Replacement of the Ascending Aorta With Aortic Root Remodeling Without Coronaries Reanastomosis
De Bakey and Cooley, in 1956, first replaced an ascending aneurysm with the aid of cardiopulmonary bypass. Since then, several methods evolved for the surgical repair of the aortic root and ascending aorta aneurysms. Bentall (2), in 1968, first used his technique when he noticed that it would not be possible to join the aortic wall above the coronaries to an aortic prosthesis. In 1976, Zubiate and Kay (3) closed the coronary ostia with sutures and used GSV to do an end-to-side anastomosis onto the corresponding coronary artery. In 1978, Cabrol (4) used a single 8 mm Dacron tube that functioned to supply the entire coronary circulation. In 1996, Yacoub introduced the valve-conserving technique for aortic root aneurysm or dissection (5) while Tirone David developed the technique of remodeling the aortic root and preservation of the native aortic valve (6).
The above techniques involve not only manipulations of the coronary ostia but also leaving some aortic wall around the coronary buttons. Pseudoaneurysm at the suture lines (7) and bilateral coronary ostial stenosis (8) are often seen with the classic Bentall procedures. False aneurysm formation and progression of aneurysmal disease are the predominant causes for late reoperations after aortic root or ascending aortic replacement (9). In one study, the sites of the aortic false aneurysm were either aortic suture or coronary ostium (10). In another study, reoperation for false aneurysm and the presence of coexisting coronary artery disease requiring bypass grafting were the only significant predictors of late mortality (11).
Is it always necessary to mobilize the coronaries and do four anastomoses during aortic root surgery—two for the aorta and two for the coronaries? Moreover, a growing elderly population with multiple comorbidities, technical challenges like restricted mobility of the coronary ostia, fragile tissues, as well as lack of experience preclude cardiac surgeons from doing aortic root surgery.
Leon introduced a simple technique of aortic root remodeling without handling of coronary ostia. The authors excised most of the aortic root wall except around the coronary ostia; most of the remaining aortic root wall is also reinforced by external Dacron. This ultimately remains very minimal unsupported aortic root, hence using only proximal and distal aortic anastomosis in this technique.
The authors also used a special technique for the posterior aortic wall anastomosis with five interrupted Ethibond® sutures and covered with a rectangular pericardial patch. This allows the proximal suture line to be placed close to the coronary arteries (12). The use of this technique in elderly and fragile patients avoids the risk of hidden leak and false aneurysm.
The authors have been using this technique for several years. Patients were identified during preoperative work-up for aortic valve surgery or as incidental diagnosis. They selected those patients whose ascending aorta/root were aneurysmal and came under the European Society of Cardiology guidelines. All patients had preoperative computed tomography (CT) scan, echocardiogram, and immediate preoperative and postoperative transesophageal echocardiogram (TEE) that confirmed a wrinkle-free, smooth reduction of the aortic root diameter.
The patient in this video was a 73-year-old man who presented with acute abdomen; he later underwent appendectomy. During the abdominal investigation, he had a CT scan (Figure 1) and transthoracic echocardiogram.
These tests showed that his ascending aorta and root were dilated up to 75 mm with severe aortic valve regurgitation, and his ejection fraction was 50%. His additive EuroSCORE was 11. Cumulative bypass time was 195 minutes, cumulative cross clamp-time was 142 minutes, and total circulatory arrest time was 32 minutes. He was admitted one day before the operation and was discharged on the seventh postoperative day with very good recovery.
Perioperative TEE is shown in Figure 2. Figure 3 depicts the operative field before and after the ascending aorta replacement.
Operative Steps (shown in video):
- Perform a routine median sternotomy and pericardiotomy.
- Extend the skin incision as T-shaped at the upper part of the midline skin incision. This will allow for accessing the brachiocephalic artery and left common carotid artery.
- Dissect the ascending aorta, as much as can easily be done, especially distally and in the aortopulmonary window.
- Pass the nylon tapes around the ascending aorta and brachiocephalic artery.
- Give heparin as usual.
- Select the aortic cannulation site at the distal aorta, 2 to 3 cm proximal to the level of brachiocephalic artery, at the reflection of the pericardium. Later, the cannulation site of the aorta will be excised with the aorta.
- Pass a two-stage venous cannula through the right atrium. Establish cardiopulmonary bypass as is done routinely for aortic valve surgery.
- Once again dissect and separate the ascending aorta from the surrounding tissues.
- Pass a nylon tape around the superior vena cava (SVC) and place a purse-string suture for the retrograde cerebral perfusion cannula.
- Make a purse-string suture in the right upper pulmonary vein and pass the left ventricular (LV) vent through the vein.
- Apply the aortic cross-clamp, incise and open the aorta, identify the coronary ostia, and infuse direct antegrade cardioplegia.
- Mark inside the aorta, 2 cm distal to the coronary ostia, to note the proximal aortic excision limit.
- Excise the aortic valve leaflets as routine. Excise the aorta 2 cm distal to the coronary ostia at the previously marked site.
- Place the aortic valve sutures with pledgeted Ethibond® 2-0 as routine, and repeat the cardioplegia administration through the coronary ostia.
- After repeating the cardioplegia, tie all valve sutures. Divide all of them except three, to be used as stay sutures.
- Start of aortic root remodeling.
- First step of aortic root remodeling: