A glutaraldehyde preserved valved bovine jugular xenograft mounted in a nitinol 'Z' stent, expandable from 7 to 28 mm of internal diameter, was evaluated in vitro (column of water developing a pressure of 45 mmHg and a mock loop including a pulsatile pump) and in vivo in five adult pigs with intra-vascular ultrasound to measure the inferior vena cava diameter via a retroperitoneal access. Throu...

Knowledge of the relationship between structure and function of the normal pulmonary arterial tree is necessary for understanding normal pulmonary hemodynamics and the functional consequences of the vascular remodeling that accompanies pulmonary vascular diseases. In an effort to provide a means for relating the measurable vascular geometry and vessel mechanics data to the mean pressure-flow re...

OBJECTIVES We analyzed whether radiographically demonstrated anterior inferior cerebellar artery (AICA) vascular compression of the cochleovestibular nerve in asymmetric hearing loss could be correlated to either the symptomatic ear or to cochlear nerve diameter. METHODS We undertook a retrospective case-control study in which patients were enrolled into a database if audiometry demonstrated ...

We compared the branches and trunk of rat superior mesenteric artery (SMA) with respect to extracellular pH (pHo)-dependent changes in vascular contractility. Decreases in pHo from 7.8 to 6.4 significantly reduced apparent affinity (pD2) to norepinephrine (NE) and maximal contraction by NE, which were more prominent in larger-diameter arteries. On the other hand, decreases in pHo significantly ...

uous real-time, cross-sectional imaging of blood vessels. We used this imaging catheter to compare intraluminal ultrasound with cineangiography in the measurement of vascular dimensions in animals and to assess the intraobserver and interobserver variability of the technique. Segmental deformation of vessel anatomy was produced by stenoses created with a tissue ligature or by balloon dilation. ...

We examined the effects of thrombosis on vascular tone in vivo, using small mesenteric arteries of rats (about 300 microns i.d.) and a video recording system attached to a microscope. To induce thrombosis we damaged the vessel wall over a short segment by compression and exposed the media to the bloodstream. A thrombus mainly consisting of platelets gradually enlarged at the damaged site and ca...

cGMP regulates vascular smooth muscle tone and arterial wall response to proliferative signals. We determined plasma cGMP and carotid artery intima-media thickness (IMT) and diameter in 84 asymptomatic men submitted to investigation of their cardiovascular risk profiles. Plasma cGMP was positively associated with IMT (P<0.01) and diameter (P<0.05), independently of coexisting risk factors. Thes...

The diameter of resistance arteries has a profound effect on the distribution of microvascular blood flow and the control of systemic blood pressure. Here, we review mechanisms that contribute to the regulation of resistance artery diameter, both acutely and chronically, their temporal characteristics, and their interdependence. Furthermore, we hypothesize the existence of a remodeling continuu...

Vascular structures adapt to changes in blood flow by adjusting their diameter accordingly. The factors mediating this process are only beginning to be identified. We have recently established a mouse model of arterial remodeling in which flow in the common carotid artery is interrupted by ligation of the vessel near the carotid bifurcation, resulting in a dramatic reduction in vessel diameter ...

Evaluation of elastic properties of major arteries is subject of great interest with respect to the development of vascular diseases. In this study changes in diameter and cross-sectional area, stress-strain elastic modulus and stiffness of the common carotid arteries in healthy and atherosclerotic women and men were evaluated by using indirect end pressure changes. Variations in diameter and c...