OBJECTIVES: This study investigates early and midterm outcomes after surgery for acute DeBakey type I dissection between classic hemiarch replacement or additional open noncovered stenting of the aortic arch. METHODS: Patients who underwent surgery for acute DeBakey type I dissection receiving solely hemiarch replacement (2015-2022) or additional open noncovered stenting of the aortic arch (2018-2022) using the "Ascyrus Medical Dissection Stent" (AMDS) were included. After propensity score matching, the groups were compared in terms of clinical and radiological outcomes. RESULTS: A total of 261 patients (155 hemiarch, 106 AMDS) were included. After matching, the cohort comprised two balanced groups with 108 patients (54 each group): thirty-day mortality was 19% in the hemiarch group vs 15% in the AMDS group (p = 0.61, OR = 0.77 (CI 0.27-2.12)). New postoperative stroke (p = 0.99, OR = 0.98 (CI 0.11-8.43)) and revision for malperfusion did not differ (p = 0.38, OR = 1.70 (CI 0.53-5.99)). The incidence of new distal anastomotic entries was significantly lower in the AMDS group with 17% vs 45% in the hemiarch group (p = 0.028, OR = 0.35 (CI 0.13-0.87)). True lumen expansion was significantly improved in the aortic arch (p = 0.006, OR = 3.15 (CI 1.41-7.34)) and stented portion of the descending aorta (p <
0.001, OR = 8.51 (CI 3.65-21.24)) as well as false lumen thrombosis in the aortic arch (p = 0.048, OR = 2.24 (CI 1.02-5.07)). Two-year survival did not differ (p = 0.170). CONCLUSIONS: Additional AMDS implantation shows similar clinical outcomes, reduces the risk for new distal anastomotic entries and may be associated with superior positive aortic remodelling in the aortic arch and stented portion of the descending aorta. Long-term results regarding aortic remodelling and reintervention rate are highly needed.