The first prosthetic valve was implanted by Hufnagel in 1952 in a patient with aortic insufficiency. Since then, prosthetic valves have evolved into various mechanical and bioprosthetic shapes and sizes. Despite the excitement surrounding the current development of prosthetic heart valves, surgically implanted valves remain the mainstay of current practice, and this article discusses the hemody...

BACKGROUND The two most common causes of aortic stenosis are primary "degenerative" calcification of tricuspid aortic valves and secondary calcification of congenital bicuspid valves. T lymphocyte infiltration occurs in stenotic tricuspid aortic valves, indicating an inflammatory component, but it has not been shown whether it also occurs in stenotic bicuspid valves. OBJECTIVE To compare non-...

Background: The two most common causes of aortic stenosis are primary “degenerative” calcification of tricuspid aortic valves and secondary calcification of congenital bicuspid valves. T lymphocyte infiltration occurs in stenotic tricuspid aortic valves, indicating an inflammatory component, but it has not been shown whether it also occurs in stenotic bicuspid valves. Objective: To compare non-...

1. Permanent therapy with oral anticoagulants offers the most consistent protection in patients with mechanical heart valves. 2. Antiplatelet agents alone do not consistently protect patients with mechanical prosthetic heart valves, including patients in sinus rhythm with St. Jude Medical valves in the aortic position. 3. Levels of oral anticoagulants that prolong the INR to 2.0 to 3.0 appear s...

transcatheter aortic valve replacement (tavr) is a novel therapeutic intervention for the replacement of severely stenotic aortic valves in high-risk patients for standard surgical procedures. since the initial partner trial results, use of tavr has been on the rise each year. new delivery methods and different valves have been developed and modified in order to promote the minimally invasive p...

Although porcine aortic valves or pericardial tissue mounted on a stent have made implantation techniques easier, these valves sacrifice orifice area and increase stress at the attachment of the stent, which causes primary tissue failure. Optimizing hemodynamics to prevent patient-prosthetic mismatch and improve durability, stentless bioprostheses use was revived in the early 1990s. The purpose...

BACKGROUND AND OBJECTIVES The aim of this study was to assess mechanical valve function using 64-slice multidetector computed tomography (MDCT). SUBJECTS AND METHODS In 20 patients (mean age, 50+/-12 years; male-to-female ratio, 10:10), 30 St. Jude bileaflet mechanical valves (15 aortic and 15 mitral valves) were evaluated using MDCT. We selected images vertical and parallel to the mechanical...

introduction brucella endocarditis, although an uncommon complication of brucellosis, is the main cause of the mortality related to this disease. the best therapy is a combination of antibiotic administration with valve replacement. after treatment of the first episode of endocarditis, new infection may be occurred as a relapse or reinfection. case presentation in this report, we described a pa...

in this study it has been tried, to compare results and convergence rate of sensitivity analysis and conjugate gradient algorithms to reduce fuel consumption and increasing engine performance by optimizing the timing of opening and closing valves in xu7/l3 engine. in this study, considering the strength and accuracy of simulation gt-power software in researches on the internal combustion engine...