Small Degenerated Surgical Bioprosthetic Valve should be Treated with SupraAnnular Valve-in-Valve Transcatheter Aortic Valve Replacement

Background: Patient-prothesis mismatch (PPM) is a serious potential complication following surgical aortic valve replacement (SAVR). If it develops, valve-in-valve transcatheter aortic valve replacement (TAVR) is a reasonable therapeutic option. However, there is low evidence on the management of small degenerated surgical bioprosthetic valves, not prone to balloon-valve fracture (BVF). Case Presentation: This case report presents a successful valve-in-valve TAVR in acute heart failure due to degenerative surgical bioprosthetic valve Trifecta (21 mm) that is not susceptible to BVF. Standard preparation for transfemoral TAVR with a self-expandable valve was conducted, including the over-the-wire pacing. Thereafter, a successful valve-in-valve primary implantation of the self-expanding, supra-annular valve Evolut R 26 (Medtronic™) has been achieved. Follow-up at 3 months showed mild paravalvular leak in the region with clinical and heart function improvements of the patient. Follow-up echocardiographic parameters showed the reduction of anterograde flow impairment and improved effective orifice area (~0.85 cm2/m2). Conclusion: In conclusion, supra-annular valve-in-valve TAVR is a potential therapeutic option for PPM of small degenerated surgical bioprosthetic valves which are not prone to BVF.

Uniformity in bioprosthetic mitral valve sizing -- when will we get there?

Much has changed since the introduction of surgical valve repair in the 1950s, from the introduction bioprosthetic valves to percutaneous approaches to valve repair. Yet, despite substantial advancements in bioprosthetic valve technology, there has been a lack of direct, independent comparison between bioprosthetic mitral valve devices, accompanied by a marked heterogeneity in approaches to the sizing and selection thereof. Wang et al. have hence endeavoured to evaluate, head-to-head, the technical successes and biomechanical outcomes associated with three different bioprosthetic mitral valves (Epic, Abbott, IL; Mosaic, Medtronic, MN; Mitris Resilia, Edwards Lifesciences, CA) in a porcine model, under standardised haemodynamic and anatomical conditions. With a robust experimental technique, they have made clear the heterogeneity in both sizing and biomechanical properties between bioprosthetic mitral valves, and have further emphasised the need for a uniform approach to the manufacturing and sizing of bioprosthetic valves.

Long-Term Stability and Biocompatibility of Pericardial Bioprosthetic Heart Valves

The use of bioprostheses for heart valve therapy has gradually evolved over several decades and both surgical and transcatheter devices are now highly successful. The rapid expansion of the transcatheter concept has clearly placed a significant onus on the need for improved production methods, particularly the pre-treatment of bovine pericardium. Two of the difficulties associated with the biocompatibility of bioprosthetic valves are the possibilities of immune responses and calcification, which have led to either catastrophic failure or slow dystrophic changes. These have been addressed by evolutionary trends in cross-linking and decellularization techniques and, over the last two decades, the improvements have resulted in somewhat greater durability. However, as the need to consider the use of bioprosthetic valves in younger patients has become an important clinical and sociological issue, the requirement for even greater longevity and safety is now paramount. This is especially true with respect to potential therapies for young people who are afflicted by rheumatic heart disease, mostly in low- to middle-income countries, for whom no clinically acceptable and cost-effective treatments currently exist. To extend longevity to this new level, it has been necessary to evaluate the mechanisms of pericardium biocompatibility, with special emphasis on the interplay between cross-linking, decellularization and anti-immunogenicity processes. These mechanisms are reviewed in this paper. On the basis of a better understanding of these mechanisms, a few alternative treatment protocols have been developed in the last few years. The most promising protocol here is based on a carefully designed combination of phases of tissue-protective decellularization with a finely-titrated cross-linking sequence. Such refined protocols offer considerable potential in the progress toward superior longevity of pericardial heart valves and introduce a scientific dimension beyond the largely disappointing ‘anti-calcification’ treatments of past decades.

Predicting the Ideal Valve Size During Aortic Valve Replacement with Rapid Deployement Bioprosthetic Valves. Is Intraoperative Transesophageal Echocardiogram Reliable?

Objective: To describe experience with using intraoperative Transesophageal Echocardiography to reliably predict the size of the rapid deployment prosthetic valve by measuring the native aortic annulus Methods: Retrospective review of single institution series of patients undergoing Aortic Valve Replacement with Rapid Deployement Bioprosthetic Valves. Included were patients that had their native aortic valve replaced either isolated or as part of any additional procedure. Aortic annulus was measured prior to initiation of the operation using transesophageal echocardiography (TEE). Correlation analysis was conducted between Echocardiographic annular measurements and actual implanted valve sizes. Results: Twenty five patients underwent rapid deployment valve implantation in the aortic position. Of these, 36% of patients had the same size valve as the measured aortic annulus, 48% of patients had a valve implanted that was 1 mm different, and 16% of patients had 2 mm difference. The mean annular size based was 22.4 mm (range: 21-28 mm). The mean valve size implanted was 23.3 mm (range: 21-27 mm). There was no statistically significant difference between the mean annular measurement and the valve size selected (0.9 mm , p = 0.8). Conclusion: TEE can further enhance valve sizing and guidance through a proper and safe deployment. Although evident in our experience, larger scale studies are needed to further elucidate conclusions on the importance of avoiding under-sizing valves.