Search Results
Results 351 - 400 of 715
< 3 4 5 6 7 8 9 10 11 12 13 >
Perez Marco V - - 2009
BACKGROUND: The resting 12-lead electrocardiogram (ECG) remains the most commonly used test in evaluating patients with suspected cardiovascular disease. Prognostic values of individual findings on the ECG have been reported but may be of limited use. METHODS: The characteristics of 45,855 ECGs ordered by physician's discretion were first recorded and ...
Stengl Milan - - 2008
OBJECTIVE: Sepsis has been defined as the systemic host response to infection with an overwhelming systemic production of both proinflammatory and anti-inflammatory mediators. Continuous hemofiltration has been suggested as possible therapeutic option that may remove the inflammatory mediators. However, hemodialysis and hemofiltration were reported to influence cardiac electrophysiologic parameters and ...
Rimoldi Stefano F - - 2008
Left anterior hemiblock (LAHB) is the most frequent conduction abnormality, but its impact on the diagnostic accuracy of the exercise ECG has not been studied. The aim of our study was to determine the diagnostic accuracy of ST depression for predicting ischaemia in the presence of LAHB. Consecutive patients with ...
Myers Debbie A - - 2008
Electrocardiograms (ECGs) are a good baseline test for assessing cardiac rhythm. ECGs have not been reported in any zebra species and in very few Perissodactyla species. Standard limb, six-lead ECGs were recorded in 23 anesthetized Grevy's zebras (Equus grevyi). Heart rate, RR interval, P-wave duration, RR maximum/minimum, PR interval, QRS ...
Chiang Yi-Ju - - 2008
We demonstrate a two-handed metamaterial (THM), composed of highly symmetric three-layered structures operated at normal incidence. Not only does the THM exhibit two distinct allowed bands with right-handed and left-handed electromagnetic responses, but posses a further advantage of being independent to the polarizations of external excitations. In addition, the THM ...
Ramaswamy Prema - - 2009
OBJECTIVE: To determine the efficacy of electrocardiography (ECG) in detecting left ventricular hypertrophy (LVH) in pediatric hypertension (HT). STUDY DESIGN: Concomitant echocardiograms and electrocardiograms in 108 children with HT were reviewed. Left ventricular mass (LVM), assessed by echocardiography, was used as a basis for a diagnosis of LVH (echo LVH) ...
Koskela Jenni - - 2008
T-wave alternans (TWA) in electrocardiography (ECG) is a marker of cardiac repolarization, the molecular regulation of which is incompletely understood. High TWA and prolonged QT intervals are both associated with ventricular arrhythmias and sudden death. Therefore, we tested the hypothesis of whether the same mutations that influence the QT interval ...
Mirza Muzna - - 2008
BACKGROUND AND OBJECTIVE: Cardiopulmonary resuscitation (CPR) with adequate chest compression depth appears to improve first shock success in cardiac arrest. We evaluate the effect of simplification of chest compression instructions on compression depth in dispatcher-assisted CPR protocol. METHODS: Data from two randomized, double-blinded, controlled trials with identical methodology were combined ...
Ellestad Myrvin H - - 2008
Because of the failure to consider some of the unconventional electrocardiographic signs of ischemia during exercise testing, its sensitivity and specificity are lower than optimum. Two cases are presented to illustrate how precordial peaking of the T waves and lead-strength calculations in patients with low-voltage R waves can be used ...
Severens Els - - 2008
Event-related potentials were used to study whether factors known to influence subject-verb number agreement in production exert analogous effects on sentence comprehension. Participants read Dutch sentences containing subject-verb number agreement errors while their brainwaves were measured. The determiner of the singular head noun could be ambiguous or unambiguous in number ...
Fujiwara Shizuo - - 2008
A new apparatus has been built that annexes a normal electrocardiograph, ECG, with the aim to enhance its capacity. It adds the normal ECG power to superpose multiple records of ECG altogether and averages out them and, further, makes sophisticated analysis, such as normalizing the peak heights, evaluating the half-line ...
Srivathsan Komandoor - - 2008
A 27-year-old male with congenital long QT syndrome, SCN5A mutation experienced recurrent inappropriate exercise-related implantable cardioverter defibrillator (ICD) shocks. This device showed T-wave oversensing with double, which lead to these device discharges. Dynamic T-wave oversensing was reproducibly provoked at exercise treadmill testing and was confirmed as the mechanism leading to ...
Wallbom Agnes S - - 2008
OBJECTIVES: The purpose of the study is to investigate changes in F wave parameters after exercise in subjects with symptomatic lumbar spinal stenosis. DESIGN: A total of 19 older patients with lumbar spinal stenosis and neurogenic claudication participated in this cohort study. No one withdrew for adverse effects. All subjects ...
Haapalahti Petri - - 2008
OBJECTIVES: In LQT1 subtype of inherited long QT syndrome, repolarization abnormalities originating from defective I(Ks) render patients vulnerable to ventricular arrhythmia during sudden sympathetic activation. Experimental studies show lower I(Ks) density and longer action potential duration in left (LV) than in right (RV) ventricle. We studied interventricular dispersion of repolarization ...
Kounalakis Stylianos N SN Department of Sport Medicine and Biology of Exercise, Faculty of Physical Education and Sport Science, University of Athens , - - 2008
The purpose of this study was to examine the role of active muscle mass on cardiovascular drift (CVdrift) during prolonged exercise. Twelve subjects with peak oxygen uptake (VO2peak) of 3.52 ± 0.52 L·min(-1) (mean ± SD) cycled for 55 min with 80 revolutions per minute with either two legs (2-legged) ...
Sekhri Neha - - 2008
To determine whether resting and exercise electrocardiograms (ECGs) provide prognostic value that is incremental to that obtained from the clinical history in ambulatory patients with suspected angina attending chest pain clinics. Multicentre cohort study. Rapid access chest pain clinics of six hospitals in England. 8176 consecutive patients with suspected angina ...
Bitzen Alexander - - 2007
BACKGROUND: Patients with atrial fibrillation (AF) often exhibit abnormalities of P wave morphology during sinus rhythm. We examined a novel method for automatic P wave analysis in the 24-hour-Holter-ECG of 60 patients with paroxysmal or persistent AF and 12 healthy subjects. METHODS: Recorded ECG signals were transferred to the analysis ...
Laeseke Paul F PF Department of Biomedical Engineering, University of Wisconsin, 600 Highland Avenue, Madison, Wisconsin 53792, - - 2007
To compare multiple-electrode radiofrequency (RF) ablation versus RF ablation with a cluster electrode in an in vivo porcine kidney model. Thirteen female pigs (mean weight, 45 kg) were used for the study. In each animal, RF ablations were performed for 12 minutes with a conventional cluster electrode in one kidney ...
Smith Fiona E - - 2007
OBJECTIVE: Automated techniques were developed for the measurement of cardiac repolarisation using magnetocardiography. METHODS: This was achieved by collaboration with the Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany and the Grönemeyer Institute of Microtherapy, Bochum, Germany, to obtain recordings of magnetocardiograms (MCGs) in cardiac patients and healthy subjects. Manual and automated ventricular ...
Yoshida Soichiro - - 2007
The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones ...
Levine Saul D - - 2007
The Taser (TASER International, Scottsdale, AZ) is a high-voltage, low-amperage device used by many law enforcement agencies. Our objective in this study was to evaluate for rhythm changes utilizing cardiac monitoring during deployment of the Taser on volunteers. A prospective, observational study evaluated law enforcement personnel who had continuous electrocardiographic ...
Lampert Rachel - - 2007
INTRODUCTION: While implantable defibrillator shocks save lives, shock can lead to ventricular arrhythmias. However, the mechanism of shock-related proarrhythmia remains unclear. We evaluated the impact of ICD shock on repolarization instability, a factor associated with ventricular arrhythmogenesis. METHODS AND RESULTS: Sixty-five patients with ICDs underwent ambulatory ECG monitoring during defibrillation ...
Kligfield Paul - - 2007
BACKGROUND: The global QT interval, emerging as a standard measurement provided by digital electrocardiographs, is defined by the earliest QRS onset and latest T-wave offset that occur in any of the standard leads. Differences between global ECG measurements and those from individual ECG leads have implications for the redefinition of ...
Zhong Jing-quan - - 2007
The gap junction modifier Rotigaptide (ZP123), which promotes cellular coupling, was hypothesized to decrease defibrillation thresholds during prolonged ventricular fibrillation (VF). Thirty-two New Zealand white rabbits were randomized to receive saline (control, n = 16) or Rotigaptide (n = 16). Following 4 min of untreated VF, biphasic defibrillation shocks were ...
Argyriou A A - - 2007
OBJECTIVE: To prospectively detect significant transient F wave abnormalities obtained after exercise in patients with peripheral arterial disease (PAD) and to assess the potential diagnostic sensitivity of dynamic F wave study in such a context. PATIENTS AND METHODS: A series of 40 electrical stimuli were delivered to the peroneal and ...
Inglis J Greig - - 2007
The purpose of this research was to identify the number of sessions required for a new investigator to become proficient at evoking an H-reflex in the flexor carpi radialis (FCR), in comparison to an experienced investigator. 31 students from Brock University in the greater Niagara region (16 women M age ...
Cabasson A A Laboratory I3S-CNRS, University of Nice-Sophia Antipolis, 2000 Route des Lucioles, Sophia Antipolis cedex, France. - - 2007
The analysis of the heart period series is a difficult task especially under graded exercise conditions. Having a good tool to characterize the P-R and R-R intervals, i.e. a good method of time delay estimation, would carry out a better knowledge of the neural activity during exercise and recovery in ...
Bast Thomas - - 2006
Source localization using single current dipoles estimates equivalent centers of the spiking gray matter. The extent of the active cortex, however, is difficult to assess from scalp EEG because of the unknown individual volume conduction. The spatial scatter of dipole localizations of single spikes has been proposed as a measure ...
Lobodzinski Suave M - - 2006
We have developed a new biopotential fiber sensor (BFS) technology as an alternative to traditional wet-gel Ag/AgCl electrodes in long-term monitoring applications. Biopotential fiber sensor technology uses proprietary method of bonding copper sulfide to the surface of acrylic fibers, thus creating an electrically conductive medium (10(-1) ohms/cm). Surface modified bundles ...
Laeseke Paul F PF Department of Radiology, University of Wisconsin, Box 3252, Clinical Science Center-E3, 600 Highland Ave, Madison, WI 53792, USA. - - 2006
To prospectively evaluate, in vivo in pigs, an impedance-based multiple-electrode radiofrequency (RF) ablation system for creation of confluent areas of hepatic coagulation. The study was preapproved by the institutional research animal care and use committee. A prototype multiple-electrode RF system that enables switching between three electrically independent electrodes at impedance ...
Ariyarajah Vignendra - - 2006
Interatrial block (IAB), as denoted by P waves > or =110 ms in duration, is believed to be associated with underlying ischemia, particularly with that of its principal interatrial conduction pathway, the Bachmann bundle. In this study, the association between Duke prognostic treadmill (DPT) scores and change in P-wave duration ...
Nottin S - - 2006
Pulse wave velocity measurement is used as an index of arterial stiffness. The purpose was to evaluate the reproducibility of pulse wave velocity measurement at rest, during exercise and recovery from exercise, using an automated device. Twelve healthy young adults (mean age 22.0 +/- 3.1 yrs) underwent an upright submaximal ...
Vlachopoulos Charalambos - - 2006
OBJECTIVE: While most studies have shown an inverse relation between tea consumption and cardiovascular risk, other studies have shown opposite results. Aortic stiffness and wave reflections are markers of cardiovascular disease and prognosticators of cardiovascular risk. METHODS: The acute effect of black and green tea on aortic stiffness and wave ...
Aizawa Yoshiyasu - - 2006
Although catecholaminergic polymorphic ventricular tachycardia (CPVT) is associated with fatal ventricular arrhythmias and sudden death, the ECG findings are not fully understood. In this paper, we report on alterations in the U-wave. Seven patients from 6 families with CPVT in which bidirectional tachycardia and polymorphic VT were induced by exercise ...
Chattipakorn Nipon - - 2006
BACKGROUND: Ventricular fibrillation (VF) can be induced when a strong shock is delivered during the vulnerable period of a cardiac cycle. VF, however, cannot be induced if the shock strength is increased to the "upper limit of vulnerability" (ULV) level. Docosahexaenoic acid (DHA) has been shown to prevent the occurrence ...
Greene Barry R - - 2006
An investigation of changes in the neonatal electrocardiogram (ECG) and respiration signals from labelled seizure data for five neonatal patient records is reported. A decrease during seizure of 5.70% in the mean RR-interval was found. The mean respiration rate per epoch was found to decrease by a mean 18.44% during ...
McAllister Wallace R - - 2006
Subjects in six experimental groups (n = 16 each) received one-trial passive avoidance (PA) training in which shock was delivered upon movement from a white wooden floor compartment to a black grid compartment. Then fear was extinguished (30 min) in the black compartment. After either 24 or 168 h, all ...
Tran Quan T QT University of Queensland , Brisbane, Queensland, - - 2006
The purpose of this study was to investigate the effects of three different weight training protocols, that varied in the way training volume was measured, on acute muscular fatigue. Ten resistance-trained males performed all three protocols which involved dynamic constant resistance exercise of the elbow flexors. Protocol A provided a ...
Ghanem Raja N RN Cardiac Rhythm Disease Manage., Medtronic Inc., Minneapolis, MN 55432, USA. - - 2006
Body surface Laplacian mapping localizes cardiac activity and provides more detailed distributions compared to body surface potential mapping. Systematic comparison of the performance of bipolar and Laplacian ECGs during noise has not been performed. To determine whether Laplacian ECGs (2.5 cm diameter concentric rings) can reduce noise (myopotential and motion ...
Vehkaoja Antti T AT Inst. of Meas. & Inf. Technol., Tampere Univ. of - - 2006
A miniature wireless node for ECG measurements is presented. The ECG node is designed to be used in various applications including measurement of heart rate during physical exercise and continuous long term measurement of ECG for people assumed having, or being recovering from a cardiac disease. The ECG node is ...
Onuaguluchi Gilbert - - 2006
The electrocardiographic (ECG) profile of oral piperazine citrate was determined in healthy volunteers. Piperazine caused reduction in heart rate in all the subjects. The highest percentage of change was 15.7. The average pretreatment (73.6+/-6.59 beats/min) when compared with the heart rate 1 hour after piperazine was administered (64.6+/-5.21 beats/min) was ...
Tanskanen Jarno M A JM Ragnar Granit Institute, Tampere University of Technology, Tempere, Finland. - - 2006
Independent component analysis (ICA) of measured signals yields the independent sources, given certain fulfilled requirements. Properly parameterized signals provide a better view to the considered system aspects, while reducing the amount of data. It is little acknowledged that appropriately parameterized signals may be subjected to ICA, yielding independent components (ICs) ...
Josephsen Gary D - - 2005
This is a report of the adaptation of microwave processing in the preparation of liver biopsies for transmission electron microscopy (TEM) to examine ultrastructural damage of mitochondria in the setting of metabolic stress. Hemorrhagic shock was induced in pigs via 35% total blood volume bleed and a 90-min period of ...
Kay Bartholomew B Massey University , Institute of Food, Nutrition, and Human Health, Palmerston North, New - - 2005
This investigation assessed the effects of immediate or delayed re-hydration post-exercise, on mean arterial blood pressure (MAP) and on blood plasma volume (PV) expansion post-exercise. It was hypothesised that fluid ingestion would raise MAP and attenuate PV expansion. On two occasions separated by seven days, eight males (age 20.4 ± ...
Huang Damin - - 2005
Today, radio-frequency ablation has been shown to be a safe and effective method to treat paroxysmal tachycardia with Wolff-Parkinson-White syndrome. The many criteria reported for localizing the sites of accessory pathways from a 12-lead electrocardiogram have not proven adequate to differentiate the correct sites of accessory pathways for all situations. ...
Rahimi Rahman R Department of Physical Education and Sports Science, Razi University , Kermanshah, - - 2005
The purpose of this research was to compare effect 3 different rest intervals on the squat volume completed during a workout. Twenty college-aged men volunteered to participate in this study (age 20.73 ± 2.60 years; body mass 80.73 ± 10.80 kg). All subjects performed 3 testing sessions, during which 4 ...
Madias John E - - 2006
The aim of this study was to evaluate whether change in the patients' position during the electrocardiogram (ECG) recording alters the various components of the ECG curve. Concerns whether ECGs in medically compromised patients recorded in a sitting position should be considered "standard" tracings and whether ECGs recorded in the ...
Xia Yunlong - - 2005
The ECG interval from the peak to the end of the T wave (Tpeak-Tend) has been used as an index of transmural dispersion of ventricular repolarization (DVR). The correlation between the Tpeak-Tend interval and the global DVR, however, has not been well-evaluated. METHODS: Monophasic action potentials (MAPs) were recorded from ...
Winful Herbert G - - 2005
Recent papers suggest that tunneling wave packets traverse the region of allowed propagation between two potential barriers with superluminal group velocity and in a time independent of barrier separation. This phenomenon has been termed the "generalized Hartman effect" and extended to multiple barriers. Here we show that this delay time ...
Davids Jennifer S - - 2005
OBJECTIVES: To determine whether participation in an outpatient cardiac rehabilitation (OCR) program increases exercise levels and decreases shocks in patients with implantable cardioverter-defibrillators (ICDs). DESIGN: Retrospective comparative survey. SETTING: University tertiary-care ICD clinic. PARTICIPANTS: Patients with ICDs and coronary artery disease. INTERVENTION: Participation in OCR (nonrandomized). MAIN OUTCOME MEASURES: Exercise ...
< 3 4 5 6 7 8 9 10 11 12 13 >