Risk of Spinal Cord Ischemia After Treatment of Complex Aortic Aneurysms with Fenestrated or Branched Devices

Abstract

Introduction -The aim of our study was to analyze the incidence of spinal cord ischemia (SCI) in patients presenting with complex aortic aneurysms treated with fenestrated (F-EVAR) and branched endovascular aortic aneurysm repair (B –EVAR), and identify risk factors associated with this complication. Methods - A retrospective study of prospectively collected data was undertaken including patients presenting with complex aortic aneurysm (para-renal and thoraco-abdominal; TAAA) treated with the F-EVAR or B-EVAR. The primary end point was the incidence of SCI and the assessment of any associated factors. Results - Between January 2011 and August 2017, a total of 243 patients (mean aneurysm diameter and age of 65.2±15.3mm and 72.4±7.5 years, respectively; 73% males) were treated with F-EVAR or B-EVAR. Asymptomatic patients presented in 73% (177/243) (in contrast to 27%; urgent) and in 52% (126/243) were treated for TAAA (in contrast to 48%; pararenal AAA). F-EVAR (mean number of fenestrations 3.3/case) or B-EVAR (mean number of branches 3.7/case) were undertaken in 67% (164/243) and 33% (79/243), respectively. The total incidence of SCI was 17.7% [43/243; paraplegia in 4% (10/243), paraparesis in 13.7% (33/243)]. Most of the patients with SCI presented immediate post-operative symptoms (72%; 31/43). Spinal drainage had been preoperatively placed in 53% (130/243) and was associated with the prevention of SCI (SCI with spinal drainage 12%; 16/130 vs. SCI without spinal drainage, 24%; 27/113, P=.018). The 30-day mortality rate was 9% (21/243). After multiple logistic regression analysis, SCI was associated with pre-operative renal function (SCI with pre-operative GFR<60, OR 2.43; 95% C.I. 1.18 – 4.99, P= .016) and number of vertebral segments covered (SCI with higher position of proximal stent in terms of vertebra, OR 1.2; 95% C.I. 1.1 – 1.3, P= .000). Similar outcome derives when height of proximal end of stent graft is replaced by total length of aortic coverage. (SCI with pre-operative GFR<60, OR 2.36; 95% C.I. 1.11 – 5.00, P= .025 and with longer length of aortic coverage, OR 1.01; 95% C.I. 1.003 – 1.009, P= .000). Conclusion - The majority of SCI after F-/or B-EVAR of complex aortic aneurysms present immediate post-operatively. The use of preoperative spinal drainage may prevent SCI. Patients with GRF <60 mL/min/1.73 m2 and with longer aortic length stent graft coverage are at higher risk SCI.