keyword
MENU ▼
Read by QxMD icon Read
search

Bradycardic

keyword
https://www.readbyqxmd.com/read/28964689/exercise-training-improves-hypertension-induced-autonomic-dysfunction-without-influencing-properties-of-peripheral-cardiac-vagus-nerve
#1
Octávio Barbosa Neto, Carla Cristina de Sordi, Gustavo Ribeiro da Mota, Moacir Marocolo, Rosângela Soares Chriguer, Valdo José Dias da Silva
We examined the vagal transfer function of autonomic heart rate (HR) control in anesthetized sedentary and exercise-trained Spontaneously Hypertensive Rats (SHR). To this end, male SHR and Wystar-Kyoto (WKY) rats with 48-50weeks of age-old were divided into 4 groups: sedentary (SHRS, n=12) and trained (SHRT, n=14) hypertensive rats, sedentary (WKYS, n=13) and trained (WKYT, n=13) normotensive rats. The trained groups were submitted to swimming protocol for 9weeks. Blood pressure (BP), HR, HR variability (HRV), BP variability (BPV), baroreflex sensitivity and cardiac tonus were recorded in baseline conditions...
September 14, 2017: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/28923167/cyclic-bouts-of-extreme-bradycardia-counteract-the-high-metabolism-of-frugivorous-bats
#2
M Teague O'Mara, Martin Wikelski, Christian C Voigt, Andries Ter Maat, Henry S Pollock, Gary Burness, Lanna M Desantis, Dina Kn Dechmann
Active flight requires the ability to efficiently fuel bursts of costly locomotion while maximizing energy conservation during non-flying times. We took a multi-faceted approach to estimate how fruit-eating bats (Uroderma bilobatum) manage a high-energy lifestyle fueled primarily by fig juice. Miniaturized heart rate telemetry shows that they use a novel, cyclic, bradycardic state that reduces daily energetic expenditure by 10% and counteracts heart rates as high as 900 bpm during flight. Uroderma bilobatum support flight with some of the fastest metabolic incorporation rates and dynamic circulating cortisol in vertebrates...
September 19, 2017: ELife
https://www.readbyqxmd.com/read/28893930/how-human-amygdala-and-bed-nucleus-of-the-stria-terminalis-may-drive-distinct-defensive-responses
#3
Floris Klumpers, Marijn C W Kroes, Johanna M P Baas, Guillén Fernández
The ability to adaptively regulate responses to the proximity of potential danger is critical to survival and imbalance in this system may contribute to psychopathology. The bed nucleus of the stria terminalis (BNST) is implicated in defensive responding during uncertain threat anticipation whereas the amygdala may drive responding upon more acute danger. This functional dissociation between the BNST and amygdala is however controversial, and human evidence scarce. Here we used data from two independent functional magnetic resonance imaging studies [n = 108 males and n = 70 (45 females)] to probe how coordination between the BNST and amygdala may regulate responses during shock anticipation and actual shock confrontation...
October 4, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28877873/the-in-vitro-zebrafish-heart-as-a-model-to-investigate-the-chronotropic-effects-of-vapor-anesthetics
#4
Matthew R Stoyek, Michael K Schmidt, Florentin M Wilfart, Roger P Croll, Frank M Smith
In addition to their intended clinical actions, all general anesthetic agents in common use have detrimental intra- and post-surgical side effects on organs and systems including the heart. The major cardiac side effect of anesthesia is bradycardia, which increases the probability of insufficient systemic perfusion during surgery. These side effects also occur in all vertebrate species so far examined, but the underlying mechanisms are not clear. The zebrafish heart is a powerful model for studying cardiac electrophysiology, employing the same pacemaker system and neural control as do mammalian hearts...
September 6, 2017: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/28845312/symptomatic-long-pauses-and-bradycardia-due-to-massive-multinodular-goiter
#5
Amrish Deshmukh, Cevher Ozcan
Sinus node dysfunction with symptomatic bradycardia or chronotropic incompetence is generally an indication for pacemaker implantation. However, in patients with symptomatic sinus bradycardia, the identification and treatment of underlying pathologies may avoid the need for permanent pacemaker implantation. We present a case of carotid sinus syndrome and severe obstructive sleep apnea due to a massive multinodular goiter in a patient who presented with recurrent sinus pauses and syncope. The patient was managed without pacemaker implantation but instead with thyroidectomy resulting in decompression of the carotid sinus and airway and resolution of bradycardic episodes...
2017: Case Reports in Cardiology
https://www.readbyqxmd.com/read/28798240/tetraparesia-an-unusual-presentation-of-disseminated-tuberculosis
#6
Filipa Quaresma, Margarida Bentes Jesus
A 48-year-old man with a 4 months history of asthenia, anorexia, 10 kg weight loss and 1 month of hematuria and dysuria was admitted to another hospital for sudden muscular weakness. He was found to have areflexic tetraparesis and was referred to our hospital.On admission, he was bradycardic, tachypneic, with flaccid tetraplegia. Laboratory results showed metabolic acidemia, severe hyperkalemia and hyponatremia, acute renal dysfunction and sterile pyuria. After hyperkalemia correction, the neurological symptoms resolved...
August 10, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28747364/cerebral-oxygenation-during-skin-to-skin-care-in-preterm-infants-not-receiving-respiratory-support
#7
Laila Lorenz, Adriana Marulli, Jennifer A Dawson, Louise S Owen, Brett J Manley, Susan M Donath, Peter G Davis, C Omar F Kamlin
OBJECTIVE: Skin-to-skin care (SSC) has proven benefits in preterm infants, but increased hypoxic and bradycardic events have been reported. This may make clinicians hesitant to recommend SSC as standard care. We hypothesised that regional cerebral oxygenation (rStO2) measured with near infrared spectroscopy is not worse during SSC compared with standard incubator care. DESIGN: Prospective, observational, non-inferiority study. SETTING: Single tertiary perinatal centre in Australia...
July 26, 2017: Archives of Disease in Childhood. Fetal and Neonatal Edition
https://www.readbyqxmd.com/read/28738010/effects-of-the-%C3%AE-2-adrenoceptor-agonist-medetomidine-on-the-distribution-and-clearance-of-alfaxalone-during-coadministration-by-constant-rate-infusion-in-dogs
#8
Rachel C Bennett, Kati M Salla, Marja R Raekallio, Mika Scheinin, Outi M Vainio
OBJECTIVE To assess the possible impact of medetomidine on concentrations of alfaxalone in plasma, when coadministered as a constant rate infusion (CRI) to dogs, and to determine the possible impact of medetomidine on the cardiopulmonary effects of alfaxalone during CRI. ANIMALS 8 healthy adult Beagles. PROCEDURES 3 treatments were administered in a randomized crossover design as follows: 1 = saline (0.9% NaCl) solution injection, followed in 10 minutes by induction of anesthesia with alfaxalone (loading dose, 2...
August 2017: American Journal of Veterinary Research
https://www.readbyqxmd.com/read/28710197/cervical-shock-a-complication-of-incomplete-abortion
#9
Julian David Birch, Divyansh Gulati, Sachin Mandalia
A case of a 37-year-old female primagravida who attended the emergency department (ED) via ambulance in hypotensive shock. She was 10 weeks pregnant, but had an inevitable miscarriage confirmed in the local Early Pregnancy Unit 3 weeks previously. She was hypotension (90/60 mm Hg), bradycardic (45 bpm) and was peripherally shut down. A provisional diagnosis of haemorrhagic shock was made, but despite intravenous fluid challenges, she appeared to be deteriorating, so a major haemorrhage protocol was activated...
July 14, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28690942/cardiac-arrhythmias-resulting-from-a-peripherally-inserted-central-catheter-two-cases-and-a-review-of-the-literature
#10
Jonathan Gapp, Mridula Krishnan, Felicia Ratnaraj, Robert P Schroell, Douglas Moore
We present two cases of patients being treated for diabetic ketoacidosis in the intensive care unit who experienced cardiac arrhythmia secondary to peripherally inserted central catheters (PICCs). In one instance, the patient became bradycardic and experienced related loss of consciousness, ultimately requiring cardiopulmonary resuscitation. In the second case, the patient experienced an episode of nonsustained ventricular tachycardia. We explore the various types of arrhythmias that have been reported secondary to central venous catheters, as well as factors that place patients at an increased risk for arrhythmia while undergoing PICC insertion...
June 3, 2017: Curēus
https://www.readbyqxmd.com/read/28677303/glial-eaat2-regulation-of-extracellular-nts-glutamate-critically-controls-neuronal-activity-and-cardiorespiratory-reflexes
#11
Michael P Matott, David D Kline, Eileen M Hasser
KEY POINTS: Excitatory amino acid transporter 2 (EAAT2) is present on astrocytes in the nucleus tractus solitarii (nTS), an important nucleus in cardiorespiratory control. Its specific role in influencing nTS neuronal activity and thereby basal and reflex cardiorespiratory function is unknown. The specific role of nTS EAAT2 was determined via whole animal and brainstem slice patch clamp experiments. Astrocytic EAAT2 buffers basal glutamate activation of AMPA-type glutamate receptors and therefore decreases baseline excitability of nTS neurons...
September 1, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28635325/effect-of-salt-loading-on-baroreflex-sensitivity-in-reduced-renal-mass-hypertension
#12
Besim Özaykan, Eylem Taskin, Ali Magemizoğlu
BACKGROUND: High dietary salt, as well as renal mass reduction, is known to decrease baroreflex sensitivity in rats. However, the effect of high salt intake on baroreflex sensitivity is unknown in reduced renal mass (RRM) hypertension; therefore, the aim of this study was to investigate the effects of salt loading on arterial baroreflex sensitivity and mean arterial pressure (MAP) in RRM hypertension. METHODS: Both RRM and sham-operated control (SO) rats were loaded with 0...
June 21, 2017: Clinical and Experimental Hypertension: CHE
https://www.readbyqxmd.com/read/28624975/deleterious-acute-and-chronic-effects-of-bradycardic-right-ventricular-apex-pacing-consequences-for-arrhythmic-outcome
#13
T R G Stams, A Dunnink, W M van Everdingen, H D M Beekman, R van der Nagel, B Kok, M F A Bierhuizen, M J Cramer, M Meine, M A Vos
In the chronic complete atrioventricular (AV) block dog (CAVB) model, both bradycardia and altered ventricular activation due to the uncontrolled idioventricular rhythm contribute to ventricular remodeling and the enhanced susceptibility to Torsade de Pointes (TdP) arrhythmias. We investigated the effect of permanent bradycardic right ventricular apex (RVA) pacing on mechanical and electrical remodeling and TdP. In 23 anesthetized dogs, serial experiments were performed at sinus rhythm (SR), acutely after AV block (AAVB) and 3 weeks of remodeling CAVB at a fixed pacing rate of 60/min...
July 2017: Basic Research in Cardiology
https://www.readbyqxmd.com/read/28615326/prenatal-nicotinic-exposure-prolongs-superior-laryngeal-c-fiber-mediated-apnea-and-bradycardia-through-enhancing-neuronal-trpv1-expression-and-excitation
#14
Xiuping Gao, Lei Zhao, Jianguo Zhuang, Na Zang, Fadi Xu
Maternal cigarette smoke, including prenatal nicotinic exposure (PNE), is responsible for sudden infant death syndrome (SIDS). The fatal events of SIDS are characterized by severe bradycardia and life-threatening apneas. Although activation of transient receptor potential vanilloid 1 (TRPV1) of superior laryngeal C-fibers (SLCFs) could induce bradycardia and apnea and has been implicated in SIDS pathogenesis, how PNE affects the SLCF-mediated cardiorespiratory responses remains unexplored. Here, we tested the hypothesis that PNE would aggravate the SLCF-mediated apnea and bradycardia via up-regulating TRPV1 expression and excitation of laryngeal C-neurons in the nodose/jugular (N/J) ganglia...
June 14, 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
https://www.readbyqxmd.com/read/28612303/additive-proarrhythmic-effect-of-combined-treatment-with-qt-prolonging-agents
#15
Gerrit Frommeyer, Christina Fischer, Christian Ellermann, Dirk G Dechering, Simon Kochhäuser, Philipp S Lange, Kristina Wasmer, Michael Fehr, Lars Eckardt
Drug combinations may elevate the risk of proarrhythmia. The aim of the present study was to investigate whether combinations of non-cardiovascular agents induce an additive increase in the proarrhythmic risk. In 12 female rabbit hearts, a drug combination of cotrimoxazole (300 µM), ondansetron (5 µM) and domperidone (1 µM) was infused after obtaining baseline data. In another 13 hearts, a combination of cotrimoxazole (300 µM), ondansetron (5 µM) and erythromycin (300 µM) was infused. Monophasic action potentials and ECG displayed a significant QT prolongation in all groups...
June 13, 2017: Cardiovascular Toxicology
https://www.readbyqxmd.com/read/28606656/divergent-antiarrhythmic-effects-of-resveratrol-and-piceatannol-in-a-whole-heart-model-of-long-qt-syndrome
#16
Christian Ellermann, Julian Wolfes, Simon Kochhäuser, Dirk G Dechering, Florian Reinke, Kristina Wasmer, Lars Eckardt, Gerrit Frommeyer
BACKGROUND: The polyphenol resveratrol and its metabolite piceatannol have beneficial health effects including antiarrhythmic properties in ischemia/reperfusion. The objective of this study was to determine potential antiarrhythmic effects in acquired long-QT-syndrome (LQTS). METHODS AND RESULTS: 26 rabbit hearts were isolated and Langendorff-perfused. The IKr-blocker sotalol (100μM) was infused to mimic LQTS-2. Hearts were assigned to two groups. Sotalol significantly prolonged action potential duration (APD90) and QT-interval in both groups (group 1:APD90: +18ms, p<0...
September 15, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/28587528/a-prospective-observational-cohort-study-of-exposure-to-womb-like-sounds-to-stabilize-breathing-and-cardiovascular-patterns-in-preterm-neonates
#17
Joanna J Parga, Ravi R Bhatt, Kalpashri Kesavan, Myung-Shin Sim, Harvey N Karp, Ronald M Harper, Lonnie Zeltzer
PURPOSE: We exposed premature infants to womb-like sounds to evaluate such exposure on breathing and cardiovascular patterns. We hypothesized that these sounds would reduce apnea and intermittent hypoxemia, enhance parasympathetic outflow, and improve cardiovascular patterns. METHODS: A total of 20 cases and 5 control infants at ≤32-36 weeks corrected gestational age participated in a prospective observational cohort study. Twenty-four hours of continuous ECG, respiratory and oxygen saturation data were collected in all infants...
June 22, 2017: Journal of Maternal-fetal & Neonatal Medicine
https://www.readbyqxmd.com/read/28576724/interaction-of-gaba-and-norepinephrine-in-the-lateral-division-of-the-bed-nucleus-of-the-stria-terminals-in-anesthetized-rat-correlating-single-unit-and-cardiovascular-responses
#18
Fahimeh Yeganeh, Ali Nasimi, Masoumeh Hatam
The bed nucleus of the stria terminalis (BST) consists of multiple anatomically distinct nuclei. The lateral division, which receives dense noradrenergic innervation, has been implicated in cardiovascular regulation and modulation of responses to stress. This study is performed to identify the cardiovascular and single-unit responses of the lateral BST to norepinephrine (NE), involved adrenoceptors, and possible interaction with GABAergic system of the BST in urethane-anesthetized rats. NE, adrenoreceptor antagonists, and GABAA antagonist were microinjected into the lateral division of BST, while arterial pressure (AP), heart rate (HR), and single-unit responses were simultaneously recorded...
May 31, 2017: Neuroscience
https://www.readbyqxmd.com/read/28562833/the-effect-of-physical-resistance-training-on-baroreflex-sensitivity-of-hypertensive-rats
#19
Moisés Felipe Pereira Gomes, Mariana Eiras Borges, Vitor de Almeida Rossi, Elizabeth de Orleans C de Moura, Alessandra Medeiros
Background: Baroreceptors act as regulators of blood pressure (BP); however, its sensitivity is impaired in hypertensive patients. Among the recommendations for BP reduction, exercise training has become an important adjuvant therapy in this population. However, there are many doubts about the effects of resistance exercise training in this population. Objective: To evaluate the effect of resistance exercise training on BP and baroreceptor sensitivity in spontaneously hypertensive rats (SHR)...
2017: Arquivos Brasileiros de Cardiologia
https://www.readbyqxmd.com/read/28547743/the-anaesthetized-rabbit-with-acute-atrioventricular-block-provides-a-new-model-for-detecting-drug-induced-torsade-de-pointes
#20
Mihoko Hagiwara, Seiji Shibuta, Kazuhiro Takada, Ryuichi Kambayashi, Misako Nakajo, Megumi Aimoto, Yoshinobu Nagasawa, Akira Takahara
BACKGROUND AND PURPOSE: Several rabbit proarrhythmia models have been developed using genetic or pharmacological methods to suppress the slow component of delayed rectifier K(+) currents in the ventricle, leading to reduction of the repolarization reserve. Here we have characterized a novel rabbit in vivo proarrhythmia model with severe bradycardia caused by acute atrioventricular block (AVB). EXPERIMENTAL APPROACH: Bradycardia was induced in isoflurane-anaesthetized rabbits by inducing AVB with catheter ablation, and the ventricle was electrically driven at 60 beats min(-1) throughout the experiment except when extrasystoles appeared...
August 2017: British Journal of Pharmacology
keyword
keyword
89783
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"