Aortic Arch Replacement in Zone 2 versus 3 Using the Frozen Elephant Trunk Technique

Objectives: The frozen elephant trunk (FET) technique is used for the treatment of extensive aortic pathologies such as aortic arch and descending aortic aneurysm, as well as acute and chronic DeBakey 1 and 3 dissections. The aortic arch can be resected in either arch zone 2 or 3. We compared the in-hospital procedure-related results of both techniques.

Methods: From October 2010 to August 2019, a total of 118 patients (mean age: 61.8 ± 14.2, 57.1% males) underwent aortic arch replacement using FET for aortic dissection (n = 34 acute; n = 39 chronic) or thoracic aneurysm (n = 45). Arch replacement was performed in zone 2 (n = 54) and zone 3 (n = 64). Concomitant procedures included aortic valve replacement (n = 10), aortic root replacement (n = 30), CAB (n = 9), mitral valve reconstruction (n = 1), and tricuspid valve reconstruction (n = 2). Perioperative mortality and morbidity were compared, as well as procedure-related times, ventilation time, and ICU stay.

Results: Thirty-day mortality was 1.9% (n = 1) in zone 2 and 18.8% (n = 12) in zone 3 (p < 0.001). Morbidity included permanent cerebral neurological deficit [zone 2: n = 2 (3.7%); zone 3: n = 12 (18.8%), p = 0.004], paraparesis [zone 2: n = 1 (1.9%); zone 3: n = 3 (4.7%), p = ns], recurrent nerve palsy [zone 2: n = 1 (1.9%); zone 3: n = 13 (20.3%), p = 0.004]. Circulatory arrest (41.7 ± 10.5 vs. 67 ± 30 min; p < 0.001) and cerebral perfusion time (60.9 ± 13.5 vs. 92 ± 33 min; p < 0.001) were significantly reduced in zone 2 as compared to 3. Ventilation time (45 ± 88 vs. 79 ± 160 hours) and ICU-stay (7.3 ± 9.6 vs. 7.0 ± 7.4 days) did not show any statistical significant differences (p = ns).

Conclusion: Moving the distal anastomosis forward from arch zone 3 to zone 2 leads to a favorable neurological outcome and mortality. There is a need for further multicenter studies to establish the advantages of the FET technique in zone 2.