A 51-year-old male, who had undergone aortic valve replacement (BS27A) 13 years ago, was admitted with a sudden onset of cerebral stroke and SVC syndrome. Computed tomography and aortography revealed aneurysmal dilatation and dissection of the ascending thoracic aorta with occlusion of the superior vena cava and the right pulmonary artery. A modified Collins procedure was performed and the postoperative course was uneventful.