The risk of spinal cord injury during the frozen elephant trunk procedure in acute aortic dissection

Abstract

OBJECTIVES The aim of the study was to access the extended occlusion of the intercostal arteries by a stent graft in the development of postoperative spinal cord injury during aortic arch surgery using the frozen elephant trunk technique. METHODS A total of 37 consecutive patients underwent total aortic arch surgery using the frozen elephant trunk technique between March 2012 and July 2017. The mean age of the patients was 54.7 ± 10.5 years. Type A and Type B aortic dissections were the indications for surgery. Moderate hypothermia and antegrade cerebral perfusion via the innominate artery were utilized. The mean diameter of the implanted stent graft was 27.7 ± 2 mm (range 24-30 mm). RESULTS No permanent spinal cord injuries occurred. The distal edge of the stent graft was in the T7-T12 range. Its lower edge was implanted at the T9-T12 level in 25 (67.6%) cases. Preoperatively, the mean number of intercostal arteries was 10 ± 1 on the left side and 10 ± 2 on the right side (P = 0.59). Postoperatively, the mean number of open segmental arteries was 3 ± 2 on the left and 4 ± 1 on the right (P = 0.003). CONCLUSIONS The frozen elephant trunk procedure is associated with the occlusion of most (two-thirds) of the intercostal arteries. Maintenance of adequate blood flow in the subclavian and iliac arteries is an integral prerequisite for a favourable outcome. The level of the deployment of the distal edge of the stent graft does not play a defining role.