Acute Type A Aortic Dissection

The patient is positioned supine and prepped and draped from the chin to the feet. The incision is a midline sternotomy, with the option of extending the incision along the left sternocleidomastoid muscle on the left, if necessary. m = muscle.

This figure demonstrates the cannulation for bypass. Either the axillary artery (A) or the femoral artery with the strongest pulse (B) can be cannulated. We favor attaching a 6 mm Dacron graft to the artery, and cannulating the graft for bypass, as shown. Bicaval venous cannulation is favored for venous return. A left ventricular vent is positioned via the right superior pulmonary vein (RSPV) and a retrograde cardioplegia cannula is positioned in the coronary sinus. a. = artery; IVC = inferior vena cava; SVC = superior vena cava.

With the patient on bypass and the left ventricle vented, cooling can begin. When the heart fibrillates, the ascending aorta can be clamped at a level proximal to the intended site of distal reconstruction. This is accomplished during the delivery of retrograde cardioplegia through the coronary sinus. Once the aorta is opened, the cardioplegia is delivered directly into the coronary ostia as demonstrated. a. = artery.

The delaminated proximal aortic layers are reapproximated between strips of Teflon felt using a continuous 3-0 monofilament horizontal mattress suture. a. = artery.

This figure depicts the reconstructed proximal aorta. The dissected layers of the aorta have been reapproximated between layers of Teflon felt. The aortic commissures are resuspended to their normal location in the aortic root with felt-reinforced sutures.

When the patient reaches the desired temperature, the period of circulatory arrest is initiated with the patient in steep Trendelenburg position. The aorta is transected at the base of the innominate artery. The delaminated layers of the distal ascending aorta are reapproximated between layers of Teflon felt with a continuous 3-0 monofilament horizontal mattress suture, in a manner analogous to that employed on the proximal ascending aorta. Note that the tourniquet surrounding the superior vena cava is tightened, and the patient is receiving continuous retrograde cerebral perfusion via the superior vena cava cannula during this portion of the procedure.

(A) The previously-chosen Dacron graft is brought to the field and anastomosed end-to-end to the reconstructed distal ascending aorta using 2-0 or 3-0 monofilament suture. (B) Once the distal anastomosis is completed, the ascending aorta and its branches are carefully de-aired by a combination of retrograde and antegrade flushing maneuvers. The graft is clamped proximal to the anastomosis, and flow is restored to the patient's head and body via the axillary artery inflow. Systemic rewarming can now be initiated.

Distal reperfusion has been initiated through a side arm of the ascending graft. This can also be accomplished by direct cannulation of the ascending graft just proximal to the distal suture line. This method would be employed if the patient had previously placed on bypass with femoral artery cannulation, or if there was some concern regarding the adequacy of perfusion via the right axillary artery. Once the distal suture line has been completed, it is critical that reperfusion be initiated in an antegrade manner.

This figure depicts the completion of the anatomic repair. The Dacron graft is shown being anastomosed to the reconstructed proximal aorta using a continuous 2-0 or 3-0 monofilament suture.

The completed procedure is depicted. The dissected ascending aorta has been removed, the valve resuspended, all air evacuated from the left circulation, and the patient has been decannulated.