The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, te...

This is especially true for exhaust valves, due to the high temperature environment to which the valve is exposed. In a paper presented at the GMRC 2007 Gas Machinery Conference[1], it has been shown that statistical techniques and histograms of valve vibration data can be used to identify valve faults that can lead to valve failures. This paper will discuss refinements made to the statistical ...

This study aimed to investigate the incidence, predictors, and clinical outcomes of cardiac tamponade after heart valve surgery. A total of 556 patients who underwent heart valve surgery in a single tertiary center between January 2010 and March 2012 were studied. All patients underwent transthoracic echocardiography (TTE) about 5 days after surgery and TTE was repeated regularly. Patients with...

BACKGROUND The long-term benefits of the maze procedure in patients with chronic atrial fibrillation undergoing mechanical valve replacement who already require lifelong anticoagulation remain unclear. METHODS AND RESULTS We evaluated adverse outcomes (death; thromboembolic events; composite of death, heart failure, or valve-related complications) in 569 patients with atrial fibrillation-asso...

Native aortic valve cusps are composed of collagen fibers embedded in their layers. Each valve cusp has its own distinctive fiber alignment with varying orientations and sizes of its fiber bundles. However, prior mechanical behavior models have not been able to account for the valve-specific collagen fiber networks (CFN) or for their differences between the cusps. This study investigates the in...

A 62-year-old woman presented with a sudden transient ischemic attack (TIA). Symptoms resolved within 2 hours of onset. Neurological evaluation and workout for etiology of the TIA was unremarkable. Her medical history included having a St. Jude mitral valve replacement for mitral regurgitation 10 years before presentation. The patient had been maintained on warfarin with INR levels generally in...

OBJECTIVES To describe the early and late outcomes of carcinoid patients undergoing surgical heart valve replacement. METHODS In a retrospective study, records of patients with symptomatic carcinoid heart disease referred for valve surgery between 1993 and 2010 at two academic centres were reviewed. The perioperative and postoperative outcomes were analysed. RESULTS Nineteen patients, with ...

To design more effective tissue-engineered heart valve replacements, the replacement tissue may need to mimic the biaxial stress-strain behavior of native heart valve tissue. This study characterized the planar biaxial properties of tissue-engineered valve leaflets and native aortic valve leaflets. Fibrin-based valve equivalent (VE) and porcine aortic valve (PAV) leaflets were subjected to incr...

The design and development of functional engineered tissues is dependent on multiple considerations, with biomechanics paramount for load-bearing constructs such as tissue engineered heart valves. As the cryopreserved allograft is the current standard for valve replacement in pediatric patients, identifying and quantifying essential structural–mechanical properties of the native valve leaflet i...

Ö o ( c p e fi ( ( t d v ( l With the advent of the Starr-Edwards mechanical mitral and aortic valves in the 1960s, the surgical era of the treatment of cardiac valvular disease began in earnest. Although considered definitive, valve replacement surgery effectively represents an exchange of the pathophysiology of severe valvular dysfunction for the diseases and complications associated with pro...