LAS VEGAS (FRONTLINE MEDICAL NEWS) – Patients with acute, complicated type B aortic dissections are reported to have a greater than 50% likelihood of dying from their condition. Three-year results of the Valiant thoracic stent graft in the treatment of these dissections showed freedom from all-cause mortality of 79.4%, and a freedom from dissection-related mortality of 90%, according to Ali Azizzadeh, MD .

Dr. Azizzadeh presented the midterm results of the Medtronic Dissection US IDE trial of endovascular treatment with the Valiant Captivia thoracic stent graft (Medtronic) in acute, complicated type B aortic dissection patients at the 2016 Vascular Interventional Advances meeting.

One-year outcomes of the trial were reported last year in the Annals of Thoracic Surgery ( 2015 Sep;100:802-9 ).

Dr. Azizzadeh is a vascular surgeon at the Memorial Hermann Heart and Vascular Institute, Houston.

Between June 2010 and May 2012, 50 patients with acute, complicated type B aortic dissection were enrolled at 16 clinical sites in the United States in this multicenter, prospective, nonrandomized trial with a planned 5-year follow-up.

The primary safety endpoint was all-cause mortality within 30 days from the index procedure.

A total of 28 patients completed their 3-year follow-up. Through 3 years, there were no postindex ruptures or conversions to open surgical repair reported in the trial.

At 3 years, true lumen diameter over the stented region (or endograft segment) remained stable or increased in 92.3% of patients, according to Dr. Azizzadeh. False lumen diameter remained stable or decreased in 69.3% of patients, and the false lumen was partially or completely thrombosed in 75% of patients.

One death (from sepsis) occurred between years 2 and 3; and was adjudicated by the clinical events committee as unrelated to the device, the procedure, or the dissection.

Although these midterm results are encouraging, said Dr. Azizzadeh, longer-term outcomes are needed to assess the durability of the stent graft in this indication.

The trial was sponsored by Medtronic. Dr. Azizzadeh has consulted for and received research/trial funding from W.L. Gore & Associates and Medtronic.