12,439 results match your criteria systole diastole


Myocardial T1 Values at 1.5 T: Normal Values for General Electric Scanners and Sex-Related Differences.

J Magn Reson Imaging 2021 Apr 13. Epub 2021 Apr 13.

Magnetic Resonance Imaging Unit, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy.

Background: No data are available about normal ranges for native T1 in human myocardium using General Electric (GE) scanners.

Purpose: To establish normal ranges for myocardial T1 values and evaluate regional variability and the influence of physiological factors.

Study Type: Prospective. Read More

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The CORolla device for energy transfer from systole to diastole: a novel treatment for heart failure with preserved ejection fraction.

Heart Fail Rev 2021 Apr 11. Epub 2021 Apr 11.

CorAssist Cardiovascular Ltd, Haifa, Israel.

It is estimated that 30 to 50% of heart failure patients have heart failure with preserved ejection fraction (HFpEF). Mortality is high in this patient population, and morbidity and rate of hospitalization are similar to those of heart failure patients with reduced ejection fraction (HFrEF). The management of patients with HFpEF is essentially empirical, limited, and disappointing. Read More

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Identification of intra-individual variation in intracranial arterial flow by MRI and the effect on computed hemodynamic descriptors.

MAGMA 2021 Apr 11. Epub 2021 Apr 11.

Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, USA.

Objectives: To determine the intra-individual flow variation in serially acquired studies, and the influence of this variation on subsequent hemodynamic simulations using the inlet flow as a boundary condition. Author: Kindly check and confirm whether the corresponding authors are correctly identified.Confirmed. Read More

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Cardiovascular magnetic resonance-assessed fast global longitudinal strain parameters add diagnostic and prognostic insights in right ventricular volume and pressure loading disease conditions.

J Cardiovasc Magn Reson 2021 Apr 1;23(1):38. Epub 2021 Apr 1.

National Heart Research Institute Singapore, National Heart Centre Singapore, 5 Hospital Drive, 169609, Singapore, Singapore.

Background: Parameters of myocardial deformation may provide improved insights into right ventricular (RV) dysfunction. We quantified RV longitudinal myocardial function using a fast, semi-automated method and investigated its diagnostic and prognostic values in patients with repaired tetralogy of Fallot (rTOF) and pulmonary arterial hypertension (PAH), who respectively exemplify patients with RV volume and pressure overload conditions.

Methods: The study enrolled 150 patients (rTOF, n = 75; PAH, n = 75) and 75 healthy controls. Read More

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Tanshinone IIA attenuates heart failure via inhibiting oxidative stress in myocardial infarction rats.

Mol Med Rep 2021 Jun 31;23(6). Epub 2021 Mar 31.

Emergency Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu 210029, P.R. China.

The purpose of the present study was to evaluate whether tanshinone IIA (TIIA) could treat cardiac dysfunction and fibrosis in heart failure (HF) by inhibiting oxidative stress. An HF model was induced by ligation of the left anterior descending artery to cause ischemia myocardial infarction (MI) in Sprague‑Dawley rats. Cardiac fibrosis was evaluated using Masson's staining, and the levels of collagen I, collagen III, TGF‑β, α‑smooth muscle actin (α‑SMA), matrix metalloproteinase (MMP) 2 and MMP9 were determined using PCR or western blotting. Read More

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Surgical ventricular restoration for rabbit dilated cardiomyopathy model: Preliminary study.

Res Vet Sci 2021 Mar 26;136:373-376. Epub 2021 Mar 26.

Department of Small Animal Clinical Sciences, School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai Midorimachi, Ebetsu, Hokkaido 069-8501, Japan; Yokohama Yamate Dog & Cat Medical Center, 27-4 Kasiwaba Nakaku, Yokohamasi, Kanagawaken 231-0866, Japan.

Dilated cardiomyopathy (DCM) is a common cardiovascular disease in dogs. It is primarily treated with beta-blockers. The aim of this preliminary study was to evaluate the efficacy of surgical ventricular restoration on daunorubicin-induced DCM in rabbits. Read More

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Fluid-structure interaction in a fully coupled three-dimensional mitral-atrium-pulmonary model.

Biomech Model Mechanobiol 2021 Mar 26. Epub 2021 Mar 26.

School of Mathematics and Statistics, University of Glasgow, Glasgow, G12 8SQ, UK.

This paper aims to investigate detailed mechanical interactions between the pulmonary haemodynamics and left heart function in pathophysiological situations (e.g. atrial fibrillation and acute mitral regurgitation). Read More

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Repeatability, reproducibility, and reference intervals for indices of right atrial longitudinal strain derived from speckle-tracking echocardiography in healthy dogs.

Am J Vet Res 2021 Apr;82(4):274-279

Objective: To determine repeatability, reproducibility, and reference intervals of indices of right atrial longitudinal strain (RALS) derived from speckle-tracking echocardiography (STE) in dogs without heart disease.

Animals: 110 client-owned dogs and 10 laboratory Beagles.

Procedures: To determine intraobserver within-day (repeatability) and interobserver (reproducibility) coefficients of variation, RALS during ventricular systole (ϵS), ventricular early diastole (ϵE), and atrial systole (ϵA), as derived with STE, were obtained by 2 investigators for 5 randomly selected client-owned dogs and analyzed by linear regression. Read More

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Quantification of Cardiac Kinetic Energy and Its Changes During Transmural Myocardial Infarction Assessed by Multi-Dimensional Seismocardiography.

Front Cardiovasc Med 2021 8;8:603319. Epub 2021 Mar 8.

Department of Cardiology, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium.

Seismocardiography (SCG) records cardiac and blood-induced motions transmitted to the chest surface as vibratory phenomena. Evidences demonstrate that acute myocardial ischemia (AMI) profoundly affects the SCG signals. Multidimensional SCG records cardiac vibrations in linear and rotational dimensions, and scalar parameters of kinetic energy can be computed. Read More

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All-systolic first-pass myocardial rest perfusion at a long saturation time using simultaneous multi-slice imaging and compressed sensing acceleration.

Magn Reson Med 2021 Mar 10. Epub 2021 Mar 10.

School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.

Purpose: To enable all-systolic first-pass rest myocardial perfusion with long saturation times. To investigate the change in perfusion contrast and dark rim artefacts through simulations and surrogate measurements.

Methods: Simulations were employed to investigate optimal saturation time for myocardium-perfusion defect contrast and blood-to-myocardium signal ratios. Read More

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Feasibility of a Dielectric Elastomer Augmented Aorta.

Adv Sci (Weinh) 2021 Mar 25;8(6):2001974. Epub 2021 Jan 25.

Integrated Actuators Laboratory École Polytechnique fédérale de Lausanne (EPFL) Neuchâtel 2000 Switzerland.

Although heart transplantation is a gold standard for severe heart failure, there is a need for alternative effective therapies. A dielectric-elastomer aorta is used to augment the physiological role of the aorta in the human circulatory system. To this end, the authors developed a tubular dielectric elastomer actuator (DEA) able to assist the heart by easing the deformation of the aorta in the systole and by increasing its recoil force in the diastole. Read More

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Atrial fibrillation is associated with large beat-to-beat variability in mitral and tricuspid annulus dimensions.

Eur Heart J Cardiovasc Imaging 2021 Mar 16. Epub 2021 Mar 16.

Department of Cardiovascular Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.

Aims: Beat-to-beat variability in cycle length is well-known in atrial fibrillation (Afib); whether this also translates to variability in annulus size remains unknown. Defining annulus maximal size in Afib is critical for accurate selection of percutaneous devices given the frequent association with mitral and tricuspid valve diseases.

Methods And Results: Images were obtained from 170 patients undergoing 3D echocardiography [100 (50 sinus rhythm (SR) and 50 Afib) for mitral annulus (MA) and 70 (35 SR and 35 Afib) for tricuspid annulus (TA)]. Read More

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Left atrial dysfunction in patients with obstructive sleep apnea: a combined assessment by speckle tracking and real-time three-dimensional echocardiography.

Ann Palliat Med 2021 Mar 3;10(3):2668-2678. Epub 2021 Mar 3.

Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai, China.

Background: At present, little research concerning the assessment of left atrial (LA) dysfunction in patients with obstructive sleep apnea (OSA) using a combined assessment by speckle tracking (STE) and real-time three-dimensional echocardiography (RT3DE) is available. The objective of this study was to evaluate the LA volume and function by STE and RT3DE in patients with OSA.

Methods: In our cohort study, ninety-two OSA patients and 50 healthy individuals were enrolled. Read More

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Multi-parametric approach to predict prosthetic valve size using CMR and clinical data: insights from SAVR.

Int J Cardiovasc Imaging 2021 Mar 10. Epub 2021 Mar 10.

Section of Cardiothoracic Surgery, Heart Center, Veterans Affairs Medical Center, Washington, DC, USA.

The purpose of this investigation was to characterize the CMR and clinical parameters that correlate to prosthetic valve size (PVS) determined at SAVR and develop a multi-parametric model to predict PVS. Sixty-two subjects were included. Linear/area measurements of the aortic annulus were performed on cine CMR images in systole/diastole on long/short axis (SAX) views. Read More

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Value of renal resistive index in covid-19 ARDS patients: an early inflammation alert for the lung-kidney cross-talk?

Recenti Prog Med 2021 03;112(3):216-218

Department of Anesthesia and Intensive Care Units, IRCCS Humanitas Research Hospital , Rozzano (MI), Italy - Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI), Italy.

We analysed RRI and other hemodynamic, re-spiratory and inflammation parameters in critically ill pa-tients affected by severe covid-19 with acute distress respi-ratory syndrome (ARDS) aiming at verifying their modifica-tions during supine and prone positioning and any mutual correlation or interplay with RRI. Read More

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Right Ventricular Flow Dynamics in Dilated Right Ventricles: Energy Loss Estimation Based on Blood Speckle Tracking Echocardiography-A Pilot Study in Children.

Ultrasound Med Biol 2021 Jun 6;47(6):1514-1527. Epub 2021 Mar 6.

Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway; Children's Clinic, St. Olav's University Hospital, Trondheim, Norway.

Using blood speckle tracking (BST) based on high-frame-rate echocardiography (HFRE), we compared right ventricle (RV) flow dynamics in children with atrial septal defects (ASDs) and repaired tetralogy of Fallot (rTOF). Fifty-seven children with rTOF with severe pulmonary insufficiency (PI) (n = 21), large ASDs (n = 11) and healthy controls (CTL, n = 25) were included. Using a flow phantom, we studied the effects of imaging plane and smoothing parameters on 2-D energy loss (EL). Read More

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Quantification of artifacts during cardiac magnetic resonance in patients with leadless Micra pacemakers.

J Cardiovasc Electrophysiol 2021 Mar 8. Epub 2021 Mar 8.

Department of Cardiology, Na Homolce Hospital, Prague, Czech Republic.

Introduction: When cardiac magnetic resonance (MR) is performed after previous leadless transcatheter pacemaker implantation, an image distortion has to be expected in the heart region and evaluation of myocardial tissue can be affected. In this clinical prospective study, we aim to assess the extent and impact of this artifact on individual ventricular segments and compare it to conventional pacing devices.

Methods: Total of 20 patients with leadless pacemaker placed in the right ventricle underwent cardiac MR imaging in a 1. Read More

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PIV Analysis of Haemodynamics Distal to the Frozen Elephant Trunk Stent Surrogate.

Cardiovasc Eng Technol 2021 Mar 5. Epub 2021 Mar 5.

Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, 8041, New Zealand.

Purpose: The Frozen Elephant Trunk (FET) stent is a hybrid endovascular device that may be implemented in the event of an aneurysm or aortic dissection of the aortic arch or superior descending aorta. A Type 1B endoleak can lead to intrasaccular flow during systole and has been identified as a known failure of the FET stent graft. The purpose was to develop in-vitro modelling techniques to enable the investigation of the known failure. Read More

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Right Ventricular Mass Quantification Using Cardiac CT and a Semiautomatic Three-Dimensional Hybrid Segmentation Approach: A Pilot Study.

Authors:
Hyun Woo Goo

Korean J Radiol 2021 Feb 2. Epub 2021 Feb 2.

Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.

Objective: To evaluate the technical applicability of a semiautomatic three-dimensional (3D) hybrid CT segmentation method for the quantification of right ventricular mass in patients with cardiovascular disease.

Materials And Methods: Cardiac CT (270 cardiac phases) was used to quantify right ventricular mass using a semiautomatic 3D hybrid segmentation method in 195 patients with cardiovascular disease. Data from 270 cardiac phases were divided into subgroups based on the extent of the segmentation error (no error; ≤ 10% error; > 10% error [technical failure]), defined as discontinuous areas in the right ventricular myocardium. Read More

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February 2021

Low Dose Curcumin Administered in Hyaluronic Acid-Based Nanocapsules Induces Hypotensive Effect in Hypertensive Rats.

Int J Nanomedicine 2021 24;16:1377-1390. Epub 2021 Feb 24.

Jagiellonian University, Jagiellonian Centre for Experimental Therapeutics (JCET), Krakow, 30-348, Poland.

Background: Vascular drug delivery becomes a promising direction in the development of novel therapeutic strategies in the treatment of cardiovascular pathologies, such as hypertension. However, targeted delivery of hydrophobic substances, with poor bioavailability, remains a challenge. Here, we described the hypotensive effects of a low dose of curcumin delivered to the vascular wall using hyaluronic acid-based nanocapsules. Read More

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Three-Dimensional Fluid Dynamical Features of Coronary Plaque Rupture Provoking Acute Coronary Syndrome.

J Atheroscler Thromb 2021 Mar 2. Epub 2021 Mar 2.

Division of Cardiology, Department of Medicine, Nihon University School of Medicine.

Aim: Coronary plaque rupture is the main cause of acute coronary syndrome (ACS), but the role of blood flow features around plaque rupture for ACS is still unknown. The present study aimed to assess the relationship between the geometric configuration of ruptured plaque and ACS occurrence using computational fluid dynamics (CFD) by moving particle method in patients with coronary artery disease.

Methods: In this study, 45 patients with coronary artery disease who underwent three-dimensional intravascular ultrasound (IVUS) and had a coronary ruptured plaque (24 plaques with provoked ACS, 21 without) were included. Read More

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Echocardiographic image multi-structure segmentation using Cardiac-SegNet.

Med Phys 2021 Mar 2. Epub 2021 Mar 2.

Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, 30322, USA.

Purpose: Cardiac boundary segmentation of echocardiographic images is important for cardiac function assessment and disease diagnosis. However, it is challenging to segment cardiac ventricles due to the low contrast-to-noise ratio and speckle noise of the echocardiographic images. Manual segmentation is subject to interobserver variability and is too slow for real-time image-guided interventions. Read More

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Transcatheter Heart Valve Downstream Fluid Dynamics in an Accelerated Evaluation Environment.

Ann Biomed Eng 2021 Feb 26. Epub 2021 Feb 26.

Department of Biomedical Engineering, The Pennsylvania State University, Chemical and Biomedical Engineering Building, 122, University Park, PA, 16802, USA.

Transcatheter aortic valve replacements (TAVRs) provide minimally invasive delivery of bioprosthetic heart valves (BHVs) for the treatment of aortic valve disease. While surgical BHVs show efficacy for 8-10 years, long-term TAVR durability remains unknown. Pre-clinical testing evaluates BHV durability in an ISO:5840 compliant accelerated wear tester (AWT), yet, the design and development of AWTs and their accuracy in predicting in vivo performance, is unclear. Read More

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February 2021

Hemodynamic interplay of vorticity, viscous energy loss, and kinetic energy from 4D Flow MRI and link to cardiac function in healthy subjects and Fontan patients.

Am J Physiol Heart Circ Physiol 2021 04 26;320(4):H1687-H1698. Epub 2021 Feb 26.

Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.

The purpose of this study was to directly assess (patho)physiology of intraventricular hemodynamic interplay between four-dimensional flow cardiovascular magnetic resonance imaging (4D Flow MRI)-derived vorticity with kinetic energy (KE) and viscous energy loss (EL) over the cardiac cycle and their association to ejection fraction (EF) and stroke volume (SV). Fifteen healthy subjects and thirty Fontan patients underwent whole heart 4D Flow MRI. Ventricular vorticity, KE, and EL were computed over systole (vorticity_vol, KE, and EL) and diastole (vorticity_vol, KE, and EL). Read More

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Walking for hypertension.

Cochrane Database Syst Rev 2021 02 24;2:CD008823. Epub 2021 Feb 24.

Medical Affairs Division, Hualien Armed Forces General Hospital, Hualien, Taiwan.

Background: Increased physical activity has been recommended as an important lifestyle modification for the prevention and control of hypertension. Walking is a low-cost form of physical activity and one which most people can do. Studies testing the effect of walking on blood pressure have revealed inconsistent findings. Read More

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February 2021

Prediction for future occurrence of type A aortic dissection using computational fluid dynamics.

Eur J Cardiothorac Surg 2021 Feb 23. Epub 2021 Feb 23.

Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Objectives: The actual underlying mechanisms of acute type A aortic dissection (AAAD) are not well understood. The present study aimed to elucidate the mechanism of AAAD using computational fluid dynamics (CFD) analysis.

Methods: We performed CFD analysis using patient-specific computed tomography imaging in 3 healthy control cases and 3 patients with AAAD. Read More

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February 2021

The influence of training status on right ventricular morphology and segmental strain in elite pre-adolescent soccer players.

Eur J Appl Physiol 2021 Feb 22. Epub 2021 Feb 22.

Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.

Cardiac modifications to training are a product of the genetic pre-disposition for adaptation and the repetitive haemodynamic loads that are placed on the myocardium. Elite pre-adolescent athletes are exposed to high-intensity training at a young age with little understanding of the physiological and clinical consequences. It is unclear how right ventricular (RV) structure and function may respond to this type of stimulus. Read More

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February 2021

Diastolic dysfunction and impaired cardiac output reserve in dysmetabolic nonhuman primate with proteinuria.

J Diabetes Complications 2021 Apr 5;35(4):107881. Epub 2021 Feb 5.

Crown Bioscience Inc., 6 West Beijing Road, Taicang, Jiangsu, China. Electronic address:

Background: Cardiorenal complications are common in patients with dysmetabolism and diabetes. The present study aimed to examine if a nonhuman primate (NHP) model with spontaneously developed metabolic disorder and diabetes develops similar complications to humans, such as proteinuria and cardiac dysfunction at resting condition or diminished cardiac functional reserve following dobutamine stress echocardiography (DSE).

Methods And Results: A total of 66 dysmetabolic and diabetic cynomolgus (Macaca fascicularis) NHPs were enrolled to select 19 NHPs (MetS) with marked metabolic disorders and diabetes (fasting blood glucose: 178 ± 18 vs. Read More

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Evaluation of Optimal Diastolic Blood Pressure Range Among Adults With Treated Systolic Blood Pressure Less Than 130 mm Hg.

JAMA Netw Open 2021 02 1;4(2):e2037554. Epub 2021 Feb 1.

Department of Cardiology, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China.

Importance: Extremely low diastolic blood pressure has been reported to be associated with increased adverse cardiovascular events (ie, the diastolic J-shape phenomenon); however, current US guidelines recommend an intensive blood pressure target of less than 130/80 mm Hg without mentioning the lower limits of diastolic blood pressure.

Objectives: To evaluate whether there is a diastolic J-shape phenomenon for patients with an treated systolic blood pressure of less than 130 mm Hg and to explore the safe and optimal diastolic blood pressure ranges for this patient population.

Design, Setting, And Participants: This cohort study analyzed outcome data of patients at high cardiovascular risk who were randomized to intensive or standard blood pressure control and achieved treated systolic blood pressure of less than 130 mm Hg in the Systolic Blood Pressure Intervention Trial (SPRINT) and Action to Control Cardiovascular Risk in Diabetes-Blood Pressure (ACCORD-BP) trial. Read More

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February 2021

The impact of cardiac afferent signaling and interoceptive abilities on passive information sampling.

Int J Psychophysiol 2021 Apr 11;162:104-111. Epub 2021 Feb 11.

Lab of Action & Body, Department of Psychology, Royal Holloway, University of London, UK; The Warburg Institute, School of Advanced Study, University of London, UK; Department of Behavioural and Cognitive Sciences, Faculty of Humanities, Education and Social Sciences, University of Luxembourg, Luxembourg.

A growing body of research suggests that perception and cognition are affected by fluctuating bodily states. For example, the rate of information sampling is coupled with cardiac phases. However, the benefits of such spontaneous coupling between bodily oscillations and decision-making remains unclear. Read More

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