PubMed HealthSearch

PubMed · 8573985

Recent progress in quantitative echocardiography.

Abstract

Substantial progress has been made recently in quantitating a variety of functional or morphologic parameters with echocardiography. Doppler techniques for measuring regurgitant flow rate and regurgitant orifice area in mitral and tricuspid regurgitation have become well established, along with other Doppler measures of regurgitation severity, such as proximal jet width. Doppler measurement of diastolic flow propagation in the left ventricle is emerging as a promising, albeit fascinatingly complex way of looking at diastolic function. Doppler velocimetry has been extended to wall motion, yielding color maps of tissue, an entirely new tool for assessing myocardial function and its timing. In the field of two-dimensional data processing, automatic on-line boundary detection based on integrated ultrasound backscatter has been used for volume and cardiac output calculations. Finally, three-dimensional reconstruction of cross-sectional images now has been well validated for in vivo measurements of heart cavity volumes and masses.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

F Flachskampf. 1995. Recent progress in quantitative echocardiography.. https://doi.org/10.1097/00001573-199511000-00013

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Echocardiographic and radionuclide pulmonary blood flow patterns after transcatheter closure of patent ductus arteriosus.

BACKGROUND: Transcatheter occlusion of patent ductus arteriosus (PDA) has been associated with protrusion of the occluder device into the left pulmonary artery (LPA). This study was conducted to evaluate the significance of occluder protrusion and its implications for potential obstruction of the LPA and associated decrease of left lung perfusion. METHODS AND RESULTS: Fifty-two patients underwent successful transcatheter PDA occlusion over a period of 5 years. In this study, 49 were reexamined between March and June 1995. In addition to clinical and echocardiographic examination, lung scintigraphy was performed. Protrusion into the LPA was present in 5 of 49 patients (10%). In these patients, maximal flow velocity in the LPA was significantly (P < .01) increased. Decreased left lung perfusion, defined as < 40% of total pulmonary blood flow, was found in 7 of 49 patients (14%). Although mean left pulmonary perfusion was significantly (P = .02) decreased in patients with protrusion, there was considerable overlap with patients without protrusion, and only a weak correlation was found (r = -.35, P = .01) between flow-velocity and left lung perfusion. CONCLUSIONS: Our results demonstrate that protrusion of the device in the LPA is an infrequent finding. If present, it is associated with increased maximal flow velocity in the LPA and diminished left lung perfusion. However, echocardiography and lung scintigraphy are weakly correlated: Increased maximal blood flow velocities in the proximal LPA proved to be a poor indicator or impaired left lung perfusion. Also, decreased perfusion occurs in the absence of echocardiographic evidence of device protrusion.

Blood Flow Velocity

Neutrophil adhesion to 24-hour IL-1-stimulated endothelial cells under flow conditions.

In this study, we examine neutrophil adhesion under flow conditions to cultured HUVEC stimulated for 4 or 24 h with IL-1. Interactions are measured using videomicroscopy and a parallel-plate flow system which is capable of distinguishing primary adhesion and rolling from secondary (firm) adhesion. We find that after 24 h, E-selectin does not contribute to primary adhesion, in contrast to a significant contribution after 4 h. Endothelial cell P-selectin does not contribute at either time point. Blocking or removing L-selectin from the neutrophil surface decreases adhesion 50 to 70% at either time point, and neuraminidase treatment of neutrophils decreases adhesion by 85%. These results suggest that after a 24-h stimulation, primary adhesion depends on a distinct selectin-like interaction in which a HUVEC receptor binds carbohydrates on neutrophil glycoproteins, including L-selectin. We also find that secondary adhesion in this system can be inhibited 90% with Ab blockade of CD18/ICAM-1 interactions after a 24-h stimulation, and that a combination of IL-1 and IL-4 selectively down-regulates the pathway for primary adhesion at 24 h. These results demonstrate that neutrophils adhere using different receptor pathways following 4- and 24-h stimulations, and provide experimental data characterizing some properties of the receptors involved. One of the pathways that is evident at 24 h appears to be a novel selectin-like interaction.

Blood Flow Velocity