Frozen Elephant Trunk versus Ascyrus Medical Dissection Stent in Acute Type A Aortic Dissection: Choosing the Appropriate Arch Strategy.

Abstract: Optimal management of the aortic arch during repair of acute type A aortic dissection remains debated. Hemiarch repair can achieve acceptable early survival, but persistent false lumen perfusion and residual distal dissection may contribute to later distal aortic enlargement or reintervention in a subset of patients. The frozen elephant trunk (FET) technique aims to improve distal aortic remodeling by covering intimal tears, expanding the true lumen, and promoting false lumen thrombosis, but it adds operative complexity because it requires more extensive arch reconstruction and supra-aortic vessel management. The Ascyrus Medical Dissection Stent (AMDS), an uncovered nitinol stent, has emerged as an adjunct to hemiarch repair. It is intended to reduce distal anastomotic new entry tears, support true lumen expansion, and facilitate distal aortic stabilization without formal total arch replacement. Contemporary evidence from the DARTS and PERSEVERE studies and observational series suggests that FET and AMDS may serve different operative goals in selected patients, although their roles are overlapping rather than mutually exclusive. FET may be more suitable when more extensive distal arch or proximal descending aortic pathology is present, whereas AMDS may be considered when a less extensive arch procedure is desired in the setting of arch instability or malperfusion. Neither approach should be viewed as universally superior. Instead, strategy should be individualized on the basis of patient age, intimal tear location, malperfusion status, operative risk, and institutional experience. AMDS may represent an additional option in selected high-risk patients.