**4. Conclusion**

*Aortic Aneurysm and Aortic Dissection*

thoracic aorta aneurysm.

10 years equal to 84.4%.

treatment of this aortic segment.

with a 3 years follow-up showed that preoperative isthmic diameter enlargement (OR = 1.11, *P* = 0.0025) and patent false lumen (OR = 13.28, *P* = 0.002) were risk factors for aneurysmal evolution [28]. Kirsch, with a longer follow-up, found a 56.1 ± 9.4% rate of reinterventions at 15 years. About 84.2% of these reinterventions were the consequence of aneurysmal evolution. After multivariate analysis, risk factors appeared to be youth, recent intervention, and type 1 dissection. Finally, the literature analysis identifies patent false lumen, preoperative isthmus diameter enlargement, preoperative descending thoracic aorta diameter enlargement over 40 mm, and long-term uncontrolled blood pressure as risk factors for descending

Performing a descending thoracic aorta treatment by hybrid approach at the initial phase, in selected patient, could be a solution for reduction of excess mortality and morbidity of this population. Thus, patients presenting a TAAD with a descending thoracic aorta diameter superior to 40 mm could benefit from a hybrid

Finally, in case of chronic dissection with aneurismal evolution reaching both

It is important to remind that this preventive treatment has to be integrated in a global management, involving medical and surgical care, including genetic screening and strict blood pressure control. Eggebrecht demonstrated that a large part of patients with aortic dissection history (40%) had resistant hypertension despite multiple drug therapy [44], especially when patients were young and obese. These results underline the necessity to refer these patients to specialists in hypertension. Furthermore, the large number of loss of view in series [19] demonstrates that TAAD is still considered merely as an acute disease. This vision is mistaken: aortic dissection is a chronic disease, beginning in an acute way, reaching the entire aorta

Visualization of the aortic flow through the streamline technique: Presence of a

The surgeon's experience is a key element of the surgical management. TAAD is a challenging pathology requiring complex surgical techniques such as aortic valve sparing and frozen elephant trunk implantation. If the operator is not familiar with aortic valve sparing repair, it is suitable to perform a Bentall intervention instead. In the same idea, performing an arch replacement followed by an endoprosthesis implantation in the descending aorta can be preferred to a frozen elephant trunk

Type B aortic dissection (TBAD) with retrograde arch extension occurs in 25%

of cases of TBAD [45]. However, even if this situation is not rare, there are no

and requiring medical and surgical long-term follow-up.

helicoidal flow downstream the endoprosthesis.

**3.3 Type B aortic dissection with arch extension**

recommendations concerning the management of this case.

• The surgeon's experience

ascending and thoracic descending aorta, two techniques can be discussed: a two-stage technique combining surgery on the ascending aorta via sternotomy and endovascular treatment of the descending aorta or a one-stage technique via bilateral thoracotomy (clamshell incision), with right subclavian and femoral perfusions and deep hypothermic circulatory arrest, allowing the replacement of the ascending, arch and descending aorta at different levels as described by Kouchoukos [43]. This last procedure provides low complications rates (mortality: 2.5%, reoperation for bleeding: 7.5%, neurological event: 2.4%) and a freedom from reoperation rate at

**98**

approach.

TAAD is a serious condition requiring emergency surgical treatment. If saving the patient remains the main objective of the surgery, long-term follow-up leads us to improve initial surgical treatment, mainly to prevent long-term aneurysmal evolution, either on the aortic root or on the descending thoracic aorta. Concerning the proximal segment, guidelines are clear: aortic root has to be replaced if the sinuses of Valsalva are involved by the dissection. Concerning the descending thoracic aorta, there is still no consensus, but studies show that hybrid surgery should be performed in case of malperfusion syndrome and when patients presents high risk factors for aneurysmal evolution.

### **Author details**

Benoit Cosset, Sarah Abdellaoui, Hugo Huvelle, Amine Fikani and Fadi Farhat\* Department of Cardiovascular Surgery B, Hospital Louis Pradel, Hospices Civils de Lyon, Université Lyon 1, Lyon, France

\*Address all correspondence to: fadi.farhat@chu-lyon.fr

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
