Aortic root replacement: what is in your wallet?

Infective endocarditis is an uncommon but complex disease, which has an annual incidence of 3–7 cases per 100,000 person years. Although an uncommon condition, the mortality from invasive endocarditis has been demonstrated to be as high as 30% at 30 days of diagnosis [1]. Galeone et al. [2] present their long-term outcomes of cryopreserved aortic homograft implantation for complex invasive endocarditis of the aortic valve. Their report includes 104 patients with 94% follow-up with a mean follow-up duration of 8 years. In the follow-up period, 26% (25 patients) of patients required late reoperation, the majority of whom (17/25 or 68%) was required for structural valve degeneration. A bioprosthetic aortic valve was used in 20 cases while 3 had a reoperative root replacement with a new homograft. The authors should be commended for their thorough follow-up of this patient cohort. Several options exist when dealing with aortic valve endocarditis. The first decision that must be addressed is whether the aortic root needs to be replaced due to invasion and damage to the aortic annulus or if only the valve cusps themselves are affected by the infectious process. In the case of root replacement the use of stented bioprosthetic valved conduits, mechanical valved conduits, stentless valves and cryopreserved homografts have all been described and can be performed with reasonable success [3–5]. Cryopreserved valved homografts have numerous advantages especially in the setting of invasive/destructive endocarditis including a favourable haemodynamic profile, low risk of thromboembolism without need for anticoagulation and perhaps most importantly for this cohort, increased ability to conform to the reconstructed annulus and aortomitral continuity after aggressive debridement that is often required for extensive valve and annular involvement. In certain situations where these particular advantages are necessary, there is no better choice for reconstruction and this publication along with others demonstrates predictable and acceptable outcomes [6, 7]. The cryopreserved homograft, however does have certain limitations, most importantly availability, as it cannot be mass produced in the same way as mechanical or bioprosthetic valves. More importantly, as we move further into the era of transcatheter heart valve therapies, there continually has to be considered for the technical implementation of valve-in-valve implantation with transcatheter aortic valves (TAVR) for structural valve degeneration given the high-risk nature of redo reoperative aortic root replacement surgery. Several studies have attempted to explore the challenges of transcatheter aortic valve replacement in failed aortic homografts. These challenges include a lack of anatomic markers for stentless valves or homografts as compared to stented valves [8, 9]. Other technical challenges to valve-in-valve TAVR are the degenerative valve pathology predominantly being regurgitation in stentless valves and homografts as opposed to the stenosis that predominates in stented pericardial valves [10]. We recognize that these considerations are secondary to the patient surviving and recovering from the initial insult of endocarditis, yet with outcomes such as those reported by Galeone et al. the idea of lifelong management of aortic valve disease cannot fall by the wayside. Ibrahim Sultan and Derek Serna-Gallegos’s institution receives research funding from Abbott, Atricure, Artivion, Edwards, Boston Scientific and Medtronic. There was no personal renumeration. These are unrelated to this manuscript. There was no funding provided for this work.