Stented elephant trunk procedure combined with ascending aorta and arch replacement for acute type A aortic dissection.

Abstract
Objectives: Despite steadily improving outcomes, surgery for acute type A aortic dissection has several unresolved problems such as expansion of the residual false lumen in the descending aorta. We performed transaortic stented graft implantation into the descending aorta combined with the ascending aorta and aortic arch replacement for acute type A aortic dissection. We review the efficacy and outcomes of this procedure with respect to the residual false lumen and postoperative neurologic complications we encountered. Methods: Nine consecutive patients with acute type A aortic dissection underwent this procedure. The stented elephant trunk graft was implanted through the aortic arch under hypothermic circulatory arrest. The stented graft was 15 cm long in six patients, and 10 cm long in three patients. Enhanced computed tomography (CT) was performed 1 month after surgery and once each year after discharge to evaluate the postoperative time course of the residual false lumen. Results: Cardiopulmonary bypass (CPB) time was quite long because of slow cooling and re-warming [352±92 (mean±SD) min], and average lower-body arrest time was 54±10 min. The intima in one patient was injured at the time of implantation, and a small leak was created. One patient died of multiorgan failure postoperatively. One patient suffered cerebral injury, and two suffered spinal cord injury perioperatively. Average follow-up time was 40.4 months (range, 13–66 months). One patient died of cerebral infarction during follow up, and the other seven survived and remain well. Postoperative enhanced CT scans showed that the dissected descending aortas attached to the stented grafts and the aortas near the stented grafts returned to normal. In one patient with no re-entry, the false lumen completely closed with thrombi and the entire aorta returned to normal. The diameter of the descending aorta decreased or did not change in six of the seven patients (85.8%) and increased by only 2 mm in one of them (14.2%) during follow up. Conclusions: Implantation of a stented elephant trunk into the descending aorta combined with replacement of the ascending aorta and total arch for acute type A aortic dissection is effective in closing the residual false lumen of the descending aorta and in preventing expansion of the descending aorta. However, further technical modifications, such as using a short stented elephant trunk, eliminating aortic clamping, shortening CPB and spinal cord ischemic time, and reconstruction of left subclavian artery, are needed to prevent neurologic complications.