Examination of a large collective combined with individual case analyses may give new insights into mechanisms and prevention of spinal cord ischemia (SCI) after thoracic endovascular repair.Methods
In an 11-year period, stent-grafts were implanted in 406 patients for various aortic pathologic conditions. The mean age was 63 years (15–91 years) and 300 (74%) patients were men; 58 patients underwent staged thoracic stent-graft procedures. The length of aorta covered was between 75 and 584 mm (mean, 204 mm). Thoracoabdominal branched or fenestrated stent-grafts were implanted in 11 patients. The left subclavian artery was occluded in 161 patients (39%); this occurred in half of them (n = 78) after protective revascularization. Prophylactic cerebrospinal fluid (CSF) drainage was used selectively in 4 cases; no neuromonitoring was used.Results
The incidence of SCI was 2.7% (n = 11); 6 patients (1.5%) had major permanent deficits. Conditions that had a potential influence on SCI were analyzed. Statistical correlation was found for previous conventional or endovascular abdominal aortic aneurysm repair (odds ratio [OR], 4.8), coverage of the entire descending thoracic aorta (OR, 3.6), and implantation of thoracoabdominal branched and fenestrated stent-grafts (OR, 9.5). Individual analyses revealed other conditions that might have played a role, such as embolization into the segmental arteries, severe visceral ischemia, profound hemorrhagic shock, and heparin-induced thrombocytopenia.Conclusions
The incidence of SCI is unexpectedly low despite extensive sacrifice of intercostal arteries. Extended coverage of the thoracic and thoracoabdominal aorta seems to have a higher risk, but other factors may contribute to the individual disaster.