Material and Method: Between January 2005 and September 2010, 48 consecutive patients with aortic dissection were followed with computed tomographic angiography (CTA), including 18 post-surgical repaired type A patients and 30 type B (14 conservative treatment and 16 post stent-grafting therapy). CTA were performed with a mean of 5.2 scans per patient, and a mean follow-up of 37.08 months. The diameter of the aorta, true lumen, and false lumen were measured by axial scan images and multi-planar reformatting (MPR).

Results: In medically managed patients with type B aortic dissection, the aortic diameter increased over time at mean rate 1.49 mm/year at proximal descending aorta with greater increased in size of the false lumen diameters than the true lumen diameter. In post-surgical repaired type A and post stent-grafting therapy type B aortic dissection, aortic diameter did not change over time. In addition, 12 of 16 patients (75%) patients with post stent-grafting therapy type B dissection had partial thrombosed in false lumen and 4 of 16 patients (25%) had complete resolution of false lumen.

Conclusion: In post-surgical repaired type A and post stent-grafting therapy type B aortic dissection, aortic diameter did not change over time. Type B aortic dissection with medical treatment had minimal increased in aortic diameter over time. The results suggested that uncomplicated type B aortic dissection requires on-going medical treatment.

Keywords: Aortic dissection, Stent-graft, True lumen, False lumen, Medical treatment, Aortic diameter