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 ...

BACKGROUND Presence of a tracheostomy tube often decreases the patient's ability to communicate and to tolerate oral intake. The initial tracheostomy tube change is often recommended between day 7 and 14 post insertion. Local guidelines permit tracheostomy tube change 5 days after insertion. OBJECTIVE We hypothesized that changing tracheostomy tubes before day 7 is associated with earlier use...

The purpose of a prosthetic cardiac valve is to restore the function of a diseased aortic or mitral valve, and its role in haemodynamics is a passive one: the opening and closing of such a valve is strictly regulated by the pressure differences in the cardiac chambers which communicate through this valve. Therefore we consider that a prosthetic valve should be tested under conditions simulating...

Three patients with normal hearts and no pulmonary abnormality had neonatal tricuspid regurgitation causing cardiorespiratory distress and cyanosis. The signs of tricuspid regurgitation resolved over a few weeks. In the acute phase echocardiography showed gross dilatation of the right atrium and ventricle. The interatrial septum bulged into the left atrium during the whole cardiac cycle. Dopple...

OBJECTIVE To confirm the validity of the calculation in MVA applying the method of Doppler pressure half-time directly in left atrial (LA) and pulmonary capillary pressure curve. METHODS Thirty-five patients with mitral valve stenosis underwent percutaneous mitral valvotomy (PMV) using the Cribier method with MVA measurement made using the traditional methods (Gorlin and echo-Doppler) and thi...

UNLABELLED Percutaneous balloon aortic valvuloplasty (BAV) was a rare procedure in catheterization laboratories because of its limited prognostic impact. The recent advent of transcatheter aortic valve implantation (TAVI) has led to a resurgence of BAV, opening the way to a new indication as a bridge to TAVI. Herein, we reported an 83-year-old man with critical aortic valve stenosis and pulmona...