Health related quality of life of patients following mechanical valve replacement surgery for rheumatic mitral stenosis in Tanzania

The assessment of outcomes of interventions based on the patient’s perspective using patient-reported outcome measures (PROMs) has been increasingly highlighted in clinical practice. However, health related qu…  Read More

Mid term freedom from atrial fibrillation following hybrid ablation, a systematic review and meta analysis

Atrial Fibrillation (AF) is a common tachyarrhythmia affecting 33 million people worldwide. Hybrid AF ablation utilises a surgical (epicardial) ablation followed by an endocardial catheter-based ablation. The …  Read More

Hemocompatibility tuning of an innovative glutaraldehyde-free preparation strategy using riboflavin/UV crosslinking and electron irradiation of bovine pericardium for cardiac substitutes

Biomater Adv. 2023 Apr;147:213328. doi: 10.1016/j.bioadv.2023.213328. Epub 2023 Feb 4.

ABSTRACT

Hemocompatibility tuning was adopted to explore and refine an innovative, GA-free preparation strategy combining decellularization, riboflavin/UV crosslinking, and low-energy electron irradiation (SULEEI) procedure. A SULEEI-protocol was established to avoid GA-dependent deterioration that results in insufficient long-term aortic valve bioprosthesis durability. Final SULEEI-pericardium, intermediate steps and GA-fixed reference pericardium were exposed in vitro to fresh human whole blood to elucidate effects of preparation parameters on coagulation and inflammation activation and tissue histology. The riboflavin/UV crosslinking step showed to be less efficient in inactivating extracellular matrix (ECM) protein activity than the GA fixation, leading to tissue-factor mediated blood clotting. Intensifying the riboflavin/UV crosslinking with elevated riboflavin concentration and dextran caused an enhanced activation of the complement system. Yet activation processes induced by the previous protocol steps were quenched with the final electron beam treatment step. An optimized SULEEI protocol was developed using an intense and extended, trypsin-containing decellularization step to inactivate tissue factor and a dextran-free, low riboflavin, high UV crosslinking step. The innovative and improved GA-free SULEEI-preparation protocol results in low coagulant and low inflammatory bovine pericardium for surgical application.

PMID:36764200 | DOI:10.1016/j.bioadv.2023.213328

Syndecan-4 Functionalization Reduces the Thrombogenicity of Engineered Vascular Biomaterials

Ann Biomed Eng. 2023 Apr 18. doi: 10.1007/s10439-023-03199-w. Online ahead of print.

ABSTRACT

Blood-biomaterial compatibility is essential for tissue repair especially for endovascular biomaterials where small-diameter vessel patency and endothelium formation is crucial. To address this issue, a composite biomaterial termed PFC fabricated from poly (glycerol sebacate), silk fibroin, and collagen was used to determine if functionalization with syndecan-4 (SYN4) would reduce thrombogenesis through the action of heparan sulfate. The material termed, PFC_SYN4, has structure and composition similar to native arterial tissue and has been reported to facilitate the binding and differentiation of endothelial colony-forming cells (ECFCs). In this study, the hemocompatibility of PFC_SYN4 was evaluated and compared with non-functionalized PFC, electrospun collagen, ePTFE, and bovine pericardial patch (BPV). Ultrastructurally, platelets were less activated when cultured on PFC and PFC_SYN4 compared to collagen where extensive platelet degranulation was observed. Quantitatively, 31% and 44% fewer platelets adhered to PFC_SYN4 compared to non-functionalized PFC and collagen, respectively. Functionalization of PFC resulted in reduced levels of complement activation compared to PFC, collagen, and BPV. Whole blood clotting times indicated that PFC_SYN4 was less thrombogenic compared with PFC, collagen, and BPV. These results suggest that syndecan-4 functionalization of blood-contacting biomaterials provides a novel solution for generating a reduced thrombogenic surface.

PMID:37071281 | DOI:10.1007/s10439-023-03199-w

Redo mitral surgery after coronary artery bypass grafts under hyperkalemic hypothermia using thoracotomy and axillary artery cannulation in a patient with functioning bilateral internal thoracic arteries and atheromatous aorta

Redo mitral valve surgery using resternotomy after coronary artery bypass grafting (CABG) is challenging as previous CABG with patent internal thoracic artery (ITA) poses a risk of injury due to dense adhesion…  Read More