Frozen Elephant Trunk in Aortic Arch Disease: Different Devices for Different Pathologies

Abstract

The frozen elephant trunk technique (FET) requires the use of a pre-assembled hybrid prosthesis consisting of a standard Dacron vascular portion to replace the aortic arch and a stent graft component, which is placed into the proximal descending thoracic aorta (DTA) anterogradely in the proximal descending thoracic aorta. In Europe, two hybrid prostheses are available: the E-evita Open Plus hybrid stent graft system provided by JOTEC (Hechingen, Germany) and the ThoraflexTM Hybrid (Vascutek, Inchinnan Scotland). Recommendations for use are extensive pathologies of the arch in case of acute and chronic aortic dissection, degenerative aneurysm and intramural hematoma. The FET approach allows the replacement of the whole arch in one stage with the option of direct treatment of the proximal descending thoracic aorta based on the stent component, creating a safe landing zone for further endovascular treatment more distally. The remarkable feature of this technique is the possibility to perform more proximally (from zone 3 to zone 0) the distal anastomosis in to the arch. This allows for an easier distal anastomosis, reduced hypothermic circulatory arrest time and decreased risk of paraplegia (<5%). Early results are promising and according to the most recent series the rate of developing post-operative renal insufficiency ranges from 3 to 10%, the risk of stroke from 3% to 8% and mortality from 8–15%. The aim of the article will be to provide some knowledge about the use and application of FET procedures in different aortic situations.

Hybrid Treatment of Complex Diseases of the Aortic Arch and Descending Thoracic Aorta by Frozen Elephant Trunk Technique

“…The "proximalization" of FET fixation from zone 3 (aortic isthmus) to zone 2 (LSA) or above has been proposed by several teams in order to facilitate the distal anastomosis as well as bleeding control, to reduce the duration of lower-body MHCA, decrease segmental coverage and SCI risk, as well as prevent left laryngeal nerve injury [63][64][65]. A recent metaanalysis of 64 studies, including 7967 patients, underscored that the distal anastomosis in zone 2 was associated with a lower rate of renal failure compared with zone 3 [66].…”