During a previous investigation and during routine clinical Doppler echocardiography velocities distal to normal valves were found to be increased in patients with congenital heart disease. To investigate this observation the velocity proximal and distal to cardiac valves was recorded in 56 patients with congenital heart disease. No detectable pressure gradient had been found across these valve...

Present prosthetic heart valves, while hemodynamically effective, remain limited by progressive structural deterioration of tissue valves or the burden of chronic anticoagulation for mechanical valves. An idealized valve prosthesis would eliminate these limitations. Polymeric heart valves (PHVs), fabricated from advanced polymeric materials, offer the potential of durability and hemocompatibili...

There is an increased risk of thromboembolism, anticoagulant-related hemorrhage, fetal-wastage and congestive cardiac failure in pregnant women with mechanical heart valves. In order to have a good outcome, the care of such patients must necessarily be multidisciplinary and in a well- equipped centre with adequate support services .One such patient who had mechanical mitral and aortic valves re...

Tissue engineered heart valves are a promising alternative for current heart valve replacements. However, the mechanical properties of these valves are insufficient for implantation at the aortic position [1]. Collagen orientation is important to improve the mechanical properties of tissue engineered valves. Two-photon laser-scanning microscopy allows us to study the influence of strain on coll...

The most characteristic componems of the intercellular matrix, or ground substance, of connective tissue are the highly polymerized acid mucopolysaccharides. Meyer and Rapport (1) distinguish five such acid mucopolysaccharides isolated from ground substance: three chondroitin sulfates (A, B, and C), hyaluronic acid, and hyaluronosulfate. These polymers have become of particular interest in rece...

BACKGROUND The management of pregnant patients with mechanical heart valves remains challenging because there are no large randomised studies to provide guidelines for effective anticoagulant therapy. Both vitamin K antagonists and heparins may be associated with maternal and foetal adverse events. METHOD The Southern African Society of Thrombosis and Haemostasis reviewed available literature...

Multipotent neural crest cells (NCCs) are a major extracardiac component of cardiovascular development. Although recognized as contributing cells to the arterial valves at early developmental stages, NCC persistence in the valves at later times or in the adult heart is controversial. We analyzed NCC persistence and contributions to both semilunar and atrioventricular (AV) valves in the mature h...

Sound spectroanalysis was carried out for diagnosis of malfunctioning prosthetic heart valves in 50 cases, which consisted of 31 mitral, 14 aortic, 4 mitral+aortic and 1 tricuspid valve replacements with the age ranging from 17 to 57 years. Types of prosthetic valves used in this series were Starr-Edwards silicon ball valves, metal ball valves, disc valves, Kay-Shiley valves, Smeloff-Cutter val...

patients underwent 262 valve replacements with frame-mounted autologous fascia lata valves in the aortic, mitral, and/or tricuspid positions at the National Heart Hospital. A single fascia lata valve was inserted in 146 patients and multi-valve replacement was performed in 55 instances. Hospital and late mortality are comparable with that following other procedures of heart valve replacement. O...

INTRODUCTION Turbulence, characterized by velocity fluctuations, is a sign of suboptimal hemodynamics in prosthetic heart valves [1]. Turbulence causes pressure drops and exposes endothelial cells and blood constituents to abnormal stresses which can lead to blood trauma and promote the pathogenesis of atherosclerosis. Phase-contrast MRI (PC-MRI) has previously been shown to be valuable for the...