Variable valve timing allows improvements of internal combustion engines and can be achieved by camless actuation technology. In this paper we consider an electromechanical valve (EMV) actuator. One of the main problems in the EMV actuator is the noise and wear associated with high contact velocities during the closing and opening of the valve. The contact velocity of the actuator parts can be ...

Many problems and complications associated with heart valves are related to the dynamic behavior of the valve and the resultant unsteady flow patterns. An accurate depiction of the spatial and temporal velocity and rms distributions imparts better understanding of flow related valve complications, and may be used as a guideline in valve design. While the generalized correlation between increase...

Echocardiographic assessment prior to valve surgery is crucial for clinical decision making, timing of surgery, planning the adequate surgical therapy and predicting the patient's outcome. Description of transvalvular velocities is not enough for sending a patient to the operating room. There are specific functional and morphological characteristics of each valve dysfunction that have to be add...

Abstract Aim Mitral valve disease (MVD) is a heart valvular defect associated with significant morbidity and mortality. Individual patient management depends on symptomatic disease, fitness type of pathology. Surgical intervention remains the standard for definitive management. The optimal time to operate debated considerations earlier surgical include reduced risk surgery co-morbidity preventi...

The timing of surgery in patients with mitral regurgitation (MR) and aortic regurgitation (AR) continues to elicit uncertainty and considerable controversy. Some patients will incur myocardial structural changes, pulmonary hypertension, or arrhythmias before they manifest symptoms, with the risk that these adverse endpoints will not be reversible after valve repair or replacement. Imaging to as...

Degenerative mitral valve disease often leads to leaflet prolapse due to chordal elongation or rupture, and resulting in mitral valve regurgitation. Guideline referral for surgical intervention centres primarily on symptoms and ventricular dysfunction. The recommended treatment for degenerative mitral valve disease is mitral valve reconstruction, as opposed to valve replacement with a bioprosth...