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.

Combining aortic arch dissection stent implantation and root surgery for aortic dissection type A

BACKGROUND

Acute aortic dissection type A (AADA) is associated with high perioperative morbidity and mortality. A novel non-covered hybrid prosthesis (AMDS, CryoLife, Kennesaw, USA) can be easily implanted to stabilize the true lumen. However, the role of AMDS for patients requiring additional aortic root surgery has not been described.

METHODS

Between 2010 and 2020 a total of n = 370 patients underwent surgery for AADA in our department. Of those, n = 120 underwent treatment for aortic root in addition to proximal arch replacement without resection of the aorta beyond the innominate artery (Control, n = 111) and were compared to patients who received additional AMDS implantation (AMDS, n = 9).

RESULTS

Aortic valve repair was performed in 48.6% (Control) and in 55.6% of AMDS patients. Cardiopulmonary bypass (Control: 248 ± 76 min, AMDS: 313 ± 53 min, P < 0.01) time as well as circulatory arrest time of the lower body (Control: 30 ± 15 min, AMDS: 52 ± 12 min, P < 0.01) was prolonged in the AMDS group. Nevertheless, postoperative in-hospital morbidity such as dialysis (Control: 22.4%, AMDS: 11.1%, P = 0.68) and stroke (Control: 17.0%, AMDS: 22.2%, P = 0.65) were comparable. In-hospital death (Control: 21.8%, AMDS: 11.1%, P = 0.68) and the compound end-point MACCE (Control: 38.7%, AMDS: 44.4%, P = 0.74) did also not differ.

CONCLUSIONS

Addressing the arch by implantation of AMDS prolongs cardiopulmonary bypass and circulatory arrest time, however without relevant impairments of short-term outcome. Combining root surgery with replacement of the proximal aortic arch and AMDS implantation seems feasible and safe as it did not impair the early postoperative outcome.

Hemiarch Versus Arch Replacement in Acute Type A Aortic Dissection: Is the Occam's Razor Principle Applicable?

BACKGROUND AND AIM OF THE STUDY

In patients with acute Type A aortic dissection (A-AAD) whether repair should be limited to ascending aorta/hemiarch replacement or extended to include the aortic arch is still debated. We have analyzed our experience to compare outcomes of patients with A-AAD treated with these 2 different surgical strategies.

METHODS

From 2006 to 2020, a total of 213 patients have undergone repair of A-AAD at our Center; in 163 of them ascending aorta/hemiarch replacement (Group 1) and in 75 ascending aorta and arch replacement (Group 2) were performed. The primary endpoint was early survival and secondary endpoints late survival, freedom from late complications and reoperations. Patients were compared according to era of operation: 2006 to 2013 (Era 1) and 2014 to 2020 (Era 2).

RESULTS

Overall hospital mortality was 12% and 5% in Group 1 and 2; mortality remained stable in Era 1 and 2 for Group 1 (15%), while it decreased from 8% to 1% in Group 2 patients (p = 0.24). Actuarial survival at 5 and 10 years is 72 ± 4% and 49 ± 5% in Group 1 and 77 ± 6% and 66 ± 9% in Group 2 (p = 0.073). Actuarial freedom from reoperation in the entire series is 94 ± 2% and 92 ± 3% at 5 and 10 years. Freedom from reoperation at 5 and 10 years is 92 ± 2% and 89 ± 3% in Group 1 and 98 ± 1% at all intervals in Group 2 (p = 0.068).

CONCLUSIONS

An aggressive approach to A-AAD provides superior long-term results without increasing mortality. Furthermore, arch replacement during A-AAD repair represents a more stable solution with lower incidence of late aortic-related complications. Immediate aortic arch replacement should be considered in the treatment of A-AAD especially in experienced centers.

An Integrated Approach for Treatment of Acute Type A Aortic Dissection

Background and objective: We reviewed a single-institution experience to verify the impact of surgery during different time intervals on early and late results in the treatment of patients with type A acute aortic dissection (A-AAD). Materials and Methods: From 2004 to 2021, a total of 258 patients underwent repair of A-AAD; patients were equally distributed among three periods: 2004-2010 (Era 1, n = 90), 2011-2016 (Era 2, n = 87), and 2017-2021 (Era 3, n = 81). The primary end-point was to assess whether through the years changes in indications, surgical strategies and techniques and increasing experience have influenced early and late outcomes of A-AAD repair. Results: Axillary artery cannulation was almost routinely used in Eras 2 (86%) and 3 (91%) while one femoral artery was mainly cannulated in Era 1 (91%) (p < 0.01). Retrograde cerebral perfusion was predominantly used in Era 1 (60%) while antegrade cerebral perfusion was preferred in Eras 2 (94%,) and 3 (100%); (p < 0.01). There was a significant increase of arch replacement procedures from Era 1 (11%) to Eras 2 (33%) and 3 (48%) (p < 0.01). A frozen elephant trunk was mainly performed in Era 3. Hospital mortality was 13% in Era 1, 11% in Era 2, and 4% in Era 3 (p = 0.07). Actuarial survival at 3 years is 74%, in Era 1, 78% in Era 2, and 89% in Era 3 (p = 0.05). Conclusions: With increasing experience and a more aggressive approach, including total arch replacement, repair of A-AAD can be performed with low operative mortality in many patients. Patient care and treatment by a specific team organization allows a faster diagnosis and referral for surgery allowing to further improve early and late outcomes.

Do oral anticoagulants impact outcomes and false lumen patency after repair of acute type A aortic dissection?

OBJECTIVE

The study objective was to analyze the effects of chronic oral anticoagulation on long-term outcomes after repair of type A acute aortic dissection and its influence on false lumen fate.

METHODS

We studied 188 patients (median age, 62 years; 74% were male) who underwent repair of type A aortic dissection; patients receiving postoperative chronic oral anticoagulation (n = 59) were compared with those receiving antiplatelet therapy alone (n = 129).

RESULTS

Median age was similar: 60 years (18-79 years; OAC group) versus 64 years (22-86; no-OAC group) (P = .11); patients taking anticoagulants were more frequently male (88% vs 67%, P = .003). After a median follow-up of 8.4 years (2 months to 30 years), 58 patients died, 18 of aortic-related causes, and 37 patients underwent aortic reintervention. After multivariable adjustment, anticoagulation showed no significant effect on long-term survival (hazard ratio, 0.85; 95% confidence interval, 0.41-1.76; P = .66) or risk of reintervention (hazard ratio, 0.55; 95% confidence interval, 0.27-1.15; P = .11). Analysis of 127 postoperative computed tomography scans showed a patent false lumen in 53% of anticoagulated patients versus 38% of nonanticoagulated patients (P = .09): partially thrombosed in 8% versus 28% (P = .01) and thrombosed in 39% versus 34% (P = .63), respectively. In patients with a control computed tomography, there were 6 late aortic-related deaths, 1 among anticoagulated patients and 5 in those who were not.

CONCLUSIONS

Chronic anticoagulation after repair of type A acute aortic dissection favors persistent late false lumen patency, which is not a risk factor for late mortality or reoperation. Chronic anticoagulation can be administered safely to patients with repaired type A acute aortic dissection regardless of its specific indication.