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https://www.readbyqxmd.com/read/28741664/in-vitro-evaluation-of-an-immediate-response-starling-like-controller-for-dual-rotary-blood-pumps
#1
Andrew F Stephens, Michael C Stevens, Shaun D Gregory, Matthias Kleinheyer, Robert F Salamonsen
Rotary ventricular assist devices (VADs) are used to provide mechanical circulatory support. However, their lack of preload sensitivity in constant speed control mode (CSC) may result in ventricular suction or venous congestion. This is particularly true of biventricular support, where the native flow-balancing Starling response of both ventricles is diminished. It is possible to model the Starling response of the ventricles using cardiac output and venous return curves. With this model, we can create a Starling-like physiological controller (SLC) for VADs which can automatically balance cardiac output in the presence of perturbations to the circulation...
July 25, 2017: Artificial Organs
https://www.readbyqxmd.com/read/28738837/assessment-of-cerebral-circulation-in-a-porcine-model-of-intravenously-given-e-coli-induced-fulminant-sepsis
#2
Levente Molnár, Norbert Németh, Mariann Berhés, Endre Hajdú, Lóránd Papp, Ábel Molnár, Judit Szabó, Ádám Deák, Béla Fülesdi
BACKGROUND: The aim of the present work was to assess cerebral hemodynamic changes in a porcine model of E.coli induced fulminant sepsis. METHODS: Nineteen healthy female Hungahib pigs, 10-12 weeks old, randomly assigned into two groups: Control (n = 9) or Septic Group (n = 10). In the Sepsis group Escherichia coli culture suspended in physiological saline was intravenously administrated in a continuously increasing manner according to the following protocol: 2 ml of bacterial culture suspended in physiological saline was injected in the first 30 min, then 4 ml of bacterial culture was administered within 30 min, followed by infusion of 32 ml bacterial culture for 2 h...
July 24, 2017: BMC Anesthesiology
https://www.readbyqxmd.com/read/28738087/exercise-physiology-with-a-left-ventricular-assist-device-analysis-of-heart-pump-interaction-with-a-computational-simulator
#3
Libera Fresiello, Frank Rademakers, Piet Claus, Gianfranco Ferrari, Arianna Di Molfetta, Bart Meyns
Patients with a Ventricular Assist Device (VAD) are hemodynamically stable but show an impaired exercise capacity. Aim of this work is to identify and to describe the limiting factors of exercise physiology with a VAD. We searched for data concerning exercise in heart failure condition and after VAD implantation from the literature. Data were analyzed by using a cardiorespiratory simulator that worked as a collector of inputs coming from different papers. As a preliminary step the simulator was used to reproduce the evolution of hemodynamics from rest to peak exercise (ergometer cycling) in heart failure condition...
2017: PloS One
https://www.readbyqxmd.com/read/28731900/micro-and-macro-circulatory-changes-during-sepsis-and-septic-shock-in-a-rat-model
#4
Tianfeng Hua, Xiaobo Wu, Wei Wang, Hao Li, Jennifer Bradley, Mary Ann Peberdy, Joseph P Ornato, Wanchun Tang
Microcirculation is the motor of sepsis. In the present study, we investigated whether microcirculatory alterations occur prior to changes of systemic hemodynamics in a rat model of cecum ligation and puncture (CLP)-induced sepsis. We further investigated renal microcirculatory changes during sepsis and compared those with buccal microcirculation. Twelve male Sprague-Dawley rats were randomized into a sham control group (n = 6) and a CLP group (n = 6). Perfused microvessel density (PVD) and microvascular flow index (MFI) were evaluated using sidestream dark field (SDF) video microscopy at baseline, 60, 120, 180, 240, 300, and 360 minutes following CLP...
July 20, 2017: Shock
https://www.readbyqxmd.com/read/28730870/cardiac-autonomic-recovery-after-strength-exercise-in-lower-and-upper-limbs
#5
Naerton José Xavier Isidoro, Milana Drumond Ramos Santana, Vitor E Valenti, David M Garner, Luiz Carlos de Abreu
Introduction Strength exercises influence the cardiovascular system by promoting autonomic adjustments induced by the increased metabolic demand and consequent increase in local blood flow. However, it is unclear whether there are differences between upper and lower limbs. We aimedto evaluate recovery of cardiac autonomic modulation afterstrengthexercise in upper and lower limbs. Methods We analysed 29 healthy male subjects physically active but not professional athletes aged between 20 and 35 years old...
July 21, 2017: Acta Cardiologica
https://www.readbyqxmd.com/read/28725206/physiological-signal-analysis-for-evaluating-flow-during-playing-of-computer-games-of-varying-difficulty
#6
Yu Tian, Yulong Bian, Piguo Han, Peng Wang, Fengqiang Gao, Yingmin Chen
Flow is the experience of effortless attention, reduced self-consciousness, and a deep sense of control that typically occurs during the optimal performance of challenging tasks. On the basis of the person-artifact-task model, we selected computer games (tasks) with varying levels of difficulty (difficult, medium, and easy) and shyness (personality) as flow precursors to study the physiological activity of users in a flow state. Cardiac and respiratory activity and mean changes in skin conductance (SC) were measured continuously while the participants (n = 40) played the games...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28724652/correlation-of-admission-heart-rate-with-angiographic-and-clinical-outcomes-in-patients-with-right-coronary-artery-st-segment-elevation-myocardial-infarction-undergoing-primary-percutaneous-coronary-intervention-horizons-ami-the-harmonizing-outcomes-with-revascularization
#7
Ioanna Kosmidou, Thomas McAndrew, Björn Redfors, Monica Embacher, José M Dizon, Roxana Mehran, Ori Ben-Yehuda, Gary S Mintz, Gregg W Stone
BACKGROUND: Bradycardia on presentation is frequently observed in patients with right coronary artery ST-segment elevation myocardial infarction, but it is largely unknown whether it predicts poor angiographic or clinical outcomes in that patient population. We sought to determine the prognostic implications of admission heart rate (AHR) in patients with ST-segment elevation myocardial infarction and a right coronary artery culprit lesion. METHODS AND RESULTS: We analyzed 1460 patients with ST-segment elevation myocardial infarction and a right coronary artery culprit lesion enrolled in the randomized HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial who underwent primary percutaneous coronary intervention...
July 19, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/28724126/comparative-outcomes-after-percutaneous-coronary-intervention-among-black-and-white-patients-treated-at-us-veterans-affairs-hospitals
#8
Taisei Kobayashi, Thomas J Glorioso, Ehrin J Armstrong, Thomas M Maddox, Mary E Plomondon, Gary K Grunwald, Steven M Bradley, Thomas T Tsai, Stephen W Waldo, Sunil V Rao, Subhash Banerjee, Brahmajee K Nallamothu, Deepak L Bhatt, A Garvey Rene, Robert L Wilensky, Peter W Groeneveld, Jay Giri
Importance: Current comparative outcomes among black and white patients treated with percutaneous coronary intervention (PCI) in the Veterans Affairs (VA) health system are not known. Objective: To compare outcomes between black and white patients undergoing PCI in the VA health system. Design, Setting, and Participants: This study compared black and white patients who underwent PCI between October 1, 2007, and September 30, 2013, at 63 VA hospitals using data recorded in the VA Clinical Assessment, Reporting, and Tracking System for Cardiac Catheterization Laboratories (CART-CL) program...
July 19, 2017: JAMA Cardiology
https://www.readbyqxmd.com/read/28721030/regular-physical-exercise-improves-cardiac-autonomic-and-muscle-vasodilatory-responses-to-isometric-exercise-in-healthy-elderly
#9
Adriana de Oliveira Sarmento, Amilton da Cruz Santos, Ivani Credidio Trombetta, Marciano Moacir Dantas, Ana Cristina Oliveira Marques, Leone Severino do Nascimento, Bruno Teixeira Barbosa, Marcelo Rodrigues Dos Santos, Maria do Amparo Andrade, Anna Myrna Jaguaribe-Lima, Maria do Socorro Brasileiro-Santos
The objective of this study was to evaluate cardiac autonomic control and muscle vasodilation response during isometric exercise in sedentary and physically active older adults. Twenty healthy participants, 10 sedentary and 10 physically active older adults, were evaluated and paired by gender, age, and body mass index. Sympathetic and parasympathetic cardiac activity (spectral and symbolic heart rate analysis) and muscle blood flow (venous occlusion plethysmography) were measured for 10 minutes at rest (baseline) and during 3 minutes of isometric handgrip exercise at 30% of the maximum voluntary contraction (sympathetic excitatory maneuver)...
2017: Clinical Interventions in Aging
https://www.readbyqxmd.com/read/28718074/advances-in-imaging-instrumentation-for-nuclear-cardiology
#10
Jae Sung Lee, Gil Kovalski, Tali Sharir, Dong Soo Lee
Advances in imaging instrumentation and technology have greatly contributed to nuclear cardiology. Dedicated cardiac SPECT cameras incorporating novel, highly efficient detector, collimator, and system designs have emerged with the expansion of nuclear cardiology. Solid-state radiation detectors incorporating cadmium zinc telluride, which directly convert radiation to electrical signals and yield improved energy resolution and spatial resolution and enhanced count sensitivity geometries, are increasingly gaining favor as the detector of choice for application in dedicated cardiac SPECT systems...
July 17, 2017: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
https://www.readbyqxmd.com/read/28715078/polish-stress-echocardiography-registry-pol-stress-registry-a-multicenter-study-stress-echo-in-poland-numbers-settings-results-and-complications
#11
Edyta Płońska-Gościniak, Jarosław D Kasprzak, Szymon Olędzki, Jolanta Rzucidło-Resil, Piotr Gościniak, Tomasz Kukulski, Katarzyna Mizia-Stec, Wojciech Kosmala, Dariusz Kosior, Marta Marcinkiewicz-Siemion, Barbara Brzezińska, Beata Zaborska, Marcin Fijałkowski, Iwona Świątkiewicz, Andrzej Szyszka, Jan Błażejewski, Wojciech Witkiewicz, Zbigniew Gąsior, Danuta Sorysz, Agnieszka Olszanecka
BACKGROUND: Stress echocardiography (SE) is widely used in Europe. No collective data have been available on the use of SE in Poland until now. AIM: To evaluate the number of SE investigations performed in Poland, their settings, complications and results. METHODS: In this retrospective survey, referral cardiology centers in Poland were asked to fill in a questionnaire regarding SE examinations performed from May 01, 2014 to May 01, 2015. RESULTS: The study included data from 17 university hospitals and large community hospitals which performed 4611 SE examinations, including 4408 tests in patients investigated for coronary artery disease (CAD) and 203 tests to evaluate valvular heart disease (VHD)...
July 17, 2017: Kardiologia Polska
https://www.readbyqxmd.com/read/28713489/the-inhibitory-effect-of-wenxinkeli-on-h9c2-cardiomyocytes-hypertrophy-induced-by-angiotensin-ii-through-regulating-autophagy-activity
#12
Jie Li, Yang Li, Ying Zhang, Dan Hu, Yonghong Gao, Hongcai Shang, Yanwei Xing
OBJECTIVES: We investigated the role of cardiomyocyte autophagy and its regulatory mechanisms by WenxinKeli (WXKL) in cells subjected to hypertrophy. METHODS: H9C2 cardiomyocytes were divided into 8 groups. Cytoskeletal proteins as well as endogenously expressed autophagy marker proteins were studied by confocal imaging. Western blotting was used to assess the levels of light chain-3 (LC3) and mechanistic target of rapamycin (mTOR). The cell viability assay was used to detect the content of ATP...
2017: Oxidative Medicine and Cellular Longevity
https://www.readbyqxmd.com/read/28711647/surgical-training-improves-performance-in-minimally-invasive-left-ventricular-assist-device-implantation-without-cardiopulmonary-bypass
#13
Lu-Feng Zhang, Hai-Bo Feng, Zhi-Guo Yu, Shi Jing, Feng Wan
OBJECTIVE: We introduced a live animal model for training of minimally invasive implantation of a continuous-flow left ventricular assist device (CF-LVAD) without cardiopulmonary bypass for operator's performance improvement. DESIGN: After watching a videotape of LVAD implantation on the beating heart through the cardiac apex, the surgical team performed implantation of LVADs into 5 pigs during 3 training sessions in a time series. The procedure success rate, operating time, and technical and global performances by self-evaluation and senior evaluation were compared among the sessions...
July 12, 2017: Journal of Surgical Education
https://www.readbyqxmd.com/read/28710899/effects-of-dobutamine-dopamine-phenylephrine-and-noradrenaline-on-systemic-haemodynamics-and-intestinal-perfusion-in-isoflurane-anaesthetised-horses
#14
C Dancker, K Hopster, K Rohn, S B Kästner
BACKGROUND: In the horse, effects of cardiovascular-active drugs on local perfusion of the gastrointestinal tract are poorly understood. OBJECTIVES: To determine the effect of drugs commonly used to support blood pressure, on local intestinal blood flow and tissue oxygenation under isoflurane anaesthesia. STUDY DESIGN: In vivo randomised crossover experiment METHODS: Ten horses were anaesthetised with isoflurane. After 90 minutes of equilibration three doses (μg/kg bwt/min) of dobutamine (DOB 0...
July 15, 2017: Equine Veterinary Journal
https://www.readbyqxmd.com/read/28710067/a-comparison-of-passive-hind-limb-cycling-and-active-upper-limb-exercise-provides-new-insights-into-systolic-dysfunction-following-spinal-cord-injury
#15
Kathryn M DeVeau, Kathryn A Harman, Jordan W Squair, Andrei V Krassioukov, David Magnuson, Christopher R West
BACKGROUND: Active upper-limb and passive lower-limb exercise are two interventions used in the spinal cord injury (SCI) population. While the global cardiac responses have been previously studied, it is unclear how either exercise influences contractile cardiac function. Here, the cardiac contractile and volumetric responses to upper-limb (swim) and passive lower-limb exercise are investigated in rodents with a severe high-thoracic SCI. METHODS: Animals were divided into a control (CON), SCI no exercise (NO-EX), SCI passive hind-limb cycling (PHLC) or SCI swim (SWIM) group...
July 14, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28708664/esmolol-administration-to-control-tachycardia-in-an-ovine-model-of-peritonitis
#16
Koji Hosokawa, Fuhong Su, Fabio Silvio Taccone, Emiel Hendrik Post, Adriano José Pereira, Antoine Herpain, Jacques Creteur, Jean-Louis Vincent
BACKGROUND: Excessive adrenergic signaling may be harmful in sepsis. Using β-blockers to reduce sympathetic overactivity may modulate sepsis-induced cardiovascular, metabolic, immunologic, and coagulation alterations. Using a randomized ovine fecal peritonitis model, we investigated whether administration of a short-acting β-blocker, esmolol, could control tachycardia without deleterious effects on hemodynamics, renal perfusion, cerebral perfusion, cerebral metabolism, or outcome. METHODS: After induction of fecal peritonitis, 14 anesthetized, mechanically ventilated, and hemodynamically monitored adult female sheep were randomly assigned to receive a continuous intravenous infusion of esmolol to control heart rate between 80 and 100 bpm (n = 7) or a saline infusion (control group, n = 7)...
July 13, 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/28708210/particle-image-velocimetry-tests-on-pediatric-45-cc-and-30-cc-ventricle-assist-devices-effects-of-heart-rate-on-vad-operation
#17
Dariusz Witkowski, Damian Obidowski, Piotr Reorowicz, Daniel Jodko, Krzysztof Jozwik
BACKGROUND: This study investigated flow analysis inside pediatric ventricle assist devices (VADs) designed and manufactured at the Foundation for Cardiac Surgery Development (FRK), Zabrze, Poland. The main goal of the experiment was to define the minimal heart rate admissible in clinical practice. METHODS: The flow was directed by mechanical, single-disc valves developed at the Lodz University of Technology, Institute of Turbomachinery in Lodz, Poland. VAD operation conditions under different heart rates were analyzed...
July 8, 2017: International Journal of Artificial Organs
https://www.readbyqxmd.com/read/28706270/comprehensive-multi-dimensional-mri-for-the-simultaneous-assessment-of-cardiopulmonary-anatomy-and-physiology
#18
Joseph Y Cheng, Tao Zhang, Marcus T Alley, Martin Uecker, Michael Lustig, John M Pauly, Shreyas S Vasanawala
Diagnostic testing often assesses the cardiovascular or respiratory systems in isolation, ignoring the major pathophysiologic interactions between the systems in many diseases. When both systems are assessed currently, multiple modalities are utilized in costly fashion with burdensome logistics and decreased accessibility. Thus, we have developed a new acquisition and reconstruction paradigm using the flexibility of MRI to enable a comprehensive exam from a single 5-15 min scan. We constructed a compressive-sensing approach to pseudo-randomly acquire highly subsampled, multi-dimensionally-encoded and time-stamped data from which we reconstruct volumetric cardiac and respiratory motion phases, contrast-agent dynamics, and blood flow velocity fields...
July 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28703280/the-oregonheart-total-artificial-heart-design-and-performance-on-a-mock-circulatory-loop
#19
Jeremy Glynn, Howard Song, Bryan Hull, Stanley Withers, Jill Gelow, James Mudd, Albert Starr, Richard Wampler
Widespread use of heart transplantation is limited by the scarcity of donor organs. Total artificial heart (TAH) development has been pursued to address this shortage, especially to treat patients who require biventricular support. We have developed a novel TAH that utilizes a continuously spinning rotor that shuttles between two positions to provide pulsatile, alternating blood flow to the systemic and pulmonary circulations without artificial valves. Flow rates and pressures generated by the TAH are controlled by adjusting rotor speed, cycle frequency, and the proportion of each cycle spent pumping to either circulation...
July 13, 2017: Artificial Organs
https://www.readbyqxmd.com/read/28699088/sepsis-prediction-in-critically-ill-patients-by-platelet-activation-markers-on-icu-admission-a-prospective-pilot-study
#20
Nathalie Layios, Céline Delierneux, Alexandre Hego, Justine Huart, Christian Gosset, Christelle Lecut, Nathalie Maes, Pierre Geurts, Arnaud Joly, Patrizio Lancellotti, Adelin Albert, Pierre Damas, André Gothot, Cécile Oury
BACKGROUND: Platelets have been involved in both immune surveillance and host defense against severe infection. To date, whether platelet phenotype or other hemostasis components could be associated with predisposition to sepsis in critical illness remains unknown. The aim of this work was to identify platelet markers that could predict sepsis occurrence in critically ill injured patients. METHODS: This single-center, prospective, observational, 7-month study was based on a cohort of 99 non-infected adult patients admitted to ICUs for elective cardiac surgery, trauma, acute brain injury, and post-operative prolonged ventilation and followed up during ICU stay...
December 2017: Intensive Care Medicine Experimental
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