Introduction:
Bentall and De Bono described aortic root replacement with a composite valve conduit in their seminal paper in 1968(1). The Bentall procedure underwent several modifications over the following decades and remained the standard of care for addressing aortic root aneurysms(2, 3). However, it was realized that there was a subset of patients with aortic root pathology confined only to the aortic sinuses with normal aortic cusp anatomy and valve function; in this cohort of patients it is conceivable that addressing the aortic wall pathology while preserving the native valve function would be advantageous. Based on this observation Sir Magdi introduced the remodelling procedure, replacing the sinuses of valsava while preserving the valve leaflets(4). Subsequently, the reimplantation procedure was developed to address the limitation of the remodelling technique in stabilising the aortic annulus(5, 6).
In Type A aortic dissection, the aortic valve cusps are often normal which makes the application valve conserving techniques to patients with Type A Acute Aortic Dissection very appealing (TAAAD)(7). The enthusiasm for valve sparing root replacement (VSRR) is driven by reoperation rates following supracomissural aortic replacement in TAAAD being as high as 44% in young patients; conversely, in the same cohort of patients who had root aortic root replacement the freedom from root reintervention was 100% at 7 years; furthermore, replacement of the aortic valve with prosthesis is associated with risks related to anticoagulation for mechanical valves and structural valve degeneration of bioprostheses(8, 9).
In this paper we discuss -in patients with TAAAD- when should the root be replaced, selecting the right patients for VSRR, techniques of VSRR, lessons learnt from our experience at Emory, and outcomes of VSRR in patients with TAAAD.