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- Hanséus, Katarina, et al.
(författare)
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Analysis of atrioventricular plane movements by Doppler tissue imaging and m-mode in children with atrial septal defects before and after surgical and device closure.
- 2002
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Ingår i: Pediatric Cardiology. - : Springer Science and Business Media LLC. - 0172-0643 .- 1432-1971. ; 23:2, s. 152-159
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Tidskriftsartikel (refereegranskat)abstract
- Our objective was to compare the effects of surgical and device closure of atrial septal defects (ASDs) on atrioventricular plane function. In healthy individuals, both short- and long-axis motion contribute to ventricular pump function. Short-axis function (i.e., the amplitude and velocity of atrioventricular plane movements) may be evaluated by M-mode and Doppler tissue imaging. The study group consisted of 19 children with ASD of the secundum type before and after surgical (n = 12) or device (n = 7) closure and 10 healthy controls. Surgical and device closures were uncomplicated and all defects were completely closed. Registrations of atrioventricular plane systolic and diastolic amplitude and velocity were made from the tricuspid and the mitral annulus and from the septum in the apical four-chamber view. Comparisons were made between examinations before and after closure, between the two subgroups of patients treated by surgical and device closure, respectively, and between the patient group and the control groups. Before ASD closure, all measurements were normal or near normal. After surgery, systolic amplitudes and velocities of the tricuspid annulus and in the septum decreased significantly, whereas no changes were seen in the device group. Less marked changes were seen in diastolic measurements. However, in the surgical group significant decrease to subnormal values were found in the tricuspid annulus and in the septum, which may indicate a decreased diastolic function postoperatively. Mitral valve annulus amplitude and velocity were not affected by the treatment. Atrioventricular function is normal in children with right ventricular volume overload. The decrease to subnormal values after open-heart surgery is not seen after device closure of the ASD, indicating that surgery affects right ventricular function.
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- Ressner, Marcus, 1967-, et al.
(författare)
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Effects of ultrasound contrast agents on Doppler tissue velocity estimation
- 2006
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Ingår i: Journal of the American Society of Echocardiography. - : Elsevier BV. - 0894-7317 .- 1097-6795. ; 19:2, s. 154-164
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Tidskriftsartikel (refereegranskat)abstract
- The combination of Doppler tissue imaging and myocardial contrast echocardiography has the potential to provide information about motion and perfusion of the myocardium in a single examination. The purpose of this study was to establish how the presence of ultrasound contrast agent (UCA) affects measurements of Doppler tissue velocities in vivo and in vitro. We performed echocardiography in 12 patients with ischemic heart disease before and immediately after a slow intravenous infusion of the UCA Optison, using color Doppler tissue imaging to examine the effect of contrast agents in vivo. The myocardial peak systolic velocities and their integrals were analyzed in digitally stored cineloops before and after contrast administration. To distinguish between methodologic and physiologic factors affecting the measurement of tissue velocity in vitro, experiments with a rotating disk and a flow cone phantom were also carried out for the 3 contrast agents: Optison, Sonovue, and Sonazoid. in vivo results show that the values for peak systolic velocity increased by about 10% during contrast infusion, from mean 5.2 +/- 1.8 to 5.7 +/- 2.3 cm/s (P = .02, 95% confidence interval 2%-16%). The increase in myocardial peak systolic velocities was verified in experimental models in which the UCA increased the estimated mean velocity in the order of 5% to 20% for the motion interval of 5 to 7 cm/s, corresponding to the myocardial velocities studied in vivo. The response was similar for all 3 contrast agents and was not affected by moderate variations in concentration of the agent. We have shown that the presence UCA will affect Doppler tissue measurements in vivo and in vitro. The observed bias is presumed to be an effect of harmonic signal contribution from rupturing contrast agent microbubbles and does not indicate biologic or physiologic effects.
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- Wagstrom, Elle, et al.
(författare)
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The Cardiac State Diagram As A Novel Approach For The Evaluation Of Pre- And Post-Ejection Phases Of The Cardiac Cycle In Asphyxiated Fetal Lambs
- 2013
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Ingår i: Ultrasound in Medicine and Biology. - : Elsevier BV. - 0301-5629 .- 1879-291X. ; 39:9, s. 1682-1687
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate myocardial wall motion using echocardiography and color-coded tissue velocity imaging and to generate a cardiac state diagram for evaluation of the duration of the pre- and post-ejection phases in asphyxiated fetal lambs. Six near-term lambs were partly exteriorized and brought to cardiac arrest through asphyxia. Echocardiography measurements were recorded simultaneously with arterial blood sampling for lactate and blood gases. All fetal lambs exhibited prolongation of the pre- and post-ejection phases at the time when the most pronounced changes in lactate concentration and pH occurred. The mean change in duration of the pre- and post-ejection phases for all fetal lambs was 36 +/- 7 ms (p < 0.002) and 77 +/- 17 ms (p < 0.019), respectively, and the percentage change was 50% (p < 0.001) and 38% (p < 0.049), respectively. As asphyxia progressed in fetal lambs, the duration of the pre- and post-ejection phases increased. The cardiac state diagram has the potential to be a comprehensible tool for detecting fetal asphyxia. (E-mail: elle.wagstrom@karolinska.se) (C) 2013 World Federation for Ultrasound in Medicine & Biology.
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- Willenheimer, Ronnie, et al.
(författare)
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Definition av diastolisk hjärtsvikt
- 2007
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Ingår i: Läkartidningen. - 0023-7205 .- 1652-7518. ; 104:34, s. 2333-2337
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Tidskriftsartikel (refereegranskat)
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