Endovascular repair of acute type B aortic dissection: midterm results.

Purpose: To evaluate midterm results of endovascular stent-graft placement for acute Stanford type B dissection (TBD).

Methods: A retrospective review was conducted of 35 consecutive patients who were treated with stent-graft implantation for acute TBD between July 1996 and July 2007. Computed tomographic (CT) volumetric analysis of the true lumen (TL) and false lumen (FL) changes in 23 patients was performed, as well as evaluation of the influence of re-entry points and length of stent-graft coverage on volume changes. In addition, complications were evaluated. Follow-up was performed at 6 and 12 months and yearly thereafter.

Results: The technical success rate was 82.7%, and the 30-day mortality rate was 8.5%. Mean follow-up was 34 months. The overall survival rate at 5 years was 78.4%. Complications included retrograde type A dissections in 3 patients during the perioperative period and in 1 patient during midterm follow-up. In addition, 5 early and 3 late endoleaks were observed. Three patients were converted to open surgery and 2 needed secondary interventions. In the stented segment, stabilization of the aorta was achieved even during midterm follow-up, with a TL volume increase of 59% at 5 years and nearly stable FL volume. The segment from the distal end of the stent-graft to the celiac artery, however, showed unstable TL and FL volumes, with high standard deviations after the first postinterventional year and circumferential aneurysmal dilatation of the aorta immediately adjacent to the stent-graft in 5 patients. The abdominal aorta showed no substantial volume changes over time. The length of stent-graft coverage and the occurrence of re-entries greatly influenced FL volume changes distal to the stent-graft.

Conclusion: Serious complications can occur during and after endovascular repair of TBD. Therefore, it should be reserved for high-risk patients.