Editorial: Long-term durability of biological aortic valves

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Editorial on the Research Topic Long-term durability of biological aortic valves

With over 6,000 total views and downloads to date, this short, but contributive article collection is dedicated to the still unsolved problem of Long Term Durability of Biological Aortic Valves. Each co-editor of this research topic contributed efficiently by writing, mentoring or editing high quality manuscripts, which underwent, thereafter, an independent and strict reviewing process. We thankfully transmit our respects to all authors but also to those very engaged reviewers who entirely contributed to enhance the quality of the papers, which were eventually published (see Table 1). Unfortunately, this process also discarded some other valuable contributions, which will surely find some opportunities to be published elsewhere.

Neither optimistic nor pessimistic about the studied question, the editorial line of the current research topic aims at being realistic and factual. Reflecting its broad spectrum, this paper collection includes one brief research report, two original research articles as well as two reviews.

Tissue valves, though biological by nature, are not utterly biocompatible and long-term durability is impaired by fatigue lesions as well as by calcifications, which are the ultimate consequences of immunological and inflammatory processes not so far from tissular rejection. By elegantly studying in vivo, the effects of antagonists of chemokine receptor type 2 on valvular calcifications, Chabry et al. stress on the importance of the inflammatory response to the durability of tissue valvular and suggest a potential preventive treatment of SVD in high risk patients. Though this approach is still very preliminary, we believe that it might prove to be interesting in future.

During the past few years, the common knowledge about the durability of biological valves has been challenged by the new VARC-3 consensus about the definition of tissue primary failure. Based on that, surgical series have to be updated to this new paradigm and to report their results accordingly. Adopting the VARC-3 definition consensus, Porto et al. report on the largest ever-published series of patients implanted with the new Edwards INSPIRIS RESILIA, a tissue valve device that aims at greatly improving biocompatibility of tissue valves. Though the follow-up duration is still limited, results are excellent and we eagerly await data from long term follow-up.

Because the definition of biological valve failure has evolved with the accuracy to detect tissular abnormalities with imaging techniques, VARC-3 now defines a Stage 1 structural valve deterioration (SVD) as morphological valve deterioration without significant hemodynamic changes. To investigate the potential role of cardiac magnetic resonance (CMR) imaging on the assessment of biological aortic valves, Vermes et al. performed a well-illustrated review, which demonstrates the value of CMR as a complementary tool when the results of valve evaluation by trans-thoracic or trans-esophageal echocardiography are equivocal or inconclusive for any reason.

Best practice guidelines, which aim at adhere closely to scientific evidences often end up to resume being best wishes when confronted to the market-driven real world practices. By studying tendencies in the implantation of biological or mechanical SAVR across a recent period in France, Caus et al. demonstrate an obvious shift towards biological SAVR in middle-aged patients and question the rationale for it with regards to the literature supporting guidelines. This situation is unlikely to reverse soon, if Western Europe is to follow trends in USA, where TAVI procedures are currently broadly performed in patients under 65-years-old.

We might be just one leaflet away from the ideal valve substitute, which would offers both biocompatibility and durability. Just before performing the first in man, Carrel et al. propose a comprehensive review of the TRIFLO valve and underline the importance of the reverse flow phase of current bi-leaflet mechanical valves in platelet activation and thrombosis formation. Therefore, it is more this peculiar hemodynamic characteristics, shared by all current mechanical prosthetic valves, than the nature of foreign material used to build them, which makes the need for permanent oral anticoagulation. Ultimately, optimizing the design of mechanical valves and adopting a tri-leaflet configuration could lead to obtain a cheap, universal, biocompatible and reliable valvular substitute to treat all forms of surgical valve disease worldwide.

We encourage the lectors of this editorial to take a look at all articles related to the current research topic of Long Term Durability of Biological Aortic Valves. We wish them to get during lecture as much pleasure as we have experienced when elaborating this collaborative work under the flag of Frontiers!