Midterm results with thoracic endovascular aortic repair for chronic type B aortic dissection with associated aneurysm.

OBJECTIVE Thoracic endovascular aortic repair for chronic type B aortic dissection with associated descending thoracic aneurysm remains controversial. Concerns include potential ischemic complications due to branch vessel origin from the chronic false lumen and continued retrograde false lumen/aneurysm sac pressurization via fenestrations distal to implanted endografts. The present study examines midterm results with thoracic endovascular aortic repair for chronic (>2 weeks) type B aortic dissection with associated aneurysm to better understand the potential role of thoracic endovascular aortic repair for this condition. METHODS Between March 2005 and December 2009, 51 thoracic endovascular aortic repair procedures were performed at a single institution for management of chronic type B dissection. The indication for thoracic endovascular aortic repair was aneurysm in all cases. A subset of 7 patients (14%) underwent placement of the EndoSure wireless pressure measurement system (CardioMEMS, Inc, Atlanta, Ga) in the false lumen adjacent to the primary tear for monitoring aneurysm sac/false lumen pulse pressure after thoracic endovascular aortic repair. RESULTS Mean patient age was 57±12 years (range, 30-82 years); 14 patients (28%) were female. Mean aortic diameter was 6.2±1.4 cm. There were no in-hospital/30-day deaths, strokes, or permanent paraplegia/paresis. There were no complications related to compromise of downstream branch vessels arising from the false lumen. Two patients (3.9%) who had preexisting ascending aortic dilation had retrograde acute type A aortic dissection; both were repaired successfully. Median postoperative length of stay was 4 days. Mean follow-up is 27.0±16.5 months (range, 2-60 months). Actuarial overall survival is 77.7% at 60 months with an actuarial aorta-specific survival of 98% over this same time period. Actuarial freedom from reintervention is 77.3% at 60 months. All patients with the EndoSure wireless pressure measurement system exhibited a decrease in aneurysm sac/false lumen pulse pressure indicating a depressurized false lumen. The aneurysm sac/false lumen pulse pressure ratio decreased from 52%±27% at the predischarge measurement to 14%±5% at the latest follow-up reading (P=.029). CONCLUSIONS Thoracic endovascular aortic repair for chronic type B dissection with associated aneurysm is safe and effective at midterm follow-up. Aneurysm sac/false lumen pulse pressure measurements demonstrate a significant reduction in false lumen endotension, thus ruling out clinically significant persistent retrograde false lumen perfusion and provide proof of concept for a thoracic endovascular aortic repair-based approach. Longer-term follow-up is needed to determine the durability of thoracic endovascular aortic repair for this aortic pathology.