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Cardiac output

Derek Nelson, Rachael M Heuer, Georgina K Cox, John D Stieglitz, Ronald Hoenig, Edward M Mager, Daniel D Benetti, Martin Grosell, Dane A Crossley
Exposure to polycyclic aromatic hydrocarbons (PAH) negatively impacts exercise performance in fish species but the physiological modifications that result in this phenotype are poorly understood. Prior studies have shown that embryonic and juvenile mahi-mahi (Coryphaeus hippurus) exposed to PAH exhibit morphological abnormalities, altered cardiac development and reduced swimming performance. It has been suggested that cardiovascular function inhibited by PAH exposure accounts for the compromised exercise performance in fish species...
October 14, 2016: Aquatic Toxicology
Jacob J Glaser, Cassandra Cardarelli, Samuel Galvagno, Thomas M Scalea, Sarah B Murthi
BACKGROUND: Point-of-care ultrasound often includes cardiac ultrasound. It is commonly used to evaluate cardiac function in critically ill patients but lacks the specific quantitative anatomic assessment afforded by standard transthoracic echocardiography (TTE). We developed the Focused Rapid Echocardiographic Examination (FREE), a hybrid between a cardiac ultrasound and TTE that places an emphasis on cardiac function rather than anatomy. We hypothesized that data obtained from FREE correlate well with TTE while providing actionable information for clinical decision making...
November 2016: Journal of Trauma and Acute Care Surgery
Riccardo Toninato, Silvia Scuri, Vincenzo Tarzia, Gino Gerosa, Francesca M Susin
PURPOSE: The gold standard therapy for patients with advanced heart failure is heart transplant. The gap between donors and patients in waiting lists promoted the development of circulatory support devices, such as the total artificial heart (TAH). Focusing on in vitro tests performed with CardioWest™ TAH (CW) driven by the SynCardia Freedom® portable driver (FD) the present study goals are: i) prove the reliability of a hydraulic circuit used as patient simulator to replicate a quasi-physiological scenario for various hydrodynamic conditions, ii) investigate the hydrodynamic performance of the CW FD, iii) help clinicians in possible interpretation of clinical cases outcomes...
October 15, 2016: International Journal of Artificial Organs
Celine L Bauwens, Derek Toms, Mark Ungrin
Cardiac differentiation of human pluripotent stems cells (hPSCs) is typically carried out in suspension cell aggregates. Conventional aggregate formation of hPSCs involves dissociating cell colonies into smaller clumps, with size control of the clumps crudely controlled by pipetting the cell suspension until the desired clump size is achieved. One of the main challenges of conventional aggregate-based cardiac differentiation of hPSCs is that culture heterogeneity and spatial disorganization lead to variable and inefficient cardiomyocyte yield...
September 25, 2016: Journal of Visualized Experiments: JoVE
Walter H Reinhart
The hematocrit (Hct) determines the oxygen carrying capacity of blood, but also increases blood viscosity and thus flow resistance. From this dual role the concept of an optimum Hct for tissue oxygenation has been derived. Viscometric studies using the ratio Hct/blood viscosity at high shear rate showed an optimum Hct of 50-60% for red blood cell (RBC) suspensions in plasma. For the perfusion of an artificial microvascular network with 5-70μm channels the optimum Hct was 60-70% for high driving pressures. With lower shear rates or driving pressures the optimum Hct shifted towards lower values...
October 21, 2016: Clinical Hemorheology and Microcirculation
C Roehrig, M Govier, J Robinson, A Aneman
BACKGROUND: It remains unclear whether measuring carotid arterial flow by the time velocity integral using vascular Doppler ultrasound can be used to monitor cardiac output and volume responsiveness. METHODS: The carotid Doppler flow (time velocity integral and peak flow velocity variation) was assessed in triplicate by an intensivist with formal vascular ultrasound training. Thirty-three patients admitted following coronary by-pass surgery were studied before and after a passive leg-raising manoeuvre to investigate volume responsiveness (more than 10% increase in cardiac output) along with indices of arterial load measuring cardiac output by thermodilution...
October 21, 2016: Acta Anaesthesiologica Scandinavica
Paul R Territo, Amanda A Riley, Brian P McCarthy, Gary D Hutchins
Recent advancements in PET instrumentation have made the non-invasive assessment of cardiovascular function in small animals a reality. The majority of small animal PET systems use stationary detector gantries, thus affording high temporal resolution imaging of cardiac function. Systems designed to maximize spatial resolution and detection sensitivity employing rotating gantry designs are suboptimal when high temporal resolution imaging is needed. To overcome this limitation, the current work developed a novel view-sharing data analysis scheme suitable for dynamic cardiac PET imaging using (18)F-NaF as the tracer and tracer kinetic model analysis...
December 2016: EJNMMI Physics
Débora Claësson, Tobias Wang, Hans Malte
Global warming results in increasing water temperature, which may represent a threat to aquatic ectotherms. The rising temperature affects ecology through physiology, by exerting a direct limiting effect on the individual. The mechanism controlling individual thermal tolerance is still elusive, but some evidence shows that the heart plays a central role, and that insufficient transport of oxygen to the respiring tissues may determine the thermal tolerance of animals. In this study, the influence of the heart in thermal limitation was investigated by measurements of aerobic scope in the European eel (Anguilla anguilla) together with measurements of cardiac output during rest and activity...
2016: Conservation Physiology
Pavol Sajgalik, Vaclav Kremen, Alex R Carlson, Vratislav Fabian, Chul-Ho Kim, Courtney M Wheatley, Vaclav Gerla, John A Schirger, Thomas P Olson, Bruce D Johnson
Cardiac output (CO) assessment as a basic hemodynamic parameter has been of interest in exercise physiology, cardiology and anesthesiology. Non-invasive techniques available are technically challenging, and thus difficult to use outside of the clinical or laboratory setting. We propose a novel method of non-invasive CO assessment using a single upper arm cuff. The method uses the arterial pressure pulse wave signal acquired from the brachial artery during 20 second intervals of suprasystolic occlusion. This method was evaluated on a cohort of 12 healthy individuals (age of 27...
October 20, 2016: Journal of Applied Physiology
Peter Mathijs van Brussel, Bas van den Bogaard, Barbara A de Weijer, Jasper Truijen, Paul Ct Krediet, Ignace M Janssen, Arnold van de Laar, Karin A Kaasjager, Eric Fliers, Johannes J Van Lieshout, Mireille Johanna Serlie, Bert-Jan H van den Born
BACKGROUND: Blood pressure (BP) decreases in the first weeks after Roux-and-Y gastric bypass surgery. Yet, the pathophysiology of the BP lowering effects observed after gastric bypass surgery are incompletely understood. METHODS: We evaluated BP, systemic hemodynamics and baroreflex sensitivity in 15 obese women (mean age 42±7 yrs, body mass index 45±6 kg/m(2)) two weeks before and six weeks following Roux-and-Y gastric bypass surgery. RESULTS: Six weeks after gastric bypass surgery mean body weight decreased by 13±5 kg (10%, p<0...
October 20, 2016: Journal of Applied Physiology
Matthias Hansen
Advanced hemodynamic monitoring is necessary for adequate management of high-risk patients or patients with derangement of circulation. Studies demonstrate a benefit of early goal directed therapy in unstable cardiopulmonary situations. In these days we have different possibilities of minimally invasive or invasive hemodynamic monitoring. Minimally invasive measurements like pulse conture analysis or pulse wave analysis being less accurate under some circumstances, however only an artery catheter is needed for cardiac output monitoring...
October 2016: Anästhesiologie, Intensivmedizin, Notfallmedizin, Schmerztherapie: AINS
Xianxiu Wan, Jian-Jun Wen, Sue-Jie Koo, Lisa Yi Liang, Nisha Jain Garg
Chronic chagasic cardiomyopathy (CCM) is presented by increased oxidative/inflammatory stress and decreased mitochondrial bioenergetics. SIRT1 senses the redox changes and integrates mitochondrial metabolism and inflammation; and SIRT1 deficiency may be a major determinant in CCM. To test this, C57BL/6 mice were infected with Trypanosoma cruzi (Tc), treated with SIRT1 agonists (resveratrol or SRT1720), and monitored during chronic phase (~150 days post-infection). Resveratrol treatment was partially beneficial in controlling the pathologic processes in Chagas disease...
October 2016: PLoS Pathogens
Kevin Forton, Yoshiki Motoji, Gael Deboeck, Vitalie Faoro, Robert Naeije
There has been revival of in interest in exercise testing of the pulmonary circulation for the diagnosis of pulmonary vascular disease, but there still is uncertainty about body position and the most relevant measurements. Doppler echocardiography pulmonary hemodynamic measurements were performed at progressively increased workload in 26 healthy adult volunteers in supine, semi-recumbent and upright positions which were randomly assigned at 24 hours intervals. Mean pulmonary artery pressure (mPAP) was estimated from the maximum tricuspid regurgitation jet velocity...
October 7, 2016: Journal of Applied Physiology
D Stott, M Bolten, D Paraschiv, I Papastefanou, J B Chambers, N A Kametas
OBJECTIVE: Pregnant hypertensive women who do not respond to labetalol but need vasodilatory therapy for blood pressure (BP) control rapidly progress to severe disease, which may be delayed by early recognition and individualised BP treatment. In this study, we sought to create prediction models at presentation, at 1 and 24 hours after commencement of treatment to identify patients who will not show a sustained response to labetalol and therefore need vasodilatory therapy. METHODS: The study population comprised of 134 women presenting with hypertension at a UK hospital...
October 20, 2016: Ultrasound in Obstetrics & Gynecology
Hsing-Hua Tsai, Chin-Pu Lin, Yi-Hui Lin, Chih-Chin Hsu, Jong-Shyan Wang
PURPOSE: Exercise training improves endothelium-dependent vasodilation, whereas hypoxic stress causes vascular endothelial dysfunction. Monocyte-derived endothelial progenitor cells (Mon-EPCs) contribute to vascular repair process by differentiating into endothelial cells. This study investigates how high-intensity interval (HIT) and moderate-intensity continuous (MCT) exercise training affect circulating Mon-EPC levels and EPC functionality under hypoxic condition. METHODS: Sixty healthy sedentary males were randomized to engage in either HIT (3-min intervals at 40 and 80 % VO2max for five repetitions, n = 20) or MCT (sustained 60 % VO2max, n = 20) for 30 min/day, 5 days/week for 6 weeks, or to a control group (CTL) that did not received exercise intervention (n = 20)...
October 19, 2016: European Journal of Applied Physiology
Taisuke Ishikawa, Yukiomi Tsuji, Naomasa Makita
Bradyarrhythmia is a common heart rhythm abnormality comprising number of diseases and is associated with decreased heart rate due to the failure of action potential generation and propagation at the sinus node. Permanent pacemaker implantation is often used therapeutically to compensate for decreased heart rate and cardiac output. The vast majority of bradyarrhythmia cases are attributable either to aging or to structural abnormalities of the cardiac conduction system, caused by underlying structural heart disease...
October 2016: Journal of Arrhythmia
Marina Pieri, Alessandro Belletti, Fabrizio Monaco, Antonio Pisano, Mario Musu, Veronica Dalessandro, Giacomo Monti, Gabriele Finco, Alberto Zangrillo, Giovanni Landoni
BACKGROUND: In patients undergoing cardiac surgery, a reduced preoperative left ventricular ejection fraction (LVEF) is common and is associated with a worse outcome. Available outcome data for these patients address specific surgical procedures, mainly coronary artery bypass graft (CABG). Aim of our study was to investigate perioperative outcome of surgery on patients with low pre-operative LVEF undergoing a broad range of cardiac surgical procedures. METHODS: Data from patients with pre-operative LVEF ≤40 % undergoing cardiac surgery at a university hospital were reviewed and analyzed...
October 18, 2016: BMC Anesthesiology
Takanori Masuda, Takeshi Nakaura, Yoshinori Funama, Toru Higaki, Masao Kiguchi, Naoyuki Imada, Tomoyasu Sato, Kazuo Awai
OBJECTIVE: We evaluated the effect of the age, sex, total body weight (TBW), height (HT) and cardiac output (CO) of patients on aortic and hepatic contrast enhancement during hepatic-arterial phase (HAP) and portal venous phase (PVP) computed tomography (CT) scanning. METHODS: This prospective study received institutional review board approval; prior informed consent to participate was obtained from all 168 patients. All were examined using our routine protocol; the contrast material was 600 mg/kg iodine...
October 18, 2016: Journal of Computer Assisted Tomography
Shiraz A Maskatia, Rodrigo Ruano, Alireza A Shamshirsaz, Pouya Javadian, Joshua A Kailin, Michael A Belfort, Carolyn A Altman, Nancy A Ayres
INTRODUCTION: Twin-twin transfusion syndrome (TTTS) is the major cause for fetal demise in monochorionic diamniotic pregnancies. Estimated combined cardiac output (CCO) has not been studied in this setting. The primary aims of this study were to compare CCO in twin donor and recipient fetuses and assess differences in CCO before and after laser coagulation therapy. A secondary aim was to evaluate the relationship of CCO with perinatal mortality, defined as intrauterine or neonatal mortality (≤30 days of age) in fetuses that underwent laser coagulation therapy...
October 19, 2016: Echocardiography
Christopher P Lawrance, Matthew C Henn, Jacob R Miller, Michael A Kopek, Andrew J Zhang, Richard B Schuessler, Ralph J Damiano
BACKGROUND: Atrial fibrillation (AF) occurs in 30% of patients with mitral regurgitation referred for surgical intervention. However, the underlying mechanisms in this population are poorly understood. This study examined the effects of acute left atrial volume overload on atrial electrophysiology and the inducibility of AF. METHODS: Ten canines underwent insertion of an atrioventricular shunt between the left ventricle and left atrium. Shunt and aortic flows were calculated, and the shunt was titrated to a shunt fraction to 40% to 50% of cardiac output...
October 15, 2016: Annals of Thoracic Surgery
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