Late complications after prosthetic replacement of the ascending aorta: what did we learn from routine magnetic resonance imaging follow-up?

Objective: Advances in surgical technique have improved early survival afte r surgery of the ascending aorta. However, follow-up data document serious late complications, mainly evolutive peri-prosthetic false aneurysms. Magne tic resonance imaging (MRI) has proved to be highly effective for monitorin g these complications. This study evaluates 10 years of experience with rou tine MRI for follow-up. Methods: Since January 1988, 114 patients with repl acement of the ascending aorta either for type A acute dissection (group I, 45 patients) or aneurysms (group EI, 69 patients) were followed up with an nual MRI. Prosthetic replacement was either limited to supra-coronary ascen ding aorta (45%, 51/114) or extended to the aortic root and/or the aortic a rch (55%). Biological glue was always utilized. MRI focused on periprosthet ic haematoma, analyzing signal intensity changes and volume augmentation fo r early detection of false aneurysms, and on persistent residual dissection with or without evolutive aortic aneurysm distant to the prosthesis. Resul ts: Peri-prosthetic hematomas were almost equally found in both groups (26 (58%) in group I and 42 (61%) in group II) and were detected within the fir st year. Peri-prosthetic false aneurysms developed in 15 patients (group I, seven; group II, eight) as a complication of pre-existing hematomas and we re indicated for elective reoperation. Forty-three (96%) of patients in gro up I had persistent residual dissection. Five patients in group I and two i n group II needed reoperation for evolutive aortic aneurysm. In total, 22 o f 114 (19%) patients were reoperated on during follow-up (12 (27%) in group I and ten (15%) in group II). Operative mortality was 13% (3/22). Freedom from reoperation at 1 year/5 years was: group I, 93%/84%; group II, 98%/88% . Conclusion: Peri-prosthetic haematoma occurs equally after aneurysm or di ssection repairs and is a pre-existing condition for peri-prosthetic false aneurysm; biological glue or extended repair do not prevent late complicati ons. Long-term MRI follow-up allows successful elective reoperation for lif e-threatened but asymptomatic patients. (C) 2000 Elsevier Science B.V. All rights reserved.