Recurrent embolic strokes due to antiphospholipid syndrome and non-bacterial thrombotic endocarditis in a patient with basal cell carcinoma

Non-Bacterial Thrombotic Endocarditis (NBTE) is a common form of aseptic thrombotic endocarditis that primarily affects mitral valves and less frequently aortic valves. NBTE is caused by systemic inflammatory …  Read More

Flaw-insensitive fatigue resistance of chemically fixed collagenous soft tissues

Sci Adv. 2023 Mar 3;9(9):eade7375. doi: 10.1126/sciadv.ade7375. Epub 2023 Mar 3.

ABSTRACT

Bovine pericardium (BP) has been used as leaflets of prosthetic heart valves. The leaflets are sutured on metallic stents and can survive 400 million flaps (~10-year life span), unaffected by the suture holes. This flaw-insensitive fatigue resistance is unmatched by synthetic leaflets. We show that the endurance strength of BP under cyclic stretch is insensitive to cuts as long as 1 centimeter, about two orders of magnitude longer than that of a thermoplastic polyurethane (TPU). The flaw-insensitive fatigue resistance of BP results from the high strength of collagen fibers and soft matrix between them. When BP is stretched, the soft matrix enables a collagen fiber to transmit tension over a long length. The energy in the long length dissipates when the fiber breaks. We demonstrate that a BP leaflet greatly outperforms a TPU leaflet. It is hoped that these findings will aid the development of soft materials for flaw-insensitive fatigue resistance.

PMID:36867693 | PMC:PMC9984180 | DOI:10.1126/sciadv.ade7375

Comparison of population characteristics and clinical outcomes of patients with type B aortic dissection or aortic intramural hematoma underwent thoracic endovascular aortic repair: a propensity score-matched analysis

Survival and aortic-related adverse events after thoracic endovascular aortic repair (TEVAR) for aortic intramural hematoma (IMH) and aortic dissection (AD) are controversial. We aimed to assess the preoperati…  Read More