PURPOSE We aimed to determine the correlation between flow characteristics of the proximal pulmonary arteries and vena cava obtained by 3.0 T phase-contrast magnetic resonance imaging (MRI) and hemodynamic characteristics by right heart catheterization in patients with chronic thromboembolic pulmonary hypertension. MATERIALS AND METHODS Twenty consecutive patients with chronic thromboembolic ...

BACKGROUND Vasovagal syncope is usually associated with a sudden drop of blood pressure and/or heart rate. However, occasionally the symptoms of syncope induced by orthostatic stress testing are not associated with obvious haemodynamic changes. The mechanisms of syncope in these patients are not clear. AIM To evaluate changes in cerebral blood flow velocities during orthostatic stress testing...

In this paper, we present methods for 3D visualization and quantitative measurements of retinal blood flow in rats by the use of optical microangiography imaging technique (OMAG). We use ultrahigh sensitive OMAG to provide high-quality 3D RBF perfusion maps in the rat eye, from which the Doppler angle, as well as the diameters of blood vessels, are evaluated. Estimation of flow velocity (i.e. a...

OBJECTIVES The main objective of this study was to assess the blood flow rate and velocity in coronary artery stenosis using intracoronary frequency domain optical coherence tomography (FD-OCT). A correlation between fractional flow reserve (FFR) and FD-OCT derived blood flow velocity is also included in this study. METHODS & RESULTS A total of 20 coronary stenoses in 15 patients were assesse...

We used a novel phase-resolved optical Doppler tomographic (ODT) technique with very high flow-velocity sensitivity (10microm/s) and high spatial resolution (10microm) to image blood flow in port-wine stain (PWS) birthmarks in human skin. In addition to the regular ODT velocity and structural images, we use the variance of blood flow velocity to map the PWS vessels. Our device combines ODT and ...

OBJECTIVE We aimed to examine the relationship between serum uric acid levels and left atrial appendage (LAA) peak flow velocity, an indicator of the mechanical functions of the LAA, and atrial fibrillation (AF). SUBJECTS AND METHODS Transesophageal echocardiography was performed before cardioversion in 153 patients with AF. The patients were categorized into 2 groups based on their LAA blood...

BACKGROUND Left ventricular hypertrophy is associated with an increased risk of cardiovascular morbidity and mortality. Previous studies have shown that patients with left ventricular hypertrophy develop electrocardiographic changes and left ventricular dysfunction during acute hypotension, and suggest that the lower end of autoregulation may be shifted upwards. AIM To measure coronary blood ...

Background Bicuspid aortic valve (BAV) is often associated with aortic stenosis, resulting in high velocity blood flow in the ascending aorta, with slow flow areas in the dilated aorta or adjacent vessels. Similarly, Marfan syndrome patients develop aortic root dilatation and regurgitation with both high and low velocity blood flow. 4D flow MRI is typically acquired with a velocity encoding (ve...

Ankle exercises are commonly used to facilitate venous return in the lower extremity and to prevent deep vein thrombosis. Moreover, the respiratory cycle affects venous return. This study examined the effects of ankle exercise combined with deep breathing on the blood flow velocity in the femoral vein. Twenty healthy males (mean age 21.3 years), who had no medical history of lower extremity dis...