Biodegradable materials for surgical management of infective endocarditis: new solution or a dead end street?

Abstract

BackgroundOne third of patients with infective endocarditis will require operative intervention. Given the superiority of valve repair over valve replacement in many indications other than endocarditis, there has been increasing interest and an increasing number of reports of excellent results of valve repair in acute infective endocarditis. The theoretically ideal material for valve repair in this setting is non-permanent, “vanishing” material, not at risk of seeding or colonization. The goal of this contribution is to review currently available data on biodegradable materials for valve repair in infective endocarditis.DiscussionRigorous electronic and manual literature searches were conducted to identify reports of biodegradable materials for valve repair in infective endocarditis. Articles were identified in electronic database searches of Medline, Embase and the Cochrane Library, using a predetermined search strategy. 49 manuscripts were included in the review. Prosthetic materials needed for valve repair can be summarized into annuloplasty rings to remodel the mitral or tricuspid annulus, and patch materials to replace resected valvar tissue. The commercially available biodegradable annuloplasty ring has shown interesting clinical results in a single-center experience; however further data is required for validation and longer follow-up. Unmodified extra-cellular matrix patches, such as small intestinal submucosa, have had promising initial experimental and clinical results in non-infected valve repair, although in valve repair for endocarditis has been reported in only one patient, and concerns have been raised regarding their mechanical stability in an infected field.SummaryThese evolving biodegradable devices offer the potential for valve repair with degradable materials replaced with autologous tissue, which could further improve the results of valve repair for infective endocarditis. This is an evolving field with promising experimental or initial clinical results, however long-term outcomes are lacking and further data is necessary to validate this theoretically interesting approach to infective endocarditis.

Performance of the ADAPT-Treated CardioCel® Scaffold in Pediatric Patients With Congenital Cardiac Anomalies: Medium to Long-Term Outcomes

“…However, when used without glutaraldehyde fixation, it shrinks, develops fibrosis and tends to stretch when exposed to high cardiovascular pressure, with reports of aneurysm formation at the site of the repair (13). The main advantage of glutaraldehyde fixation is that it improves the biostability of autologous and xenogeneic pericardium through collagen crosslinking, but with the potential consequences of residual toxic aldehydes which could result in late calcification (5,15). However, structural degeneration and dystrophic calcification remain limiting factors in terms of the longevity and clinical effectiveness of these bioprosthetic substitutes (11,12,16).…”

Evaluation of Infection Resistance of Biodegradable versus Conventional Annuloplasty Rings in an in vivo Rat Subcutaneous Model

“…It was shown that the Kalangos-Bioring® dissolved within 6 months and was replaced by autologous fibrous tissue within 12 months in a juvenile pig model, and it allows the growth of the annulus within normal physiological limits [35]. On the other hand, a lack of blood contact due to a subendocardial implantation technique and replacement by a native fibrotic reactive tissue are important features of the BAR (Kalangos-Bioring®) that support its lower infection potential and its effect on long-term infection prevention [10,11,12,13,14]. In addition, in 2013, Daghighi et al [36] stated that the use of degradable biomaterials was a clinically effective strategy to reduce infection risk in the view of biomedical engineers.…”

“…A biodegradable annuloplasty ring (BAR) (Kalangos-Bioring®) is a tool mainly developed for pediatric heart operations and formed by a monofilament of biodegradable poly-1,4-dioxanone [8,9]. Its implantation technique and structure (intra-annular and nonporous, respectively) are different from those of the CAR, and these characteristics may increase its resistance to peri- and postoperative infections [10,11,12,13,14]. …”