The aim was to evaluate long-term outcomes after surgical treatment of acute type A dissection. Between 1993 and 2004, 199 consecutive patients were operated on for acute type A dissection. All survivors were included in an MRI follow-up program. Follow-up time averaged 4.45 years. Overall survival was 96%, 80% and 65% at 1, 5 and 10 years. The false lumen remained patent in 101 cases (69%). Predictive factors for thrombosis of the false lumen were age >70 years old and valve-sparing aortic root reconstruction. Significant risk factors for patency of the distal false lumen were age <50 years old, De Bakey type III retrograde dissections, Bentall procedure and long-term anticoagulation. Freedom from reoperation was 98%, 96% and 69% at 1, 5 and 10 years. Eight patients required reoperations for dilatation of distal aorta at 4.7+/-2.8 years after the first operation. Reoperations consisted of combined surgical and endovascular procedures, without in-hospital or late deaths. Close MRI follow-up demonstrated that aortic false lumen remained patent in a majority of cases. Surgical reconstruction needing long-term anticoagulation must be avoided when possible to decrease patency of the false lumen. However, late reoperations are infrequent and can be treated with a low risk by using endovascular procedures.