Acute and Midterm Results after AMDS (Ascyrus Medical Dissection Stent) Implantation for Arch Remodeling in the Treatment of Acute DeBakey-I Dissections: A Prospective International Trial

Objectives: Follow-up computer tomography (CT) data show that the persistence of the intimal flap at the distal aortic anastomosis leads to creation of Distal Anastomotic New Entry (DANE) in 72% of patients, leading to false lumen (FL) pressurization besides true lumen (TL) collapse and to increased mortality, untreated malperfusion, aortic growth, and reinterventions. The AMDS reduces the pressure and the perfusion in the FL at the distal anastomosis, while expanding and pressurizing the TL. We present acute and midterm outcomes after the adoption of this treatment.

Methods: The DARTS Trial is a prospective, nonrandomized international study. Patients that underwent surgery for acute DeBakey-I aortic dissections were enrolled between March 2017 and January 2019. Follow-up control examinations are scheduled at 1, 3, 6, and 12 months postoperatively and then annually through 5 years.

Results: Forty-seven patients were enrolled (age 63.0 ± 11 years). All patients received surgical aortic repair with AMDS implantation. In 55.3% (26/47) of patients preoperative malperfusion was present. The median follow-up was 357 days. The average implantation time for the AMDS was 3.0 minutes. Sealing of the FL at the distal anastomosis was achieved in 93.6% (44/47). Overall mortality at 30 days and 1 year was 12.8% (6/47) and 19.1% (9/47), respectively, while new strokes occurred in 6.4% (3/47). No distal aorta related deaths, nor any device related adverse events were observed. AMDS induced TL expansion led to an overall 95.5% resolution of vessel malperfusion, including three patients presenting preoperative paralysis that showed full postoperative recovery. Postoperative spinal cord ischemia was 0%. No aortic arch reinterventions were needed, whereas a secondary endovascular intervention was performed in four patients. Every patient showed positive remodeling of the aortic arch, with complete obliteration or thrombosis of the FL in 76.3%. In the proximal descending thoracic aorta, positive remodeling, and stabilization was observed in 89.5% and complete or partial FL thrombosis occurred in 44.7% of cases.

Conclusion: Sealing the distal anastomotic tear through the AMDS-implantation reduces the FL perfusion, promotes TL expansion, and the resolution of malperfusion. This single-stage aortic arch repair technique induces positive remodeling of the aortic arch, without an increase of technical complexity, operative time, or surgical risk. The AMDS implantation is safe and reproducible in adjunct to the current standard-of-care surgical therapy.