Background: To simplify extensive primary repair of the thoracic aorta in acute type A aortic dissection, we developed the open triple-branched stent graft placement technique. The early results of this new technique are reported. Methods and Results: Between June 2008 and November 2009, 30 patients with acute Stanford type A aortic dissection underwent extensive primary repair of the thoracic aorta by means of ascending aorta replacement combined with open placement of triple-branched stent graft. Placement of the triple-branched stent graft into the true lumen of the descending aorta, arch, and 3 arch vessels was technically successful in all patients. The mean cardiopulmonary bypass time, aortic cross-clamp time, and lower body arrest time were 151.8±16.69, 84.1±6.97, and 31.17±5.34 minutes, respectively. The postoperative mechanical ventilation support period and duration of intensive care unit stay were 17.93±2.35 and 62.10±9.24 hours, respectively. All implanted stent grafts were fully opened and not kinked; there was no space or blood flow surrounding the triple-branched stent graft and no sidearm graft stenosis or occlusion. The false lumen of the descending aorta distal to the stent graft closed with thrombus in 25 of 30 patients at their first postoperative scans and in 26 of 30 at the 3-month postoperative scan. Conclusions: Open triple-branched stent graft placement is an effective technique with satisfactory early results. With this technique, extensive primary repair of the thoracic aorta may become easier and safer for acute type A aortic dissection. © 2010 American Heart Association. All rights reserved.