Fig. 7.5. Repair of Type A aortic dissection with valve resuspension. (a) Type A aortic dissection with aortic insufficiency. Right atrial-femoral artery bypass is established. (b) Longitudinal aortomy revealing true and false lumens. (c) Resuspension of aortic valve with two plegetted sutures at each commissure. (d) Inner and outer felt secured at proximal and distal aorta using a whip stitch. (e) Interposition tube graft placed between proximal and distal aorta.

Fig. 7.6. Bentall procedure.

(a) Right atrial-femoral bypass and cardiac arrest are used. A longitudinal aortomy performed and the appropriate sized valved conduit chosen.

(b) The valve is seated. Coronary orifice holes are made in the tube graft with an ophthalmic electrocautery. (c) Anastomosis of the left main coronary artery to the graft. Felt has been placed to reinforce the coronary os-tium. (d) Completed left main coronary anastomosis. The right coronary followed by distal anastomosis will be performed next.

Type B dissections. These patients generally do not require surgery unless their pain is not controlled after an appropriate course of antihypertensive management or if they have visceral sequelae of their dissection. This includes decreased blood flow to the renal arteries, celiac axis, superior mesenteric artery, or shearing off of the artery of Adamkiewitz with spinal ischemia or limb threat from shearing off of the iliac vessels.

Critical aspects in determining the surgical management of acute aortic dissection include whether or not there is coronary artery involvement, aortic insufficiency, and the presence of an intimal tear in the transverse arch (Table 7.2). Half of patients with Type A dissections have aortic insufficiency which must be taken care of by resuspension (Fig. 7.5a-e) or aortic valve replacement. Aortic valve replacement for aortic dissection must be done as a Bentall or Cabrol procedure, or separate aortic valve and ascending graft replacements must be done.

A Bentall procedure (Fig. 7.6a-d) is a composite aortic valve replacement with replacement of the ascending aorta and re-implantation of the coronary artery orifices directly into the graft. The Cabrol is a simplified procedure in which the coronary orifices are not re-implanted directly into the graft, but rather a separate 8 mm Dacron graft is sewn onto both coronary orifices and then attached to the ascending aortic graft (Fig. 7.7a-b). This is technically easier than is separate reimplantation of the coronary orifices into the graft. Alternatively, a separate aortic valve replacement and ascending graft replacement can be done and the coronary

Cabrol Procedure
Fig. 7.7. Cabrol procedure. (a) The aortic valve has been excised and the valved conduit seated in position. An 8 mm Dacron graft is used to anastomose the right and left coronary orifice to the valved conduit. (b) The distal aortic anastomosis is performed next.

orifices left alone without reimplanting them. If the coronary arteries are spared from the dissection, they need not be reimplanted into the graft. If they are involved, a Bentall or Cabrol procedure is required.

Where does one attach the graft distally? The dissection may continue around the aortic arch and even down into the descending thoracic aorta as with type I dissections. However, one does not need to go to the distal most extent of the dissection; one simply needs to eliminate the intimal tear. One can plicate the distal true and false lumens with felt and then attach this to the graft, thus obliterating the false lumen distally. For descending thoracic dissections, as for ascending, one can leave the dissection false lumen distally and simply plicate the true and false lumen distal to the intimal tear.

Technique for Repair of Ascending and Transverse Arch Dissections For acute aortic dissection involving the ascending aorta or transverse arch, right atrial-femoral artery bypass is established. During the process of actively cooling, a cross-clamp is applied to the aorta proximal to the innominate artery. The aortic root is opened and cardioplegia solution administered retrogradely or directly into the coronary orifices. At this point, a decision regarding the transverse arch must be made. If there is an obvious intimal tear in the ascending aorta and there is no real suspicion of a transverse arch intimal defect, then profound hypothermia and circulatory arrest is not required. Replacement of the ascending aorta and, if necessary, valve replacement or resuspension and coronary reimplantation can be performed. If, however, there is suspicion of transverse arch involvement, or if an intimal tear in the ascending aorta is not evident, or if the tear is too close to the aortic cross-clamp to permit an adequate sewing margin, then the patient must be cooled to 18°C in anticipation of circulatory arrest. While cooling is underway, aortic valve resuspension or replacement is performed if necessary, and if coronaries must be reimplanted this is performed as well. With the patient cooled to 18°C, circulatory arrest is established. The patient is placed in Trendelenburg to prevent air from entering the cerebral vessels, and the cross-clamp is released. The arch is inspected and intimal tears are managed as direct in

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