A systematic review and meta-analysis of the occurrence of spinal cord ischemia following endovascular repair of thoraco-abdominal aortic aneurysms.

Abstract Objective The rates of endovascular repair of thoracoabdominal aortic aneurysms (TAAA-ER) have increased considerably in the last years. While mortality and morbidity rates have improved, spinal cord ischemia (SCI) rates have not declined significantly. The aim of this systematic review and meta-analysis was to examine SCI rates with respect to the efficacy of the different approaches. Methods Cohort studies and case series (>20 patients) reporting SCI rates after TAAA-ER were eligible for inclusion. The primary outcome was the evaluation of SCI. Moderators considered were primarily the staged/non-staged approach, the use of cerebrospinal fluid drainage (CSFD) and TAAA extension. Permanent SCI and mortality rates were extracted. Results Twenty-seven studies (n=2333 patients) were included in the meta-analysis. The pooled estimate for SCI was 11% (95% confidence interval [CI]: 8%-15%; I2:80%). For extent I,II,III and V TAAA, the pooled SCI rate was 13% (95% CI: 10%-17%; I2=71%), while for extent IV TAAA it was 6% (95% CI: 3%-10%; I2=62%). A staged TAAA-ER approach was used in 18 studies and a non-staged approach in 6 (one study included both). A lower pooled SCI rate was identified following staged compared with non-staged TAAA-ER (9% vs. 18%, respectively; P=.02). Staging was accomplished in >1 month in 9 studies and ≤1 month in 2, leading to similar SCI rates (7% vs. 11%, respectively; P=.29). The method of staging (thoracic-endoprosthesis or temporary aortic sac perfusion) did not affect SCI rates. Symptomatic CSFD was associated with a similar pooled rate of SCI compared with prophylactic CSFD (10% vs. 10%, respectively; P=.95). Pooled permanent SCI was 5% (6% following extent I,II,III and V TAAA; 3% following extent IV TAAA). Prophylactic or symptomatic CSFD have a similar rate of SCI (10% vs. 10%, respectively; P=.89). The pooled rate of 30-day mortality was 7%, with a similar incidence for the staged and non-staged approaches (6% vs. 9%, respectively). The inter-stage mortality was reported in 10 studies, with a pooled estimate rate of 1.6%. Conclusions SCI occurs in 11% of TAAA-ER and half of these cases are permanent. A staged approach can reduce SCI rates independently from the timing and the method adopted. The overall mortality rate for staged TAAA-ER is 6%, with one fourth of deaths (1.6%) occurring between stages.