Search results for "Wall motion"
showing 10 items of 19 documents
Wall motion characteristic of the right pulmonary artery in the suprasternal echocardiogram
1980
This study describes the motion pattern of the right pulmonary artery (RPA) as it can be assessed from the suprasternal echocardiogram. The motion characteristic of the RPA is dependent on hemodynamic factors within the lumen of the RPA and those within the left atrium and the aortic arch. During atrial contraction the superior wall of the left atrium separates from the inferior wall of the RPA (IWRPA) and produces an "a" dip in the wall motion of the IWRPA. During isovolumic contraction the RPA is shifted upward (IC point). The incisura in the pulmonary artery pressure curve reflecting pulmonic valve closure can be seen by a sudden decrease in the diameter of the RPA (PC point). In conditi…
Prognostic implications of dipyridamole cardiac MR imaging: a prospective multicenter registry
2011
Purpose: To evaluate dipyridamole cardiac magnetic resonance (MR) imaging in the prediction of major events (MEs) in patients with ischemic chest pain in a large multicenter registry. Materials and Methods: Institutional ethics committee approval and written informed consent were obtained. A total of 1722 patients who were undergoing cardiac MR imaging for chest pain were included. Wall motion abnormalities (WMAs) at rest, hyperemia perfusion defect (PD), late gadolinium enhancement (LGE), and inducible WMA were analyzed (abnormal if more than one abnormal segment was seen) with the 17-segment model. A cardiac MR categorization was created: category 1, no PD, LGE, or inducible WMA; category…
Quality control of B-lines analysis in stress Echo 2020
2018
Background The effectiveness trial “Stress echo (SE) 2020” evaluates novel applications of SE in and beyond coronary artery disease. The core protocol also includes 4-site simplified scan of B-lines by lung ultrasound, useful to assess pulmonary congestion. Purpose To provide web-based upstream quality control and harmonization of B-lines reading criteria. Methods 60 readers (all previously accredited for regional wall motion, 53 B-lines naive) from 52 centers of 16 countries of SE 2020 network read a set of 20 lung ultrasound video-clips selected by the Pisa lab serving as reference standard, after taking an obligatory web-based learning 2-h module ( http://se2020.altervista.org ). Each te…
The new clinical standard of integrated quadruple stress echocardiography with ABCD protocol
2018
Abstract Background The detection of regional wall motion abnormalities is the cornerstone of stress echocardiography. Today, stress echo shows increasing trends of utilization due to growing concerns for radiation risk, higher cost and stronger environmental impact of competing techniques. However, it has also limitations: underused ability to identify factors of clinical vulnerability outside coronary artery stenosis; operator-dependence; low positivity rate in contemporary populations; intermediate risk associated with a negative test; limited value of wall motion beyond coronary artery disease. Nevertheless, stress echo has potential to adapt to a changing environment and overcome its c…
Comparison of Two- and Three-Dimensional Unenhanced and Contrast-Enhanced Echocardiographies Versus Cineventriculography Versus Cardiac Magnetic Reso…
2013
Contrast enhancement has been shown to improve detection of regional wall motion abnormalities (RWMA) in 2-dimensional (2D) echocardiography. This study determined the use of contrast enhancement in the setting of 3-dimensional (3D) echocardiography for definition of left ventricular RWMA compared with 2D echocardiography, cineventriculography, and cardiac magnetic resonance (CMR). In 63 patients, unenhanced and contrast-enhanced (SonoVue; Bracco Imaging S.p.A., Milan, Italy) 2D and 3D echocardiographies, CMR, and cineventriculography were performed. Hypokinesia in ≥1 segment defined the presence of RWMA. Interreader agreement (IRA) between 2 blinded off-site readers on presence of RWMA was…
Transthoracic and transesophageal echocardiography to diagnose ventricular septal rupture
1993
BACKGROUND Rapid and accurate diagnosis of ventricular septal rupture (VSR) remains difficult, and the monitoring of hemodynamic deterioration is a prerequisite for the institution of adequate therapy. The timing of surgical repair is a matter of controversy. METHODS Transthoracic, transesophageal, color Doppler, and contrast echocardiography were evaluated in 17 patients with VSR in whom the diagnosis was confirmed by catheterization, surgery, or necropsy. RESULTS Routine transthoracic echocardiography visualized VSR in four out of 17 patients and, with additional views, in 12 out of 17 patients. Color Doppler echocardiography identified the rupture in 15 out of 16, and contrast echocardio…
Midventricular dyskinesia during clozapine treatment?
2009
This is the case of a young man suffering from schizophrenia and treated with clozapine. He developed acute heart failure associated with pericardial effusion and midventricular dyskinesia with severe systolic dysfunction and left ventricular dilatation at echocardiogram, readily resolved after the suspension of clozapine therapy. The segmental wall motion abnormalities observed at echocardiogram in this case are peculiar and have never been described before. The possible cardiotoxic effects of clozapine have been reported previously in the literature. Because of its serious potential side effects this drug is not considered the first choice for treatment of schizophrenia. Before beginning …
Combined effect of magnetic field and charge current on antiferromagnetic domain-wall dynamics
2017
We theoretically examine a cross effect of magnetic field and charge current on antiferromagnetic domain wall dynamics. Since antiferromagnetic materials are largely insensitive to external magnetic fields in general, charge current has been shown recently as an alternative and efficient way to manipulate antiferromagnets. We find a new role of the magnetic field in the antiferromagnetic dynamics that appears when it is combined with charge current, demonstrating a domain wall motion in the presence of both field and current. We show that a spatially varying magnetic field can shift the current-driven domain-wall velocity, depending on the domain-wall structure and the direction of the fiel…
Geometrical control of pure spin current induced domain wall depinning.
2017
[EN] We investigate the pure spin-current assisted depinning of magnetic domain walls in half ring based Py/Al lateral spin valve structures. Our optimized geometry incorporating a patterned notch in the detector electrode, directly below the Al spin conduit, provides a tailored pinning potential for a transverse domain wall and allows for a precise control over the magnetization configuration and as a result the domain wall pinning. Due to the patterned notch, we are able to study the depinning field as a function of the applied external field for certain applied current densities and observe a clear asymmetry for the two opposite field directions. Micromagnetic simulations show that this …
Domain walls and ising-BLOCH transitions in parametrically driven systems.
2002
Parametrically driven systems sustaining sech solitons are shown to support a new kind of localized state. These structures are walls connecting two regions oscillating in antiphase that form in the parameter domain where the sech soliton is unstable. Depending on the parameter set the oppositely phased domains can be either spatially uniform or patterned. Both chiral (Bloch) and nonchiral (Ising) walls are found, which bifurcate one into the other via an Ising-Bloch transition. While Ising walls are at rest Bloch walls move and may display secondary bifurcations leading to chaotic wall motion.