From Zone -1 to Zone 3: Feasibility and Safety of Complex Endovascular Aortic Repairs in Type A Aortic Dissection

Objective: Over 30% of patients presenting with acute type A aortic dissection (ATAAD) are considered high - risk or inoperable. This study aims to investigate the early and mid-term outcomes of complex endovascular aortic repair of aortic root, ascending aorta, and aortic arch among patients with ATAAD.

Methods: From January 2018 to January 2023, 29 patients who were considered high risk for open operation underwent endovascular aortic repair. Patients were considered high risk due to: frailty (N=14), severe malperfusion (N=5), chronic obstructive pulmonary disease on home oxygen (N=4), frozen chest (N=3), metastatic cancer (N=3), ejection fraction < 20% (N=4), and cirrhosis (N=2). For an isolated tear in the ascending aorta (Zone 0), ascending stent graft placement was performed using commercially available aortic stent grafts. For patients with a tear in the aortic root, Endo-Bentall was performed using a physician-modified modular device composed of a self-expanding transcatheter aortic valve incorporated inside an aortic stent graft. For patients with a tear in the ascending aorta as well as the aortic arch (Zone 0, Zone 1, 2), ascending stent graft placement and endovascular arch repair was performed. Follow-up electrocardiogram-gated computed tomography (CT) was performed to evaluate aortic remodeling.

Results: The mean age for this cohort was 76.3 ± 11.1 years. Endovascular repairs included: Isolated ascending stent placement in 65.5% (19/29), Endo-Bentall in 6.9% (2/29), Endo-Bentall plus Endo arch in 6.9% (2/29), and ascending TEVAR + Endo arch in 20.7% (6/29). The operative mortality was 10.3% (3/29). Stroke rate was 10.3% (3/29). During the follow-up time of a median of 6.25 months (range 0.85 to 64.6), an endoleak was observed in 42.3% (11/26) patients (80% among patients with a tear < 2cm of STJ). Seven patients had a type 1a endoleak, while four patients had a type 1b endoleak on follow-up CTA. Three patients required reintervention. The Kaplan-Meier 5-year probability of survival for the entire cohort post-intervention was 35%.

Conclusion: Early outcomes of complex endovascular repair of ascending aortic dissection are promising with acceptable mortality and stroke rate. However, the rate of endoleak after isolated ascending TEVAR with a tear within 2cm of the aortic root is high with poor long-term survival.