Cardiac outflow in the early developmental stage of a chick embryo is known to be highly variable depending on environmental temperature. To investigate the effects of environmental hypothermia on the blood flow in the outflow tract (OFT) of chick embryonic hearts, microscopic flow images were consecutively captured from chick embryos at HH stage 17 (2.5 days of incubation) at room temperature. Instantaneous velocity field information of blood flow in OFT was obtained using a micro-particle image velocimetry technique. The cyclic variations of the OFT vessel diameter and wall thickness were simultaneously measured. The experimental results show that environmental hypothermia causes bradycardia with a decrease in peak velocity during systole and the occurrence of backflow during diastole in the OFT. These abnormal phenomena seem to be attributed to the suppression of myocardial wall motion under hypothermic conditions.
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http://dx.doi.org/10.1016/j.mvr.2011.09.005 | DOI Listing |
Eur Heart J Case Rep
January 2025
Division of Cardiology, Department of Medicine, Kindai University Faculty of Medicine, 377-2 Ohno-Higashi, Osakasayama, Osaka 589-8511, Japan.
Background: The initial outcomes of transcatheter aortic valve replacement in patients with left ventricular outflow tract calcification are poor. Furthermore, balloon-expandable transcatheter aortic valve replacement is associated with an increased risk of annular rupture, and self-expandable transcatheter aortic valve replacement is associated with worse post-operative residual paravalvular leakage grades. Therefore, developing an optimal method for transcatheter aortic valve replacement for patients with left ventricular outflow tract calcification is desirable.
View Article and Find Full Text PDFEur Heart J Case Rep
January 2025
Department of Pediatric Cardiology, Osaka Women's and Children's Hospital, Izumi, Osaka 594-1101, Japan.
Background: A partial atrioventricular septal defect (AVSD) with a hypoplastic left ventricle and common atrium is a rare combination of cardiac anomalies that can be associated with Ellis-van Creveld (EVC) syndrome.
Case Summary: A female neonate with EVC syndrome was diagnosed with an unbalanced AVSD and hypoplastic left ventricle. Pulmonary artery banding and ductus ligation were performed at 23 days after birth.
Eur Heart J Case Rep
January 2025
Department of Cardiology, Azorg, Merestraat 80, 9300 Aalst, Belgium.
Background: Patients after transcatheter pulmonary valve implantation (TPVI) are at increased risk for infective prosthetic valve endocarditis. Diagnosis of infective endocarditis (IE) following TPVI is particularly difficult due to impaired visualization of the transcatheter pulmonary valve (TPV) with echocardiography [Delgado V, Ajmone Marsan N, de Waha S, Bonaros N, Brida M, Burri H, et al. 2023 ESC guidelines for the management of endocarditis.
View Article and Find Full Text PDFCPT Pharmacometrics Syst Pharmacol
January 2025
Huashan Hospital, Fudan University, Shanghai, China.
Mavacamten is a cardiac myosin inhibitor for adults with obstructive hypertrophic cardiomyopathy (HCM). Dose optimization is performed 4 weeks after starting mavacamten, guided by periodic echo measurements of Valsalva left ventricular outflow tract gradient (VLVOTg) and left ventricular ejection fraction (LVEF). Previously, a population pharmacokinetic (PPK) model was developed and exposure-response (E-R) of VLVOTg (efficacy) and LVEF (safety) was used to identify the mavacamten titration regimen with the optimal benefit/risk ratio, now included in the US prescribing information.
View Article and Find Full Text PDFHerzschrittmacherther Elektrophysiol
January 2025
Hannover Heart Rhythm Center, Department of Cardiology & Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany.
Background: The QRS axis of the electrocardiogram (ECG) is often considered in clinical practice, but its determination is frequently limited to a rough estimation, such as "normal", with left or right deviation, and superior or inferior in the case of premature ventricular complexes (PVCs). However, a more exact determination of the QRS axis may be warranted in certain scenarios, such as to determine the origin of PVCs more precisely, and is attainable by visual estimation using the hexaxial reference system.
Objectives: The aim of this study was to determine how well such an estimation of the QRS axis would correlate with the axis calculated by formulas.
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