A sudden postural change may produce symptoms or even syncope mainly due to orthostatic hypotension. To date, most hemodynamic studies in postural change focus on the response of static and definite postures. To quantify cardiovascular hemodynamics characteristics during continuous posture, we developed a three-dimensional fluid-structure interaction mathematical model of hemodynamics with cont...

The present study assessed the contribution of the renin-angiotensln system (RAS), dietary sodium, and cardiac output (CO) to the genesis of primate hypertension in a one-kidney model which was developed to test species-specific renin inhibitors. Reduction of renal perfusion pressure increased mean arterial pressure (MAP) from 105 ± 4 to 127 ± 3 mm Hg (p < 0.0005), associated with increased pla...

BACKGROUND We determined whether any significant association exists between change in late systolic cardiac load with time, estimated by radial pressure waveform analysis, and development of cardiac hemodynamic stress in individuals with preserved cardiac function. METHODS Brachial-ankle pulse wave velocity, radial augmentation index (rAI), first peak of the radial pressure waveform (SP1), sy...

Previous studies in normotensive subjects have shown a slight decline in resting left ventricular pump function and midwall contractility with aging. We examined the relations of age to these variables and to peripheral resistance and vascular stiffness in 272 asymptomatic, unmedicated adults (25 to 80 years old) who had uncomplicated essential hypertension. Cardiac and carotid ultrasound and c...