[Two case reports of Stanford type A acute aortic dissection complicated with thrombosed false lumen and saccular aneurysm formation].

We report two cases of successful surgical treatment for Stanford type A aortic dissection with thrombosed false lumen and saccular aneurysm formation. They were admitted to our clinic for severe anterior chest and back pain. Diagnosis was made as a Stanford type A dissection with thrombosed false lumen by chest CT, aortography and cardiac ultrasonography. Aortography showed ulcer like projection (ulp) in the ascending aorta, although flow in false lumen was not visualized. They were initially treated with antihypertensive drugs. Six and eight weeks later, although medical therapy was continued, a saccular aneurysm of the ascending aorta was found to be increased in size rapidly in both cases. Operation performed was the ascending aorta replacement with resection of the saccular aneurysm. The location of the ulp was found to be corresponded with the intimal tear at surgery. The postoperative courses were uneventful. Thus, careful medical follow up and surgical treatment were necessary in these cases. We believe that the ulp represents defect in the intima leading to the clotted false lumen and provides a possible sign of rupture in clinical course of aortic dissection.