OBJECTIVE To determine the effects of angiotensin converting enzyme (ACE) inhibitors in hypertensive patients with aortic valve stenosis (AS). DESIGN Observational, drug withdrawal, single blinded study, with randomisation of the order of tests. SETTING Hypertension and asymptomatic AS. PATIENTS AND INTERVENTIONS 20 patients (aged 73 (9) years, valve area 0.7 (0.3) cm2, left ventricular e...

We have investigated the prevalence of hypertension and the response of blood pressure to operation in 87 patients with lone aortic valve disease who underwent aortic valve replacement. In patients with aortic stenosis alone 26% were hypertensive pre-operatively (age and sex adjusted blood pressure greater than 160 systolic and or greater than 95 mmHg diastolic) and 24% were hypertensive post-o...

BACKGROUND Pressure recovery is the variable increase in lateral pressure downstream from a stenotic orifice. The magnitude and clinical significance of pressure recovery in aortic valve stenosis are poorly defined. METHODS AND RESULTS We obtained high-fidelity pressure and velocity recordings in 11 patients with isolated significant aortic valve stenosis at the time of diagnostic cardiac cat...

heat exchangers are the critical components of refrigeration and liquefaction processes. selection of appropriate operational conditions for cryogenic recuperative heat exchanger and expansion valve operating in joule-thomson cooling system results in improving the performance and efficiency. in the current study, a straightforward procedure is introduced to design an efficient joule-thomson co...

In this study a computerised system was used which continuously measured air pressure, interface pressure and pressure-time cycle characteristics of an alternating pressure air cushion (APAC), and calculated the time the interface pressure remained below three chosen thresholds of 20, 40 and 60 mm Hg. Ten healthy volunteers were used to evaluate the pressure relieving characteristics of four AP...

This review highlights aspects of calcific aortic valve disease that encompass the entire range of aortic valve disease progression from initial cellular changes to aortic valve sclerosis and stenosis, which can be initiated by changes in blood flow (hemodynamics) and pressure across the aortic valve. Appropriate hemodynamics is important for normal valve function and maintenance, but pathologi...

Background Patients undergoing forefoot surgery often require specific footwear to relieve the operated area. Post-operative footwear can be very different in relation to the amount of weight born by the forefoot [1,2]. While these special shoes are intended to be worn for short periods following surgery, a compromise must be found between level of comfort and functionality. In this study the i...

BACKGROUND The evaluation of prosthetic valves is very difficult with two-dimensional transthoracic echocardiography alone. Doppler and color flow imaging as well as transesophageal echocardiography are more reliable to detect prosthetic valve dysfunction. However, Doppler study sometimes tends to be misleading due to the load-depending characteristics of peak and mean pressure gradients. The p...

Although the Codman-Hakim programmable valve is one of most popular shunt systems used in the clinical practice for the treatment of hydrocephalus, malfunctions related with this system have been also reported which lead to underdrainage or overdrainage of the cerebrospinal fluid. While obstruction of the ventricular catheter by tissue materials or hematoma and catheter disconnection are relati...