Evolution of aortic dissection after surgical repair

Patients after aortic dissection repair still have long-term unfavorable pr ognosis and need careful monitoring. The purpose of this study was to analy ze the evolution of aortic dissection after surgical repair in correlation to anatomic changes emerging from systematic magnetic resonance imaging (MR I) follow-up. Between January 1992 and June 1998, 70 patients underwent sur gery for type A aortic dissection. Fifty-eight patients were discharged fro m the hospital (17% operative mortality) and were followed by serial MRI fo r 12 to 90 months after surgery. In all, 436 postoperative MRI examinations were analyzed. In 13 patients (22.5%) no residual intimal flap was identif ied, whereas 45 patients (77.5%) presented with distal dissection, with a p artial thrombosis of the false lumen in 24. The yearly aortic growth rate w as maximum in the descending aortic segment (0.37 +/- 0.43 cm) and was sign ificantly higher in the absence of thrombus in the false lumen (0.56 +/- 0. 57 cm) (p <0.05). There were 4 sudden deaths, with documented aortic ruptur e in 2. Sixteen patients underwent reoperation for expanding aortic diamete r. In all but 1 patient, a residual dissection was present (in 13 without a ny thrombosis of the false lumen). Close MRI follow-vp in patients after di ssection surgical repair can identify the progression of aortic pathology, providing effective prevention of aortic rupture and timely reoperation. Th rombosis of the false lumen appears to be a protective factor against aorti c dilation. (C) 2000 by Excerpta Medica, Inc.