Anti-TAV polyclonal antibody [AP]

Turner syndrome (TS) is a common genetic disorder in females with high incidence of ascending aortic dilatation and even dissection occurring as early as in the second decade. Known risk factors (RF) are bicuspid aortic valves (BAV), coarctation of the aorta (CoA), and arterial hypertension. Since 10% of dissections occur in patients without RF, an intrinsic aortic wall abnormality has been postulated. This study aimed to investigate the elasticity of the ascending aorta as a surrogate marker of aortic wall texture. Forty-six pediatric patients with genetically proven TS were prospectively examined for the morphology of their aortic valve, and size and elasticity indices of the adjacent aorta. Cohorts of 46 female subjects with tricuspid aortic valves (TAV) and ten non-syndromic females with BAV were investigated as separate control groups. Comparison of healthy controls with TS patients revealed significantly deteriorated elasticity indices in those with TS. Furthermore, normalized aortic dimensions were greater in TS patients, but dilatations of the ascending aorta with z-score levels above two were restricted to those with BAV (14/46). Deteriorated elasticity indices were measured in TS patients, independent of aortic dilatation, BAV, and CoA, and were comparable to those of patients with isolated, non-syndromic BAVs. By measuring elasticity levels as a surrogate for aortic wall texture, we were able to gather evidence that TS presents with an intrinsic abnormality of the ascending aorta even in patients without concomitant BAV, CoA or dilatations as early as in childhood.

Background. Equipoise of transcatheter aortic valve replacement with surgical aortic valve replacement in intermediate-risk patients has been demonstrated. As transcatheter aortic valve replacement usage expands, questions regarding long-term durability become paramount. Valve design impacts durability with regions of increased leaflet stress being vulnerable to early failure. However, transcatheter aortic valve (TAV) leaflet stresses are unknown. The objective of this study was to determine stent and leaflet stresses of second-generation balloon-expandable TAV. Methods. Commercial 29-mm Edwards Sapien XT (Edwards Lifesciences, Irvine, CA) valves underwent high-resolution microcomputed tomography scanning to develop precise three-dimensional geometric mesh. Compressed and uncompressed TAVs were modeled under systemic pressure using finite element software. Material properties of stent were based on cobalt-chromium, whereas those for leaflets were obtained from surgical bioprostheses. Results. Maximum and minimum principal stresses on uncompressed Sapien XT TAV were 1.63 MPa and -0.36 MPa on leaflets and 93.3 MPa and -105.6 MPa on stent at diastolic pressure. Peak leaflet stress was observed at commissural tips where leaflets connected to the stent. For compressed TAV to 26 mm, maximum and minimum principal stresses were 1.55 MPa and -0.63 MPa on leaflets and 526.1 MPa and -902.2 MPa on stent at diastolic pressure. Peak leaflet stress was located at similar position and also along the suture line with the Dacron (C. R. Bard, Haverhill, PA). Conclusions. Stress analysis of two extreme deployed geometries of 29-mm Edwards Sapien XT using exact geometry from high-resolution scans demonstrated that peak stresses for TAV leaflets were present at commissural tips where leaflets were attached. These regions would be mostly likely to initiate degeneration. (C) 2017 by The Society of Thoracic Surgeons