Division of Cardiovascular Surgery, Hiroshima-city Asa General Hospital, 2-1-1, Kabe-minami, Asa-Kita-Ku, Hiroshima 731-0293, Japan *Corresponding author. Tel.: +81-82-815-5211; fax: +81-82-814-1791. E-mail address : uchidacvs{at}yahoo.co.jp (N. Uchida). This study is retrospectively to evaluate strategies for organ malperfusion on the view point of two mechanisms (true lumen collapse in the aorta=Ao type, or branch dissection=Br type) in acute type B aortic dissection. There were 16 of Ao type and 4 of Br type in 20 patients with organ malperfusion. In Ao type, we performed entry closure in 12 patients, surgical bypass grafting in two to superior mesenteric artery (SMA) in one and femoral artery in two, and surgical fenestration in two. In Br type, we performed interventional non-covered stenting to the orifice of visceral arteries in two patients, surgical bypass to SMA with ileum resection in one, and surgical bypass to SAM and renal arteries in one. Five patients in 16 of Ao type died within 30 days that had two multiple organ failure after entry closure, one aortic injury during endovascular stent graft repair, two more multiple organ failure after femoral bypass, however, all four patients in Br type were rescued. Central aortic operation to true lumen collapse with entry closure for Ao type ischemia and organ reperfusion with extra-anatomical bypass or non-covered stent to ischemic arteries for Br type ischemia should be performed before catastrophic status. Key Words: Acute aortic dissection; Organ malperfusion; Surgical strategies