Blood flow pulsatility can be quantified using the concept of hemodynamic energy. Because ischemia-reperfusion injury is known to affect microcirculation as well as vascular tone detrimentally, we hypothesized that vascular tone changes after ischemia-reperfusion injury would influence pulsatility of the blood vessels. We investigated the changes in pulsatility after ischemia-reperfusion injury using hemodynamic energy parameters-energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE). Twenty-one New Zealand white male rabbits were divided into three groups. Ischemia group (I group, n = 7) underwent 3 hours of ischemia by clamping the abdominal aorta. Reperfusion group (I/R group, n = 7) underwent 2 hours of ischemia followed by 1 hour of reperfusion. Control group (C group, n = 7) underwent a sham procedure. Observed parameters were mean arterial pressure (MAP), mean blood flow (MBF), pulse pressure (PP), EEP, and SHE, measured at baseline, during ischemia (60 minutes after clamping), and reperfusion 5, 15, 30, and 60 minutes after clamp release. In I group, all parameters, except MBF, were higher during ischemia than at baseline. In I/R group, all except MBF were higher during ischemia. After reperfusion, MBF increased and the other parameters decreased. Interestingly, PP and EEP showed only minor changes during reperfusion (p = NS), whereas SHE decreased abruptly immediately after reperfusion and then gradually recovered to its baseline level. Surplus hemodynamic energy showed more significant changes than PP or EEP during reperfusion period (p < 0.05). In C group, no changes were noted throughout the observation period. Ischemia-reperfusion injury reduces vascular pulsatility. In this study, SHE was found to be a more sensitive hemodynamic energy parameter during ischemia-reperfusion injury than PP or EEP.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1097/MAT.0b013e3181dd4efe | DOI Listing |
Eur J Radiol Open
June 2025
Department of Radiology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, 1678 Dong Fang Road, Shanghai 200127, PR China.
Background: The Fontan procedure is a surgical intervention designed for patients with single ventricle physiology, wherein the systemic venous return is redirected into the pulmonary circulation, thereby facilitating passive pulmonary blood flow without the assistance of ventricular propulsion. Consequently, long-term follow-up of individuals who have undergone the asymptomatic Fontan procedure is essential.
Objectives: The aims of this investigation were to: 1) examine the impact of flow components and kinetic energy (KE) parameters on hemodynamic disturbances in asymptomatic Fontan patients and control group; 2) Assess left ventricular diastolic dysfunction through the analysis of 4D flow parameters across different Fontan sub-groups; 3) Compare intracardiac flow parameters among Fontan sub-groups based on morphological features of the left ventricle (LV) and right ventricle (RV).
Sci Rep
January 2025
University of Ulsan, 93 Daehak-ro, Nam-gu, Ulsan, 680-749, Republic of Korea.
This study employed large eddy simulation (LES) with the wall-adapting local eddy-viscosity (WALE) model to investigate transitional flow characteristics in an idealized model of a healthy thoracic aorta. The OpenFOAM solver pimpleFoam was used to simulate blood flow as an incompressible Newtonian fluid, with the aortic walls treated as rigid boundaries. Simulations were conducted for 30 cardiac cycles and ensemble averaging was employed to ensure statistically reliable results.
View Article and Find Full Text PDFJ Clin Med
January 2025
2nd Department of Cardiology, Jagiellonian University Medical College, 31-008 Krakow, Poland.
Myocardial work (MW) is a new echocardiographic parameter used in the assessment of cardiac energy expenditure. The aim of the current study was to evaluate changes in left ventricular MW parameters in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI). One hundred and thirty five consecutive patients who underwent TAVI at one center were evaluated before and after the procedure using transthoracic echocardiography (TTE) to assess the following MW indices: global constructive work (GCW), global wasted work (GWW), global work index (GWI) and global work efficiency (GWE).
View Article and Find Full Text PDFBiomedicines
December 2024
Ludwig Boltzmann Institute for Cardiovascular Research, Center for Biomedical Research and Translational Surgery, Medical University of Vienna, 1090 Vienna, Austria.
Previously, we showed that blood-based polarizing cardioplegia exerted beneficial cardioprotection during hypothermic ischemia; however, these positive effects of blood-based polarizing cardioplegia were reduced during normothermic ischemia compared to blood-based hyperkalemic (depolarizing) cardioplegia. This study compares crystalloid polarizing cardioplegia to crystalloid depolarizing cardioplegia in a normothermic porcine model of cardiopulmonary bypass; Methods: Twelve pigs were randomized to receive either normothermic polarizing ( = 7) or depolarizing ( = 5) crystalloid cardioplegia. After the initiation of cardiopulmonary bypass, normothermic arrest (34 °C, 60 min) was followed by 60 min of on-pump and 90 min of off-pump reperfusion.
View Article and Find Full Text PDFPLoS One
January 2025
CFD Research Corporation, Huntsville, AL, United States of America.
Purpose: To assess physiological metrics during the use of a commercially available bilateral active ankle exoskeleton during a challenging military-relevant task and if use of the exoskeleton during this task influences: metabolic load, physiological measures or rate of perceived exertion.
Methods: Nine healthy volunteers (5M, 4F) completed this randomized cross-over design trial, with a baseline visit and two randomized test sessions (with/without the exoskeleton). Variables included impact on time to exhaustion during walking on a treadmill at varying speeds and gradients (0-15%) at 26.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!