Association between aortic coverage and spinal cord ischemia after endovascular repair of type B aortic dissection

Objectives: To examine the association between aortic coverage and occurrence of spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection.

Methods: Thirty-eight consecutive patients (mean age 52 years; 35 men) who underwent TEVAR for type B aortic dissection at our centre were included. Patients were stratified into two groups based on stent graft length (SGL): group I (≤ 200 mm; n = 19) and group II (> 200 mm; n = 19). All the procedures were performed under strict blood pressure monitoring. Preoperative cerebrospinal fluid (CSF) drain was instituted in two patients.

Results: Mean SGLs were 200 mm in group I and 277 ± 27 mm in group II. The number of segmental arteries covered was significantly different between the two groups (p < 0.001). There was no significant difference in vertebral artery dominance between groups I and II (p = 0.99). One patient in group II, who also had bilateral internal iliac artery occlusion, developed postprocedural neurological deficit referrable to SCI, which resolved completely after institution of CSF drainage. However, the incidence of SCI was not significantly different between group I and group II (p = 0.5).

Conclusion: Based on our experience, we recommend longer aortic coverage (beyond 200 mm) in type B aortic dissection (TBAD) for better aortic remodelling, provided that the mean arterial pressure of > 90 mm Hg is maintained perioperatively to avoid SCI.