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ECG Challenge Response

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https://www.readbyqxmd.com/read/27909532/ajmaline-challenge-to-unmask-infrahisian-disease-in-patients-with-recurrent-and-unexplained-syncope-preserved-ejection-fraction-with-or-without-conduction-abnormalities-on-surface-ecg
#1
Francesco Pentimalli, Luca Bacino, Matteo Ghione, Giambattista Siri, Massimo Gazzarata, Paolo Bellotti
Background: Pharmacological challenge with class I antiarrhythmic drug is a recommended diagnostic test in patients with unexplained syncope only in the presence of bundle branch block, when non-invasive tests have failed to make the diagnosis. Its role in patients with minor or no conduction disturbances on 12-leads ECG has not been evaluated yet. It is also not clear which are the values of His-Ventricular interval to be considered diagnostic. We sought to evaluate the role of ajmaline challenge in unmasking the presence of an infrahisian disease in patients with recurrent and unexplained syncope, regardless of the existence of conduction disturbances on surface ECG...
August 2016: Journal of Atrial Fibrillation
https://www.readbyqxmd.com/read/27803673/electrophysiological-mechanisms-of-brugada-syndrome-insights-from-pre-clinical-and-clinical-studies
#2
REVIEW
Gary Tse, Tong Liu, Ka H C Li, Victoria Laxton, Yin W F Chan, Wendy Keung, Ronald A Li, Bryan P Yan
Brugada syndrome (BrS), is a primary electrical disorder predisposing affected individuals to sudden cardiac death via the development of ventricular tachycardia and fibrillation (VT/VF). Originally, BrS was linked to mutations in the SCN5A, which encodes for the cardiac Na(+) channel. To date, variants in 19 genes have been implicated in this condition, with 11, 5, 3, and 1 genes affecting the Na(+), K(+), Ca(2+), and funny currents, respectively. Diagnosis of BrS is based on ECG criteria of coved- or saddle-shaped ST segment elevation and/or T-wave inversion with or without drug challenge...
2016: Frontiers in Physiology
https://www.readbyqxmd.com/read/27761167/genetics-of-brugada-syndrome
#3
Jyh-Ming Jimmy Juang, Minoru Horie
In 1992, the Brugada syndrome (BrS) was recognized as a disease responsible for sudden cardiac death, characterized by a right bundle-branch block with ST segment elevation in the leads V1 and V2. This syndrome is highly associated with sudden cardiac death, especially in young males. BrS is currently diagnosed in patients with ST-segment elevation showing type 1 morphology ≥ 2 mm in ≥1 leads among the right precordial leads V1 or V2 positioned in the 2nd, 3rd, or 4th intercostal space, and occurring either spontaneously or after a provocative drug test by the intravenous administration of Class I antiarrhythmic drugs...
October 2016: Journal of Arrhythmia
https://www.readbyqxmd.com/read/27733384/interactive-effects-of-maternal-cigarette-smoke-heat-stress-hypoxia-and-lipopolysaccharide-on-neonatal-cardiorespiratory-and-cytokine-responses
#4
Fiona B McDonald, Kumaran Chandrasekharan, Richard J A Wilson, Shabih U Hasan
Maternal cigarette smoke (CS) exposure exhibits a strong epidemiological association with Sudden Infant Death Syndrome, but other environmental stressors, including infection, hyperthermia, and hypoxia, have also been postulated as important risk factors. This study examines whether maternal CS exposure causes maladaptations within homeostatic control networks by influencing the response to lipopolysaccharide, heat stress, and/or hypoxia in neonatal rats. Pregnant dams were exposed to CS or parallel sham treatments daily for the length of gestation...
December 1, 2016: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/27626806/optimizing-estimates-of-instantaneous-heart-rate-from-pulse-wave-signals-with-the-synchrosqueezing-transform
#5
Hau-Tieng Wu, Gregory F Lewis, Maria I Davila, Ingrid Daubechies, Stephen W Porges
BACKGROUND: With recent advances in sensor and computer technologies, the ability to monitor peripheral pulse activity is no longer limited to the laboratory and clinic. Now inexpensive sensors, which interface with smartphones or other computer-based devices, are expanding into the consumer market. When appropriate algorithms are applied, these new technologies enable ambulatory monitoring of dynamic physiological responses outside the clinic in a variety of applications including monitoring fatigue, health, workload, fitness, and rehabilitation...
October 17, 2016: Methods of Information in Medicine
https://www.readbyqxmd.com/read/27474416/reduced-npy-y1-receptor-hippocampal-expression-and-signs-of-decreased-vagal-modulation-of-heart-rate-in-mice
#6
Rosario Statello, Luca Carnevali, Silvia Paterlini, Laura Gioiosa, Ilaria Bertocchi, Alessandra Oberto, Carola Eva, Paola Palanza, Andrea Sgoifo
Central neuropeptide Y (NPY) signaling participates in the regulation of cardiac autonomic outflow, particularly via activation of NPY-Y1 receptors (Y1Rs). However, the specific brain areas and neural pathways involved have not been completely identified yet. Here, we evaluate the role of hippocampal Y1Rs in the modulation of the autonomic control of cardiac function using a conditional knockout mouse model. Radiotelemetric transmitters were implanted in 4-month-old male mice exhibiting reduced forebrain expression (rfb) of the Y1R (Npy1r(rfb), n=10) and their corresponding controls (Npy1r(2lox), n=8)...
July 26, 2016: Physiology & Behavior
https://www.readbyqxmd.com/read/27452149/-depressive-symptoms-during-anorexia-nervosa-state-of-the-art-and-consequences-for-an-appropriate-use-of-antidepressants
#7
N Leblé, L Radon, M Rabot, N Godart
OBJECTIVE: Depressive comorbidity is often associated with anorexia nervosa (AN), and antidepressant medication is widely used although it does not rely on any convincing data in the scientific literature. Our objectives were: to summarize the epidemiological, physiological, psychopathological literature about the relation between AN and manifestations of depression, and to focus on the clinical trial data assessing the use of antidepressant medication in AN in order to clarify the strategy for the use of antidepressant in AN during adolescence...
July 21, 2016: L'Encéphale
https://www.readbyqxmd.com/read/27418320/why-cardiovascular-screening-in-young-athletes-can-save-lives-a-critical-review
#8
Jonathan A Drezner, Kimberly G Harmon, Irfan M Asif, Joseph C Marek
Cardiovascular (CV) screening in young athletes remains challenging and a topic of considerable debate. Recent criticisms of ECG screening have perpetuated arguments that ECG screening is neither indicated nor effective by applying outdated incidence data and flawed methodology. In response, this article provides a critical review of the arguments in favour of ECG screening in athletes and the early detection of CV disorders at elevated risk of sudden cardiac death (SCD). Importantly, no study to date has demonstrated that screening by history and physical examination alone is effective in detecting athletes at risk or in preventing SCD...
November 2016: British Journal of Sports Medicine
https://www.readbyqxmd.com/read/27265056/application-of-the-relative-wavelet-energy-to-heart-rate-independent-detection-of-atrial-fibrillation
#9
Manuel García, Juan Ródenas, Raúl Alcaraz, José J Rieta
BACKGROUND AND OBJECTIVES: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a growing healthcare burden worldwide. It is often asymptomatic and may appear as episodes of very short duration; hence, the development of methods for its automatic detection is a challenging requirement to achieve early diagnosis and treatment strategies. The present work introduces a novel method exploiting the relative wavelet energy (RWE) to automatically detect AF episodes of a wide variety in length...
July 2016: Computer Methods and Programs in Biomedicine
https://www.readbyqxmd.com/read/27222313/inhibition-of-rac1-reduces-store-overload-induced-calcium-release-and-protects-against-ventricular-arrhythmia
#10
Lili Zhang, Xiangru Lu, Le Gui, Yan Wu, Stephen M Sims, Guoping Wang, Qingping Feng
Rac1 is a small GTPase and plays key roles in multiple cellular processes including the production of reactive oxygen species (ROS). However, whether Rac1 activation during myocardial ischaemia and reperfusion (I/R) contributes to arrhythmogenesis is not fully understood. We aimed to study the effects of Rac1 inhibition on store overload-induced Ca(2+) release (SOICR) and ventricular arrhythmia during myocardial I/R. Adult Rac1(f/f) and cardiac-specific Rac1 knockdown (Rac1(ckd) ) mice were subjected to myocardial I/R and their electrocardiograms (ECGs) were monitored for ventricular arrhythmia...
August 2016: Journal of Cellular and Molecular Medicine
https://www.readbyqxmd.com/read/26921481/comparing-maximum-autonomic-activity-of-psychogenic-non-epileptic-seizures-and-epileptic-seizures-using-heart-rate-variability
#11
Jesper Jeppesen, Sándor Beniczky, Peter Johansen, Per Sidenius, Anders Fuglsang-Frederiksen
PURPOSE: The semiology of psychogenic non-epileptic seizures (PNES) can resemble epileptic seizures, and differentiation between epileptic seizures with no EEG-correlate and PNES can be challenging even for trained experts. Therefore, there has been a search for a quantitative measure, other than EEG and semiology that could distinguish PNES from epileptic seizures. We used ECG to measure heart rate variability (HRV) in order to compare maximum autonomic activity of epileptic seizures and PNES...
April 2016: Seizure: the Journal of the British Epilepsy Association
https://www.readbyqxmd.com/read/26883243/effect-of-hypovolemia-on-efficacy-of-reflex-maintenance-of-blood-pressure-on-orthostatic-challenge
#12
Kavita Yadav, Akanksha, Ashok Kumar Jaryal, Poonam Coshic, Kabita Chatterjee, K K Deepak
INTRODUCTION: Blood volume is an important determinant of the efficacy of the negative feedback mechanisms that maintain blood pressure. However, its effect on time profile and magnitude of the responses remain unstudied. AIM: To study the effect of mild hypovolemia on time profiles and magnitude of changes in blood pressure and heart rate in healthy subjects before and after blood donation. METHODS: Fifty six healthy volunteer donors who signed up for blood donation were recruited (age 35 ± 7 years; weight 75 ± 9 Kg)...
March 2016: High Blood Pressure & Cardiovascular Prevention: the Official Journal of the Italian Society of Hypertension
https://www.readbyqxmd.com/read/26796558/-psychiatrists-decision-making-and-monitoring-of-antipsychotic-prescription-for-elderly-schizophrenia-patients
#13
I Jalenques, V Ortega, G Legrand, C Auclair
OBJECTIVE: Advancing age entails specific treatment modalities for patients with schizophrenia. The choice of appropriate antipsychotic therapy (AP) and the monitoring of treatment is a major challenge. However, little is known about the real-world prescribing practices of psychiatrists for elderly schizophrenia patients. The aim of this study was to assess prescribing practices and treatment monitoring in elderly schizophrenia patients and whether socio-professional psychiatrists' characteristics are related to their practices...
April 2016: L'Encéphale
https://www.readbyqxmd.com/read/26737699/autonomic-nervous-system-response-to-l-dopa-in-patients-with-advanced-parkinson-s-disease
#14
Verneri Ruonala, Mika P Tarvainen, Pasi A Karjalainen, Eero Pekkonen, Saara M Rissanen
Levodopa is the main treatment method for reducing the symptoms of Parkinson's disease. Whereas it reduces the motor symptoms efficiently, its effect on autonomous nervous system is not clear. The information about effect of levodopa on heart rate variability is not coherent between the studies. In this study, ECG of 11 patients with Parkinson's disease was measured during levodopa challenge with pronounced dose of fast release levodopa to ensure the positive drug effect for deep brain stimulation treatment...
2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/26597978/coronary-endothelial-function-assessment-using-self-gated-cardiac-cine-mri-and-k-t-sparse-sense
#15
Jérôme Yerly, Giulia Ginami, Giovanna Nordio, Andrew J Coristine, Simone Coppo, Pierre Monney, Matthias Stuber
PURPOSE: Electrocardiogram (ECG)-gated cine MRI, paired with isometric handgrip exercise, can be used to accurately, reproducibly, and noninvasively measure coronary endothelial function (CEF). Obtaining a reliable ECG signal at higher field strengths, however, can be challenging due to rapid gradient switching and an increased heart rate under stress. To address these limitations, we present a self-gated cardiac cine MRI framework for CEF measurements that operates without ECG signal...
November 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/26529426/effective-emotion-regulation-strategies-improve-fmri-and-ecg-markers-of-psychopathology-in-panic-disorder-implications-for-psychological-treatment-action
#16
A Reinecke, N Filippini, C Berna, D G Western, B Hanson, M J Cooper, P Taggart, C J Harmer
Impairments in emotion regulation are thought to have a key role in the pathogenesis of anxiety disorders, but the neurobiological underpinnings contributing to vulnerability remain poorly understood. It has been a long-held view that exaggerated fear is linked to hyperresponsivity of limbic brain areas and impaired recruitment of prefrontal control. However, increasing evidence suggests that prefrontal-cortical networks are hyperactive during threat processing in anxiety disorders. This study directly explored limbic-prefrontal neural response, connectivity and heart-rate variability (HRV) in patients with a severe anxiety disorder during incidental versus intentional emotion regulation...
2015: Translational Psychiatry
https://www.readbyqxmd.com/read/26441953/epicatechin-gallate-a-naturally-occurring-polyphenol-alters-the-course-of-infection-with-%C3%AE-lactam-resistant-staphylococcus-aureus-in-the-zebrafish-embryo
#17
Christina S Stevens, Helena Rosado, Robert J Harvey, Peter W Taylor
(-)-epicatechin gallate (ECg) substantially modifies the properties of Staphylococcus aureus and reversibly abrogates β-lactam resistance in methicillin/oxacillin resistant (MRSA) isolates. We have determined the capacity of ECg to alter the course of infection in zebrafish embryos challenged with epidemic clinical isolate EMRSA-16. At 30 h post fertilization (hpf), embryos were infected by injection of 1-5 × 10(3) colony forming units (CFU) of EMRSA-16 into the circulation valley or yolk sac. Infection by yolk sac injection was lethal with a challenge dose above 3 × 10(3) CFU, with no survivors at 70 hpf...
2015: Frontiers in Microbiology
https://www.readbyqxmd.com/read/26311238/selective-connexin43-inhibition-prevents-isoproterenol-induced-arrhythmias-and-lethality-in-muscular-dystrophy-mice
#18
J Patrick Gonzalez, Jayalakshmi Ramachandran, Lai-Hua Xie, Jorge E Contreras, Diego Fraidenraich
Duchenne muscular dystrophy (DMD) is caused by an X-linked mutation that leads to the absence of dystrophin, resulting in life-threatening arrhythmogenesis and associated heart failure. We targeted the gap junction protein connexin43 (Cx43) responsible for maintaining cardiac conduction. In mild mdx and severe mdx:utr mouse models of DMD, and human DMD tissues, Cx43 was found to be pathologically mislocalized to lateral sides of cardiomyocytes. In addition, overall Cx43 protein levels were markedly increased in mouse and human DMD heart tissues examined...
2015: Scientific Reports
https://www.readbyqxmd.com/read/26136298/p-wave-detection-and-delineation-in-the-ecg-based-on-the-phase-free-stationary-wavelet-transform-and-using-intracardiac-atrial-electrograms-as-reference
#19
Gustavo Lenis, Nicolas Pilia, Tobias Oesterlein, Armin Luik, Claus Schmitt, Olaf Dössel
Robust and exact automatic P wave detection and delineation in the electrocardiogram (ECG) is still an interesting but challenging research topic. The early prognosis of cardiac afflictions such as atrial fibrillation and the response of a patient to a given treatment is believed to improve if the P wave is carefully analyzed during sinus rhythm. Manual annotation of the signals is a tedious and subjective task. Its correctness depends on the experience of the annotator, quality of the signal, and ECG lead...
February 2016: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/26131782/is-heart-rate-complexity-a-surrogate-measure-of-cardiac-output-before-during-and-after-hemorrhage-in-a-conscious-sheep-model-of-multiple-hemorrhages-and-resuscitation
#20
Nehemiah T Liu, George C Kramer, Muzna N Khan, Michael P Kinsky, José Salinas
BACKGROUND: Despite its medical utility, continuous cardiac output (CO) monitoring remains a practical challenge on the battlefield and in the prehospital environment. Measuring a CO surrogate, perhaps heart-rate complexity (HRC), might be a viable solution when no direct monitoring of CO is available. Changes in HRC observed before and during hemorrhagic shock may be able to track the simultaneous changes in CO. The goal of this study was to test whether HRC is a surrogate measure of CO before, during, and after hemorrhage in a conscious sheep model of multiple hemorrhages and resuscitation...
October 2015: Journal of Trauma and Acute Care Surgery
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