Month: September 2022

J Cardiovasc Dev Dis. 2022 Aug 22;9(8):282. doi: 10.3390/jcdd9080282.

ABSTRACT

Aortic stenosis is the most common valve disease requiring surgery or percutaneous treatment. Since the first-in-man implantation in 2002 we have witnessed incredible progress in transcatheter aortic valve implantation (TAVI). In this article, we review the technical aspects of TAVI development with a look at the future. Durability, low thrombogenicity, good hydrodynamics, biocompatibility, low catheter profile, and deployment stability are the attributes of an ideal TAVI device. Two main design types exist-balloon-expandable and self-expanding prostheses. Balloon-expandable prostheses use a cobalt-chromium alloy frame providing high radial strength and radiopacity, while the self-expanding prostheses use a nickel-titanium (Nitinol) alloy frame, which expands to its original shape once unsheathed and heated to the body temperature. The valve is sewn onto the frame and consists of the porcine or bovine pericardium, which is specially treated to prevent calcinations and prolong durability. The lower part of the frame can be covered by polyethylene terephthalate fabric or a pericardial skirt, providing better sealing between the frame and aortic annulus. The main future challenges lie in achieving lower rates of paravalvular leaks and new pacemaker implantations following the procedure, lower delivery system profiles, more precise positioning, longer durability, and a good hemodynamic profile. Patient-specific design and the use of autologous tissue might solve these issues.

PMID:36005446 | PMC:PMC9409777 | DOI:10.3390/jcdd9080282

J Vasc Surg Cases Innov Tech. 2022 May 3;8(2):300-304. doi: 10.1016/j.jvscit.2022.04.002. eCollection 2022 Jun.

ABSTRACT

Cryopreserved vein allografts are used as alternative conduits for infrainguinal bypass but are prone to aneurysmal degeneration. A 60-year-old man presented with a pulsatile, tender right groin mass 2 years after thrombosis of a cryopreserved vein jump graft emanating from a prosthetic axillary to profunda bypass. Intraoperatively, the aneurysm was consistent with isolated dilatation of the hood of the thrombosed cryopreserved vein graft. This was excised and repaired with bovine pericardial patch angioplasty. The patient recovered with no recurrence for 2 years. Aneurysmal degeneration of the cryopreserved vein allograft can occur even after graft thrombosis.

PMID:35669278 | PMC:PMC9166410 | DOI:10.1016/j.jvscit.2022.04.002

Biomolecules. 2022 Sep 2;12(9):1222. doi: 10.3390/biom12091222.

ABSTRACT

Recent advancements in regenerative medicine have enhanced the development of biomaterials as multi-functional dressings, capable of accelerating wound healing and addressing the challenge of chronic wounds. Hydrogels obtained from decellularized tissues have a complex composition, comparable to the native extracellular environment, showing highly interesting characteristics for wound healing applications. In this study, a bovine pericardium decellularized extracellular matrix (dECM) hydrogel was characterized in terms of macromolecules content, and its immunomodulatory, angiogenic and wound healing potential has been evaluated. The polarization profile of human monocytes-derived macrophages seeded on dECM hydrogel was assessed by RT-qPCR. Angiogenic markers expression has been evaluated by Western blot and antibody array on cell lysates derived from endothelial cells cultured on dECM hydrogel, and a murine in vivo model of hindlimb ischemia was used to evaluate the angiogenic potential. Fibroblast migration was assessed by a transwell migration assay, and an in vivo murine wound healing model treated with dECM hydrogels was also used. The results showed a complex composition, of which the major component is collagen type I. The dECM hydrogel is biocompatible, able to drive M2 phenotype polarization, stimulate the expression of angiogenic markers in vitro, and prevent loss of functionality in hindlimb ischemia model. Furthermore, it drives fibroblast migration and shows ability to facilitate wound closure in vivo, demonstrating its great potential for regenerative applications.

PMID:36139063 | PMC:PMC9496624 | DOI:10.3390/biom12091222

Foot Ankle Surg. 2022 Sep 5:S1268-7731(22)00170-9. doi: 10.1016/j.fas.2022.08.013. Online ahead of print.

ABSTRACT

BACKGROUND: Hallux rigidus (HR) is a degenerative arthritis of the first metatarsophalangeal joint (MTP1) with progressive loss of range of movement (ROM). Interposition arthroplasty (IA) is a technique widely used for the treatment of HR;however, few studies reported long-term clinical results. This study aims to report the clinical results of IA using a bovine pericardium collagen matrix for HR with a minimum 10-years follow-up.

METHODS: Thirty patients (31 feet) who underwent IA using a bovine pericardium collagen matrix from 2001 to 2009 were retrospectively evaluated with a mean follow up of 154.1 ± 28.6 (range 124-218) months. All HR ranged from grade II to grade III, according to Regnauld classification. All patients were clinically assessed with the American Orthopedic Foot and Ankle Society Hallux Metatarsophalangeal- Interphalangeal Scale, a pain Visual Analog Scale, and the Foot and Ankle Disability Index. Scores before and after treatment, respectively achieved from clinical records and clinical evaluation at final follow-up were compared.

RESULTS: At final follow-up, an improvement of all the considered scores (p < 0.01) was recorded. The overall rate of unsatisfying results was 16.1 %. Two (6.4 %) patients complained discomfort due to first ray shortening and 3 (9.7 %) cases of persistent metatarsal pain. There was one (3.2 %) case of Complex Regional Pain Syndrome (CPRS). No revision surgeries, infection, or other adverse events were reported.

CONCLUSION: Interposition arthroplasty using bovine collagenous membrane is a reliable solution for high-grade HR with durable results over 10 years in more than 80 % of patients.

PMID:36117005 | DOI:10.1016/j.fas.2022.08.013

Biomaterials. 2022 Sep 6;289:121782. doi: 10.1016/j.biomaterials.2022.121782. Online ahead of print.

ABSTRACT

Bioprosthetic heart valves (BHV) fabricated from heterograft tissue, such as glutaraldehyde pretreated bovine pericardium (BP), are the most frequently used heart valve replacements. BHV durability is limited by structural valve degeneration (SVD), mechanistically associated with calcification, advanced glycation end products (AGE), and serum protein infiltration. We investigated the hypothesis that anti-AGE agents, Aminoguanidine, Pyridoxamine [PYR], and N-Acetylcysteine could mitigate AGE-serum protein SVD mechanisms in vitro and in vivo, and that these agents could mitigate calcification or demonstrate anti-calcification interactions with BP pretreatment with ethanol. In vitro, each of these agents significantly inhibited AGE-serum protein infiltration in BP. However, in 28-day rat subdermal BP implants only orally administered PYR demonstrated significant inhibition of AGE and serum protein uptake. Furthermore, BP PYR preincubation of BP mitigated AGE-serum protein SVD mechanisms in vitro, and demonstrated mitigation of both AGE-serum protein uptake and reduced calcification in vivo in 28-day rat subdermal BP explants. Inhibition of BP calcification as well as inhibition of AGE-serum protein infiltration was observed in 28-day rat subdermal BP explants pretreated with ethanol followed by PYR preincubation. In conclusion, AGE-serum protein and calcification SVD pathophysiology are significantly mitigated by both PYR oral therapy and PYR and ethanol pretreatment of BP.

PMID:36099713 | DOI:10.1016/j.biomaterials.2022.121782