SIGNIFICANCE OF DISTAL FALSE LUMEN AFTER TYPE-A DISSECTION REPAIR

Fifty-eight patients underwent repair of acute type A dissection betwe en 1986 and 1992. Follow-up aortogram, computed tomographic scan with contrast, magnetic resonance imaging scan, or a combination of these t ests was available in 38 patients with preoperatively patent distal fa lse lumens. All distal anastomoses were constructed with the open tech nique during a period of circulatory arrest. There were 25 suture and 13 intraluminal graft anastomoses. Patency of the distal false lumen w as found in 47.3%. Use of the intraluminal graft for the distal anasto mosis decreased patency, although not significantly (4/13, 30% versus 14/25, 56%; p = 0.14). The direction of flow into the false lumen was antegrade in 11 of 24 (45.8%) of sutured anastomoses and 0 of 9 intral uminal graft anastomoses (p < 0.01). Actuarial survival at 5 years for patients with closed distal false lumen was 95% +/- 4.8% versus 76% /- 15% for patients with patency of the distal false lumen (p = not si gnificant). Event-free survival at 5 years for both groups was 84% +/- 8.3% (closed false lumen) and 63% +/- 13.5% (patency of distal false lumen; p = not significant). This experience indicates that in the tre atment of acute type A dissections, operative strategy and anastomotic technique play a role in reducing the incidence of patency and relate d complications of the distal false lumen.