Optimal treatment of type B acute aortic dissection: long-term medical follow-up results

The aim of this study is to assess the long-term outcome of medical treatment and determine recent surgical indications for type B acute aortic dissection.

In the last 8 years, 79 patients were admitted to our hospital with type B acute aortic dissection. We medically treated patients at the time of onset, regardless of the aortic diameter and blood patency status in the false lumen. If the maximum diameter of dissected aorta exceeded 60 mm in any stage, early or elective surgery was performed. The mean follow-up duration was 41.2 months. We evaluated operation free rate and actuarial survival rate.

Thirteen patients underwent early or elective operations of the descending aorta. At the time of onset, the maximum aortic diameter of these patients was significantly larger than that of medically managed patients (55.8 +/- 4.4 mm vs 44.6 +/- 8.2 mm; p = 0.0004). Two patients underwent emergency axillo-femoral bypass for leg ischemia. Of the other 64 patients, who were medically managed, 2 patients had type A dissection develop during follow-up, 3 died during the initial hospital stay (1 from rupture, 1 from bronchial asthma, and 1 from gut ischemia), and 1 died of pneumonia 6 months after onset. Operation free rate was 98.6% at 1 month, 90.0% at 1 year, 78.7% at 3 years, and 69.5% at 8 years. Actuarial survival rate of medically managed patients was 98.4% at 1 month and 93.5% at 8 years.

Medical treatment of type B acute aortic dissection produced good results. Surgical intervention for type B dissection should be done when the maximum aortic diameter exceeds 60 mm.