic diameter was 65 ± 13 mm. SCI developed in 23 patients (16%; paraplegia in 12 [8%] and paraparesis in 11 [8%]). Of these 23 patients, 10 patients (43%) showed the neurologic deficit directly after the procedure, 11 patients (48%) in the first 24 hours, and 2 patients (9%) after 24 hours. There was an improvement of the neurologic status in the majority of patients, with only three patients (2%) showing irreversible paraplegia at discharge. There was no difference in the 30-day mortality between patients with and without SCI (no SCI, n = 3 [3%] vs SCI, n = 1 [4%]; P = .511). Prophylactic use of CSFD before the procedure was performed in 64 patients (45%), and among them, 4 patients (6%) developed a CSFD-associated complication. No clinical benefit for patients receiving prophylactic placement of CSFD was found (P = .498). The multivariate analysis revealed the percentage of thoracic aortic coverage as the only significant risk factor for SCI (odds ratio, 1.03; 95% confidence interval, 1.01-1.05; P = .001). The SCI rate after endovascular repair of TAAA was 16%, with 8% of those patients suffering from paraplegia. Prophylactic use of CSFD could not reduce the SCI rate and was associated with 6% adverse events. The percentage of thoracic aortic coverage was the most powerful determinant of SCI in these series.