20-YEAR FOLLOW-UP OF ACUTE TYPE-A DISSECTION - THE INCIDENCE AND EXTENT OF DISTAL AORTIC DISEASE USING MAGNETIC-RESONANCE-IMAGING

A persistent distal false lumen (PDFL) after surgical repair of type A aortic dissection is the most important factor in determining long-te rm survival. It has been suggested that changes in surgical technique reduce the incidence of distal false lumen. We report the findings of a 20-year follow-up (mean 5.2 years) on 87 patients who have undergone surgical repair of type A aortic dissection with all survivors underg oing magnetic resonance (MR) scanning of the entire aorta. Early morta lity was 27.5%, and actuarial 5-, 10-, and 15-year survival was 65%, 2 8% and 20% respectively. Early mortality had decreased to 18% in the l ast 5 years. The most common cause of late death was related to distal aortic disease, accounting for 47% of all late deaths with a peak inc idence at 7-10 years after surgery. The incidence of PDFL in survivors was 72%, despite the fact that 82% of all intimal tears were resected at time of operation. Incidence was not affected by extension of the repair into the aortic arch nor by the use of the open technique or Ge latin-Resorcine-Formal tissue glue. In patients with a distal false lu men 6% had reached a maximum aortic diameter of 6 cm in at least one p lane on MR scanning and 25% had reached 5 cm. We conclude that if diss ection has extended beyond the arch at time of presentation then the c hoice of surgical technique does not prevent the persistance of a dist al false lumen. MR scanning gives ideal anatomical and functional asse ssment of distal aortic disease and provides the surgeon with all the necessary information to plan the timing and indications for further s urgery.