Spinal Cord Ischemia following Elective Endovascular Repair of Infrarenal Aortic Aneurysms: A Systematic Review

Background: Spinal cord ischemia (SCI) after abdominal aortic aneurysm (AAA) endovascular abdominal aortic aneurysm repair (EVAR) is a rare but devastating complication. The mechanism underlying the occurrence of SCI after EVAR seems to be multifactorial and is underreported and not fully elucidated. The aim of the study was to investigate the clinical outcomes in patients with this serious complication. Methods: A systematic review of the current literature, as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines, was performed to evaluate the incidence of SCI after elective EVAR. PubMed and Scopus databases were systematically searched. Studies reporting on thoracic endovascular aneurysm repair, open repair of AAAs, and symptomatic or ruptured AAAs were excluded. Results: In total, 18 articles reporting 25 cases were included. The mean age was 74.6 +/- 7.6 (range: 60-90) years. The mean diameter of AAAs was 5.96 +/- 1.0 cm (range: 4.7-8.3). Six cases also had aneurysms in the common iliac arteries. Seventy-one percent of AAAs had characteristics that made EVAR difficult and technically demanding. The mean operative time was prolonged, 254 +/- 104.6 min, and associated with extensive intravascular handling. In 41.6% of cases, additional procedures were performed because of the difficult anatomy. Thirty-two percent of the cases had 1 internal iliac artery (IIA) embolized with coils or covered with the stent graft, and 14% had both IIAs compromised. In most of the cases, SCI symptoms presented immediately after the operation, and in 14.8% of patients, the symptoms had late presentation. Almost all cases had motor loss in the form of paraparesis or paraplegia, 54% of the cases also had diminished sensation, and 29.1% of the cases had urinary and/or fecal incontinence. Heterogeneity was observed regarding the management of the disease; in 6 of the cases, cerebrospinal fluid (CSF) drainage was performed, steroids were administered in 5, and in the other cases, an expectant strategy was selected. In 50% of the cases, only small improvement was seen at follow-up. In 25% of the cases, no improvement was seen, and 25% had almost complete recovery. Conclusions: Our study identified a common pattern among patients who present SCI after EVAR: difficult anatomy, prolonged operative time, additional procedures, and extensive intravascular handling that may have led to embolization. Patency of pelvic circulation preoperatively is also of importance. Regarding outcomes, only 25% of patients recovered, and in certain cases, CSF drainage may have significantly improved chances for recovery.