Aortic Wall Enhancement Detected by Contrast Enhanced CT Scan Predicts Aortic Remodeling After Optimal Medical Treatment. “A New Prognostic Predictor for Acute Uncomplicated Type B Dissection”

Abstract

Introduction - The INSTEAD XL trial showed that thoracic endovascular aneurysm repair (TEVAR) for uncomplicated type B dissection (uTBD) in the subacute phase promotes aortic remodeling and avoids aortic related death five years after onset. However, there are some patients who have undergone complete aortic remodeling with optimal medical treatment (CR) and have experienced severe complications after TEVAR, such as retrograde type A dissection. Therefore, who should undergo elective TEVAR and when it should be performed are unknown. We reported that aortic wall enhancement (AWE) after endovascular aneurysm repair for abdominal aortic aneurysm was a good prognostic predictor. However, there have been no reports focusing on the relationship between AWE and aortic dissection. We evaluated the relationship between AWE and acute uTBD. Methods - From March 2012 to February 2017, data on 44 patients diagnosed acute uTBD in our hospital were retrospectively collected. AWE was defined as an increase of more than 20 Hounsfield units in mean computed tomography values comparing images in delayed contrast enhanced scans with those in plain scans evaluated within one month from onset. Traumatic dissection, type A dissection, complicated type B dissection, chronic dissection, and within twenty weeks of follow up after onset were excluded. The primary endpoint was CR by latest contrast enhanced computed tomography scan. Results - There were 34 males (77.3%), and median age was 67.5 years (48 - 88). The median follow-up period from onset was 94.6 weeks (22 - 280). There were 26 cases (59.1%) with AWE. Twenty patients underwent surgery 2 weeks from onset, and there was no significant difference between with and without AWE (34.6% vs. 61.1%, p=0.083). CR was observed in 15 patients, and there was a significant difference between with and without AWE (50.0% vs. 11.1%, p=0.007). Conclusion - AWE was associated with CR for acute uTBD. This new prognostic predictor may play an important role in judging whether elective TEVAR is warranted.