**13. Frozen elephant trunk (FET)**

The immediate post-operative results have improved post type A Aortic dissection repair. However, long-term results are guarded by the need for aortic re-interventions due to residual dissection and patent false lumen extending into descending thoracic aorta [46]. The frozen elephant trunk technique involves total arch replacement and per-procedural deployment of stent through the true aortic lumen. It is more complex and takes more time. However, there is 90% chance of false lumen obliteration and reduced rates of re-intervention and improved longterm survival [47]. Uchida et al. [47] showed improved survival in the FET group at 5 years (95.3% vs. 69%, p = 0.03) and 100% thrombosis of false lumen in FET group compared to 29% patent false lumen in the non-FET group. However, both groups had similar operative mortality. Caution should be exercised that it should be done in high volume centres and by experienced suregons.as the total duration of hypothermic circulatory arrest can be dramatically increased.
