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

Abstract

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.

FIGURE 1

Mid-sagittal CT angiogram images of (A) thoracic aorta with chronic type B dissection with aneurysmal dilatation of the false lumen of the chronically dissected aorta and (B) after TEVAR with false lumen EndoSure (CardioMEMS, Inc, Atlanta, Ga) aneurysm sac/false lumen pulse pressure sensor in place. True lumen is reestablished with thrombosed false lumen and aneurysm sac/false lumen pulse pressure device. C, Three-dimensional reconstruction of B.

FIGURE 2

CT angiogram demonstrating acute type A aortic dissection 5 days after TEVAR for a chronic type B dissection with associated aneurysm. Note Zenith TX2 stent graft in descending thoracic aorta with completely thrombosed descending false lumen/aneurysm sac and new dissection flap in dilated ascending aorta.

FIGURE 3

Actuarial (Kaplan–Meier) overall (solid line) and aorta-specific (dotted line) survival at 60 months post-endovascular repair for chronic dissection with aneurysm. Overall survival is 77.7% and aorta-specific survival is 98% at 60 months.

FIGURE 4

Preoperative (A) and 2-year post-TEVAR follow-up (B) 3-dimensional CT angiograms of a chronic type B dissection with associated aneurysm. Note large aneurysm with chronic false lumen in (A) with complete reverse remodeling of entire thoracic aorta in (B) such that no residual aneurysm/ dissection remains in the thoracic aorta.

FIGURE 5

Actuarial (Kaplan–Meier) freedom from reintervention is 80% at 12 months and 77.3% at 60 months post-endovascular repair.