Study population
In this period, a total of 252 patients underwent repair for acute TAAD. The institution operates a regional referral system from associated nearby emergency departments for cases with TAAD. The on-call cardiothoracic consultant alternates on a rota basis. The standard care is immediate transfer upon discussion with the referring physician and review of relevant imaging, followed by planning for emergent surgery.
Only patients undergoing aortic root replacement (ARR) were included. Patients were subclassified as having i) porcine ARR (PAR); or ii) composite valve-graft (CVG) root replacement. The prosthesis used in the former group was the Freestyle porcine aortic root (Medtronic, Minneapolis, MN).
The primary indication for ARR was the presence of an intimal tear in the aortic root. Other indications were aortic root diameter >4.5cm, known connective tissue disease, aortic valve pathology and coronary dissection. For the purpose of this study, patients undergoing a valve-sparing root replacement or interposition graft (with or with aortic valve replacement) were excluded.