Operative Technique
All patients underwent median sternotomy for access. Cannulation strategies varied: venous cannulation of the right atrium was usually attempted. Arterial cannulation usually involved the femoral or right axillary artery cannulation. For the latter, a tube graft was usually anastomosed to the target vessel in order to receive the cannula. Myocardial protection was achieved with cold-blood cardioplegia solution, infused retrogradely via the coronary sinus or antegrade directly through the coronary ostia. A left ventricular vent was commonly inserted via the right superior pulmonary vein. Hypothermic circulatory arrest was used in most cases, and the arch was inspected for tears.
The goal of surgery was to resect the intimal tear, replace the ascending aorta with a prosthetic graft, and restore the anatomy of the aortic root. This study included patients in whom the aortic root or valve was deemed to be diseased beyond repair, necessitating ARR. The majority of patients requiring ARR with biological substitutes received a Freestyle graft, compared to patients selected for mechanical prosthesis who underwent ARR with a mechanical CVG. Patients receiving a bioprosthetic CVG, although few, were not excluded.
Following excision of the native aortic root and sizing of the annulus, the graft (either PAR or CVG) was sewn into the aortic annulus with interrupted sutures. The method for reimplantation of the left coronary button on the Freestyle prosthesis was left to the discretion of the surgeon, either to the left or right coronary stump of the graft (the remaining stump is usually oversewn). For the right coronary button, a new ostium is fashioned on a suitable region of the graft for anastomosis.
Where appropriate, hemiarch or arch replacement with reimplantation of one- to three-branch vessels was performed based on the arch pathology. Antegrade or retrograde cerebral perfusion was used for cerebral protection during hypothermic circulatory arrest.