Browsing Bergen Open Research Archive by Author "Hjertaas, Johannes Just"
Now showing items 1-8 of 8
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Impact of aortic valve stenosis on myocardial deformation in different left ventricular levels: A three-dimensional speckle tracking echocardiography study
Hjertaas, Johannes Just; Einarsen, Eigir; Gerdts, Eva; Kokorina, Marina Victorovna; Moen, Christian Arvei; Urheim, Stig; Saeed, Sahrai; Matre, Knut (Journal article; Peer reviewed, 2023)Background: Global systolic left ventricular (LV) myocardial function progressively declines as degenerative aortic valve stenosis (AS) progresses. Whether this results in uniformly distributed deformation changes from ... -
Impact of arterio–ventricular interaction on first-phase ejection fraction in aortic stenosis
Einarsen, Eigir; Hjertaas, Johannes Just; Gu, Haotian; Matre, Knut; Chowienczyk, Philip J.; Gerdts, Eva; Chambers, John B.; Saeed, Sahrai (Peer reviewed; Journal article, 2020)Aims: First-phase ejection fraction (EF1), the EF at the time to peak aortic jet velocity, has been proposed as a novel marker of peak systolic function in aortic stenosis (AS). This study aimed to explore the association ... -
Is strain by Speckle Tracking Echocardiography dependent on user controlled spatial and temporal smoothing? An experimental porcine study
Moen, Christian A.; Salminen, Pirjo-Riitta; Dahle, Geir O.; Hjertaas, Johannes Just; Grong, Ketil; Matre, Knut (Peer reviewed; Journal article, 2013-08-22)Background Speckle Tracking Echocardiography (STE) strain analysis relies on both spatial and temporal smoothing. The user is often allowed to adjust these smoothing parameters during analysis. This experimental study ... -
A left ventricular phantom for 3D echocardiographic twist measurements
Hjertaas, Johannes Just; Matre, Knut (Peer reviewed; Journal article, 2020)Traditional two-dimensional (2D) ultrasound speckle tracking echocardiography (STE) studies have shown a wide range of twist values, also for normal hearts, which is due to the limitations of short-axis 2D ultrasound. The ... -
Markers of Subclinical Atherosclerosis in Severe Obesity and One Year after Bariatric Surgery
Kovac, Nina; Grymyr, Lisa Marie Dale; Gerdts, Eva; Nadirpour, Saied; Nedrebø, Bjørn Gunnar; Hjertaas, Johannes Just; Matre, Knut; Cramariuc, Dana (Journal article; Peer reviewed, 2022)Background: Aortic valve sclerosis (AVS), mitral valve sclerosis (MVS), remodeling of major arteries, and increased pericardial fat are associated with subclinical atherosclerosis. We assessed these markers of atherosclerosis ... -
Measurement of left ventricular deformation using 3D echocardiography
Hjertaas, Johannes Just (Doctoral thesis, 2023-06-05)Bakgrunn: 3D speckle tracking ekkokardiografi (STE) er en hjerteultralydmetode som gir mulighet for måling av deformasjonsparametere, som strain, rotasjon, tvist og torsjon. Den største begrensningen for 3D STE er lav tids- ... -
Myocardial function in aortic stenosis - insights from radial multilayer Doppler strain
Cramariuc, Dana; Gerdts, Eva; Hjertaas, Johannes Just; Cramariuc, Alexandru; Davidsen, Einar Skulstad; Matre, Knut (Peer reviewed; Journal article, 2015-02-19)Background Left ventricular (LV) radial tissue Doppler imaging (TDI) strain increases gradually from the subepicardial to the subendocardial layer in healthy individuals. A speckle tracking echocardiography study suggested ... -
One-year impact of bariatric surgery on left ventricular mechanics: results from the prospective FatWest study
Grymyr, Lisa Marie Dale; Nadirpour, Saied; Gerdts, Eva; Nedrebø, Bjørn Gunnar; Hjertaas, Johannes Just; Matre, Knut; Cramariuc, Dana (Journal article; Peer reviewed, 2021)Aims Patients with severe obesity are predisposed to left ventricular (LV) hypertrophy, increased myocardial oxygen demand, and impaired myocardial mechanics. Bariatric surgery leads to rapid weight loss and improves ...