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 ...