The Ascyrus Medical Dissection Stent: A One-Fits-All Strategy for the Treatment of Acute Type A Aortic Dissection?

The treatment of DeBakey type I aortic dissection remains a major challenge in the field of aortic surgery. To upgrade the standard of care hemiarch replacement, a novel device called an "Ascyrus Medical Dissection Stent" (AMDS) is now available. This hybrid device composed of a proximal polytetrafluoroethylene cuff and a distal non-covered nitinol stent is inserted into the aortic arch and the descending thoracic aorta during hypothermic circulatory arrest in addition to hemiarch replacement. Due to its specific design, it may result in a reduced risk for distal anastomotic new entries, the effective restoration of branch vessel malperfusion and positive aortic remodeling. In this narrative review, we provide an overview about the indications and the technical use of the AMDS. Additionally, we summarize the current available literature and discuss potential pitfalls in the application of the AMDS regarding device failure and aortic re-intervention.

Treatment of acute type A aortic dissection with the Ascyrus Medical Dissection Stent in a consecutive series of 57 cases

OBJECTIVES

The Ascyrus Medical Dissection Stent (AMDS) has been recently introduced as an alternative for total arch replacement in acute aortic dissection type A (AADA). The aim of this study was to evaluate the postoperative outcomes after AMDS treatment in a large contemporary cohort of AADA patients.

METHODS

Data acquisition was performed retrospectively at 2 German aortic centres between 2020 and 2022 and comprised the perioperative parameters and postoperative results of all AADA patients. All patients treated with the AMDS for AADA were included in the study. The primary end point was in-hospital mortality. Secondary end points were defined as early postoperative and AMDS-related complications.

RESULTS

Fifty-seven AADA patients treated by AMDS were included in the study group. The mean age was 64.6 ± 10.8 years and 59.7% (n = 34) were males. The actual in-hospital mortality was considerably lower than the predicted mortality risk by the German registry for acute aortic dissection type A score (16% vs 22%). The median ICU and in-hospital stay were 5 (interquartile range: 3-13) and 12 (interquartile range: 10-22) days, respectively. Postoperative complications comprised acute renal insufficiency (37%) with need for temporary (16%) or permanent dialysis (5%), delirium (26%), re-exploration for bleeding (14%), tracheostomy (14%) and new stroke (4%). A new AMDS-related complication (central stent collapse) was observed in 9% (n = 5) by postoperative computed tomography and chest X-ray. The incidence of complete central AMDS collapse did not impact 30-day mortality.

CONCLUSIONS

The AMDS may be successfully used in AADA with acceptable 30-day mortality in accordance with the German registry for acute aortic dissection type A score. However, careful preoperative evaluation of the patient's individual aortic anatomy regarding potential contraindications and proper device implantation are strongly recommended to avoid complete central AMDS collapse.

Initial experience with the new type A arch dissection stent: restoration of supra-aortic vessel perfusion

OBJECTIVES

The goal of the present study is to investigate changes in supra-aortic vessel perfusion after implantation of the non-covered Ascyrus Medical Dissection Stent (AMDS) for surgical treatment of acute type A aortic dissection.

METHODS

From 2017 to 2020, 16 consecutive patients treated with AMDS and involvement (dissection to total occlusion) of at least 1 supra-aortic vessel were included in the study. Centre-line based computed tomography measurements of true, false and total lumen area using Terarecon software were performed before and after surgery. Changes in the true lumen area were indexed to the entire vessel area. The paired sample t-test was used to assess the significance of the observed differences.

RESULTS

Analysis of supra-aortic vessels and the descending aorta showed significant improvement in true lumen perfusion after the AMDS was implanted. The indexed true lumen area increased postoperatively by 72%, 112% and 30% in the innominate, right and left common carotid arteries, respectively. Total occlusions of both common carotid arteries recovered completely after surgical treatment. The proximal- and the mid-descending aorta showed a 78% and 48% improvement of the indexed true lumen area, respectively.

CONCLUSIONS

Arch repair using AMDS shows promising results in the treatment of acute type A aortic dissection. Quantitative measurements of true and false lumen perfusion demonstrated a significant increase in true lumen area and a 100% regression of totally occluded supra-aortic branches. Further examination in a larger cohort of patients and comparison with isolated hemiarch repair are needed to confirm positive vascular remodelling after an AMDS implant.