**10. Technical aspects of surgical repair**

### **10.1 Aortic root management**

The aortic root is frequently involved with aortic valve rendered incompetent due to commissural dehiscence or annular dilation. Grade II and grade III aortic regurgitation was found in 40 and 23% patients, respectively, in German Registry for Acute Aortic Dissection type A (GERAADA) [36]. There are different surgical approaches for management of aortic root replacement—an aggressive or a more conservative approach.

According to the International Registry of Acute Dissection (IRAD), aortic root replacement compared with conservative root management is not associated with increased in-hospital mortality. In 1995 patients, 18 and 21.3% hospital mortality was found in root replacement and conservative root group respectively (OR 0.989; CI 0.710–1.379; p = 0.949). Mid-term results at 3 years showed a survival of 91.6+/1.3% and 92.5+/1.7% for conservative root management and root replacement group, respectively [37].

Indications to perform root replacement in a patient with ATAD include:


**71**

**Figure 9.**

*Current and Future Management Strategies of Type A Aortic Dissection*

9. aortic root as the most proximal site of dissection

of the dissected aortic root, aortic root reconstruction is done.

ii.To take the maximum possible adventitia in the anastomoses.

graft and sinotubular junction should be maintained.

cusps, as the pathology is usually limited to the aortic wall.

Proximal reconstruction technical (**Figures 9** and **10**) details: After the excision

iii.Needle should enter the tissue at right angle to avoid tearing of needle holes.

iv.Sutures should be spaced uniformly and pulled just enough tight to prevent

v.To avoid distortion of the aortic valve, the planar relationship between the

The Bentall procedure [38] is a fairly standard procedure. It includes anastomosing the composite graft to the aortic annulus and reimplantation of coronary arteries. Patients with type A aortic dissection usually have normal aortic valve

Valve sparing root replacement is a viable option in hemodynamically stable young patients. But it is technically more complex than straight aortic root replacement. It involves replacing the aortic root by composite graft without replacing the aortic valve. The native aortic root must be dissected from surrounding structures to 2 mm below the nadir of the aortic annulus. Coronary ostia are reimplanted into the graft. It is used to treat aortic regurgitation due to annular enlargement. Contraindications include significant cardiomyopathy, malperfusion, coronary

Results from Emory in a 43 patients showed operative mortality of 4.7%. Freedom from aortic valve replacement was 100% and freedom from more than mild aortic regurgitation was 94% at 9 years follow-up. No aortic root reinterventions

Conservative approaches to the aortic root (CRR)—In most of the patients presenting with TAAD, the most common pathology seen is a primary intimal tear in the ascending aorta with dissection flap extending to non-coronary cusp. Left and right coronary sinuses are relatively preserved. Any aortic regurgitation

*DOI: http://dx.doi.org/10.5772/intechopen.93015*

8. coronary artery involvement

Technical principles include:

artery disease, >65 years age.

were required in this series [39].

*Aortic root replacement (right coronary ostial anastomosis).*

i.Obliteration of false lumen.

cutting through the fragile tissue.

*Current and Future Management Strategies of Type A Aortic Dissection DOI: http://dx.doi.org/10.5772/intechopen.93015*

8. coronary artery involvement

*Advances in Complex Valvular Disease*

in left subclavian artery.

from manipulation or by jet flow [34].

decreasing the risk of embolization [35].

**10.1 Aortic root management**

conservative approach.

group, respectively [37].

2.Marfan syndrome

3.bicuspid aortic valve

4.known aortic valve disease

6.previous aortic valve replacement

5.moderate or severe aortic valve insufficiency

1.younger age

**10. Technical aspects of surgical repair**

Direct cannulation is limited by high risk of embolism due to plaque mobilisation

Axillary artery cannulation can be used to provide unilateral antegrade SCP during hypothermic arrest without manipulation of the arch vessels. This can be combined with balloon occludable perfusion catheter to left carotid artery to provide bilateral antegrade SCP. To avoid steal, an occlusive balloon catheter is inserted

Unilateral antegrade SCP is sufficient for majority of patients with no pathology of the arch vessels and cerebral vessels. Adequate backflow from the contralateral carotid artery suggests good collateralisation. Near-infrared spectroscopy (NIRS) monitoring can also help to exclude contralateral malperfusion. Bilateral cerebral perfusion may be useful in patients with carotid artery stenosis, previous stroke or cerebrovascular anomalies (incomplete Circle of Willis). Malvindi concluded in his review that "While both unilateral and bilateral ASCP are acceptable, bilateral antegrade cerebral perfu-

Cerebral perfusion is performed at a rate of 8–12 cc/min/kg body weight, perfusion

pressure of 40–60 mmHg at 23–28°C. Alpha stat pH management compared to pH stat management prevents "luxury perfusion" by marinating cerebral autoregulation

The aortic root is frequently involved with aortic valve rendered incompetent due to commissural dehiscence or annular dilation. Grade II and grade III aortic regurgitation was found in 40 and 23% patients, respectively, in German Registry for Acute Aortic Dissection type A (GERAADA) [36]. There are different surgical approaches for management of aortic root replacement—an aggressive or a more

According to the International Registry of Acute Dissection (IRAD), aortic root replacement compared with conservative root management is not associated with increased in-hospital mortality. In 1995 patients, 18 and 21.3% hospital mortality was found in root replacement and conservative root group respectively (OR 0.989; CI 0.710–1.379; p = 0.949). Mid-term results at 3 years showed a survival of 91.6+/1.3% and 92.5+/1.7% for conservative root management and root replacement

Indications to perform root replacement in a patient with ATAD include:

7.large diameter aortic annulus, sinuses of Valsalva and ascending aorta

sion is safer, when the antegrade SCP time is more than 40-50 minute" [35].

**70**

9. aortic root as the most proximal site of dissection

Proximal reconstruction technical (**Figures 9** and **10**) details: After the excision of the dissected aortic root, aortic root reconstruction is done. Technical principles include:

i.Obliteration of false lumen.


The Bentall procedure [38] is a fairly standard procedure. It includes anastomosing the composite graft to the aortic annulus and reimplantation of coronary arteries. Patients with type A aortic dissection usually have normal aortic valve cusps, as the pathology is usually limited to the aortic wall.

Valve sparing root replacement is a viable option in hemodynamically stable young patients. But it is technically more complex than straight aortic root replacement. It involves replacing the aortic root by composite graft without replacing the aortic valve. The native aortic root must be dissected from surrounding structures to 2 mm below the nadir of the aortic annulus. Coronary ostia are reimplanted into the graft. It is used to treat aortic regurgitation due to annular enlargement. Contraindications include significant cardiomyopathy, malperfusion, coronary artery disease, >65 years age.

Results from Emory in a 43 patients showed operative mortality of 4.7%. Freedom from aortic valve replacement was 100% and freedom from more than mild aortic regurgitation was 94% at 9 years follow-up. No aortic root reinterventions were required in this series [39].

Conservative approaches to the aortic root (CRR)—In most of the patients presenting with TAAD, the most common pathology seen is a primary intimal tear in the ascending aorta with dissection flap extending to non-coronary cusp. Left and right coronary sinuses are relatively preserved. Any aortic regurgitation

**Figure 9.** *Aortic root replacement (right coronary ostial anastomosis).*

**Figure 10.** *Proximal anastomoses of aortic root.*

is due to unhinging of one of the aortic valve commissural posts. The dissected sinus segments are preserved and supported with resuspension of the native valve commissural posts or prosthetic ascending aorta replacement. The advantages are that it preserves the native sinus tissue, coronary ostia are not reimplanted, shorter ischemic time, avoiding life-long anticoagulation [40]. The most commonly used methods to fortify the aortic wall include Teflon felt and biologic glue. University of Pennsylvania in their series of 489 patients showed freedom from reoperation with this technique of 96, 92 and 89% at 1, 10 and 15 years respectively. The operative mortality was 11% [41].
