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Ghista Dhanjoo N - - 2010
The electrocardiogram (ECG) is a representative signal containing information about the condition of the heart. The shape and size of the P-QRS-T wave, the time intervals between its various peaks, may contain useful information about the nature of disease afflicting the heart. However, these subtle details cannot be directly monitored ...
Yu Jian - - 2009
1. The purpose of the present study was to explore the relationship between electrocardiogram (ECG) patterns of right ventricular outflow tract (RVOT) premature ventricular contractions and the three-dimensional distribution of the target sites. 2. Thirty-three consecutive patients were included in the study. The target sites were identified by non-contact mapping ...
LaBounty Troy - - 2009
BACKGROUND: Q-waves in ST-elevation acute coronary syndromes carry adverse implications. We sought to determine the frequency, predictors, and implications of Q-waves in the current era that includes primary percutaneous coronary interventions. METHODS: There were 14,916 patients evaluated in a multicenter observational study. They presented with ST-elevation acute coronary syndromes between ...
Patanè Salvatore - - 2010
The prevalence of the Brugada-type ECG and its natural history are still unclear. The Brugada syndrome is usually identified by a characteristic Brugada-type ECG that consists of ST elevation of a coved type in the precordial leads V1 to V3 and ventricular fibrillation that can lead to sudden cardiac death, ...
Lumlertgul Suthaporn - - 2009
BACKGROUND: Attenuation of electrocardiogram (ECG) QRS complexes is observed in patients with a variety of illnesses and peripheral edema (PERED), and augmentation with alleviation of PERED. Serial ECGs in stable individuals display variation in the amplitude of QRS complexes in leads V1-V6, stemming from careless placement of recording electrodes on ...
Dota Corina-Dana - - 2009
BACKGROUND: PC-based ECG measurements must cope with normal as well as pathological ECGs in a reliable manner. EClysis, a software for ECG measurements was tested against reference values from the Common Standards for Quantitative Electrocardiography (CSE) database. METHODS: Digital ECGs (12 leads, 500 Hz) were recorded by the CSE project. ...
Farha Khalid Abou - - 2009
Myocardial injury is one of the most notorious complications of a hypertensive crisis. Key electrocardiograph signs used to detect cardiac injury such as ST segment changes and cardiac arrhythmias usually indicate acute ongoing end-organ damage. Lack of early signs to predict end-organ damage might lead to a delay in the ...
Sedkowska Agnieszka - - 2009
Microvolt T-wave alternans (MTWA) is a promising non-invasive method of evaluating repolarization abnormalities. Its presence is strongly related to the occurrence of malignant ventricular tachyarrhythmias and is therefore regarded as a risk marker for sudden cardiac death. Most recent studies have described the usefulness of MTWA in selecting patients who ...
Karsikas Mari M Department Electrical and Information Engineering, Computer Engineering Laboratory PO BOX 4500, 90014 University of Oulu, Finland. - - 2009
Principal component analysis of vectorcardio-graphic T-wave loop has been shown to be a potential tool to describe the abnormality of the cardiac repolarization and to predict cardiac events in patients with cardiac disease. In this paper a new method for estimating the non-planarity of the T-wave loop is introduced and ...
Pislaru Cristina C Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55905, - - 2009
Diastolic properties of the myocardium are important for normal cardiac function and may contribute to the condition of heart failure. Measuring the viscoelastic properties of the left ventricular myocardium is difficult in vivo using noninvasive methods. In this study, we used a mechanical actuator to create harmonic, propagating mechanical waves ...
Nenadic Ivan I Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55905, USA. nenadic.ivan@ - - 2009
Stiffening of the left ventricle can compromise the ability of the heart to pump sufficient amounts of blood into the systemic circulation and could lead to heart failure. Quantifying mechanical properties of the left ventricular (LV) myocardium using a noninvasive technique would be of great benefit in clinical settings. We ...
Venkitachalam Lakshmi - - 2009
Percutaneous coronary intervention (PCI) has undergone rapid progress, both in technology and adjunct therapy. However, documentation of long-term temporal trends in relation to contemporary practice is lacking. We analyzed PCI use and outcomes in 8976 consecutive patients in the multicenter, National Heart, Lung, and Blood Institute-sponsored 1985-1986 percutaneous transluminal coronary ...
Minns Alicia B AB Department of Emergency Medicine, University of California, San Diego, San Diego, California 92103-8819, - - 2010
Marathon running has surged in popularity in the last quarter century. A small percentage of marathon runners develop increases of myocardial-specific markers with exercise, sometimes in the diagnostic range for acute myocardial infarction. A spectrum of abnormal electrocardiogram (ECG) patterns has also been described. ECG change specifically after marathon running ...
Calloe Kirstine K The Danish National Research Foundation Centre for Cardiac Arrhythmia, Department of Biomedical Sciences 12.5.10, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark. - - 2009
Transient outward potassium current (I(to)) is thought to be central to the pathogenesis of the Brugada syndrome (BrS). However, an I((to)) activator has not been available with which to validate this hypothesis. Here, we provide a direct test of the hypothesis using a novel I(to) activator, NS5806. Isolated canine ventricular ...
Strauss David G DG Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287, - - 2008
Myocardial scarring from infarction or nonischemic fibrosis forms an arrhythmogenic substrate. The Selvester QRS score has been extensively validated for estimating myocardial infarction scar size in the absence of ECG confounders, but has not been tested to quantify scar in patients with hypertrophy, bundle branch/fascicular blocks, or nonischemic cardiomyopathy. We ...
Puurtinen Merja - - 2009
New miniaturized portable electrocardiogram (ECG) measuring devices may require small interelectrode distance. However, finding a suitable location for a tiny measurement device may prove tedious, as reducing interelectrode distance reduces signal strength. The objective of the study was to define the optimal location for a very closely located (5 cm) ...
Goernig Matthias - - 2009
Electrocardiogram (ECG) particular from tiny, non Q-wave myocardial infarction may lack striking infarct pattern. Spatiotemporal correlation analysis (SCA) of multichannel magnetocardiogram (MCG) is a high-resolution "magnifying glass" to analyze homogeneity of repolarization. SCA involves full 4D spatiotemporal information to identify abnormalities as empirically done by eye in conventional ECG-but on ...
Madias John E - - 2008
A 63-year-old male patient with inferior infarction revealed transient attenuation of the Q-waves in II, III, and aVF, and R-waves in V1-V3 during an exercise stress test. Myocardial scintigraphy disclosed ischemia of the anterior wall and coronary arteriography, a 90% stenosis of the left main coronary artery (LMCA). The mechanism ...
Horácek B Milan - - 2008
Currently used electrocardiographic criteria for identifying patients with ST-elevation myocardial infarction (STEMI) perform with high specificity but low sensitivity. Our aim was to enhance ischemia-detection ability of conventional STEMI criteria based on 12-lead electrocardiogram (ECG) by adding new criteria using 3 vessel-specific leads (VSLs) derived from 12-lead ECG. Study data ...
Madias John E - - 2009
This viewpoint expresses reservations about using the inverse (or negative) aVR lead in the so-called Cabrera limb lead sequence and the implementation of inverse representations of any of the other 12 standard electrocardiographic leads. Instead, the author proposes that in patients with suspected acute coronary syndromes and a nondiagnostic electrocardiographic ...
Neurauter Andreas - - 2008
BACKGROUND: Countershock outcome prediction using ventricular fibrillation (VF) feature analysis needs undisturbed electrocardiogram (ECG) signals and therefore requires interruption of cardiopulmonary resuscitation (CPR). Features that originate from higher frequency bands of the VF power spectrum may be less affected by CPR artefacts and as such reduce cumulative hands-off intervals. MATERIALS ...
Batchvarov Velislav N - - 2008
We tested the hypothesis that ventricular repolarization of the first sinus beat following a ventricular premature beat (VPB) can be modulated in the absence of clearly discernible T-wave changes. We applied principal component analysis (PCA) to assess QRS and T-wave complexity of sinus beats preceding and following VPBs in multiple ...
Ariyarajah Vignendra - - 2008
Abnormal U waves (unduly larger or misshapen) are associated with several conditions such as hypokalemia, arrhythmias, cardiac ischemia, ventricular hypertrophy, and hypertension. Abnormal U waves have also been linked to certain cardiac medications, predominantly antiarrhythmics. However, mechanisms of U-wave-abnormality remains debated and perhaps elusive with the true U-wave relationship to ...
Nikas Dimitrios N DN Michaelideion Cardiac Centre, Ioannina Medical School, Ioannina, - - 2008
Several antioxidants have been found to have conflicting results in attenuating myocardial reperfusion injury. These studies were done primarily in experimental protocols that did not approximate clinical situations. The aim of this study was to test the efficacy of 3 different antioxidants (ascorbic acid [AA], desferrioxamine, and N-acetylcysteine [NAC]) administered ...
Drew Barbara J - - 2008
Mason-Likar or proprietary reduced lead (RL) configurations are used for continuous 12-lead electrocardiogram (ECG) monitoring. Because each RL set has a different electrode configuration and derivation, they are inherently different and should not be compared with each other or with the Mason-Likar or standard ECG to determine changes in an ...
Gregg Richard E - - 2008
A 12-lead electrocardiogram (ECG) reconstructed from a reduced subset of leads is desired in continued arrhythmia and ST monitoring for less tangled wires and increased patient comfort. However, the impact of reconstructed 12-lead lead ECG on clinical ECG diagnosis has not been studied thoroughly. This study compares the differences between ...
Vivo Rey P - - 2008
We describe a 65-year-old woman with a history of hypertension and smoking who presented with an acute episode of chest pain precipitated by severe emotional stress. Her initial electrocardiogram done in the emergency room showed non-specific T wave changes in the lateral leads and her cardiac troponin levels were mildly ...
de Luna Antoni Bayés - - 2008
AIMS: To study the different QRS patterns in leads V1 and V2 in first inferior, lateral, and combined inferolateral myocardial infarction (MI) to recognize which are the ECG criteria that best define the presence of lesions isolated to the anatomically lateral wall of the left ventricle. METHODS AND RESULTS: We ...
Kimura Shinpei - - 2010
We describe a 36-year-old woman with inverted Takotsubo cardiomyopathy caused by pheochromocytoma crisis. In the acute phase, her electrocardiogram showed ST segment depression in lead II, III, aVF and V2 through V5. On day 14, tall upright T-waves were observed in leads V2 through V5 despite heart failure and basal ...
Kjaergaard Marie - - 2009
BACKGROUND: The prevalence of coronary heart disease among Greenland Inuit today is similar to that of western populations. The cardiovascular risk profile among Inuit has changed over the past four decades with the introduction of a western life style. An unaltered prevalence of coronary heart disease has been proposed, but ...
Taylor Allen J - - 2008
Electrocardiographic findings indicating myocardial disease, such as left ventricular hypertrophy or ST-T wave abnormalities, or the presence of coronary artery calcium, indicating atherosclerotic coronary artery disease, are both biomarkers of future cardiovascular (CV) risk. Although the risk factors for myocardial and coronary artery disease are similar, their concomitant expression has ...
Jeon Hui-Kyung - - 2008
BACKGROUND: The present study evaluates the lack of Q waves on the electrocardiogram (ECG) in the prediction of myocardial viability compared with dobutamine stress echocardiography (DSE) and rest-redistribution thallium-201 (Tl-201) scintigraphy. HYPOTHESIS: The lack of pathologic Q waves (NoQ) may be a readily available and specific marker for the presence ...
Riera Andrés Ricardo Pérez - - 2008
Wellens syndrome is a clinical-electrocardiographic entity also referred to as left anterior descending (LAD) coronary T-wave syndrome or acute coronary T-wave syndrome. It is a complex of symptoms and signals indicating the existence of an undesirable condition secondary to critical high-grade proximal stenosis of the LAD coronary artery characterized by ...
Latha R - - 2008
High sensitive C-reactive protein (hs-CRP), a non-specific marker of inflammatory status has considerable interest focused due to its ability to predict myocardial infarction, stroke, peripheral arterial disease and sudden cardiac death. Alcoholics are known to be associated with inflammation of heart. This study was taken up to look for an ...
Viitasalo Matti - - 2008
BACKGROUND: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is characterized by risk of polymorphic ventricular tachycardia (pVT) and sudden death during stress. Experimental CPVT models show that delayed afterdepolarization (DAD)-induced triggered activity is the initiating mechanism of pVT, whereas an increase in transmural dispersion of repolarization (TDR) controls degeneration of pVT to ...
Ortega-Carnicer Julián - - 2008
A patient in whom moderate hypothermia developed after prolonged cardiopulmonary resuscitation is described. Hypothermia was manifested by transient electrocardiogram changes, including long QT, precordial J waves, and downsloping ST-segment elevation ending in a negative T wave in leads V(1) and V(2) resembling the Brugada syndrome. The physiopathologic mechanisms of these ...
Janata Andreas - - 2008
BACKGROUND: Long-term monitoring of patients at risk of arrhythmias would benefit from a miniaturized device. This study evaluated the quality of electrocardiogram (ECG) signals recorded by a miniaturized ECG recorder. METHODS: ECG data were concurrently recorded with an investigational device (Philips Medical Systems, Seattle, WA, USA) and a Holter recorder ...
De Roock Sophie - - 2008
BACKGROUND: Tako-tsubo syndrome (TTS) refers to the apical ballooning of the left ventricle observed when angiographic ventriculography is performed in patients presenting with electrocardiographic changes suggestive of acute coronary syndrome (new transient ST-segment deviation (>0.05 mV) or T-wave inversion (>0.2 mV)), mild elevation of cardiac markers, but normal coronary arteries ...
Pahlm Olle - - 2008
For a 12-lead resting electrocardiogram (ECG) to be considered "standard," limb electrodes should be placed distally on the limbs. When resting ECGs are taken in conjunction with an ECG-monitoring situation, so-called monitoring sites (as described by Mason and Likar and also others) on the torso are used. Numerous publication have ...
Man Sum-Che - - 2008
Electrocardiograms (ECGs) made with Mason-Likar electrode configuration (ML-ECGs) show well-known differences from standard 12-lead ECGs (Std-ECGs). We recorded, simultaneously, Std-ECGs and ML-ECGs in 180 subjects. Using these ECGs, 8 x 8 individual and general conversion matrices were created by linear regression, and standard ECGs were reconstructed from ML-ECGs using these ...
Lawless Christine E - - 2008
PURPOSE: Electrocardiography (ECG) has been proposed as a method to enhance the ability of the preparticipation examination (PPE) to detect underlying cardiac conditions that can lead to sudden cardiac death (SCD) in young athletes. METHODS AND RESULTS: We conducted a Medline review of the published medical literature, using the key ...
Kocoglu Hasan H Department of Anesthesiology, Faculty of Medicine, Abant Izzet Baysal University, Bolu, - - 2008
Preconditioning might protect the myocardium against ischemia/ reperfusion injury by reducing infarct size and preventing arrhythmias. Dexmedetomidine (DEX) is a highly selective α2-agonist used for sedoanalgesia in daily anesthetic practice. The cardioprotective effects of DEX on infarct size and on the incidence of arrhythmias observed after regional ischemia/reperfusion injury in ...
Azawi O I - - 2009
The aim of the present study was to test the hypothesis of wave pattern of follicular growth and to monitor the ovarian follicular dynamic in Iraqi buffalo cows. Reproductive tracts were collected at random intervals slaughtered at Mosul abattoir. According to morphological appearance of the corpus luteum, the estrous cycle ...
Hamlin Robert L - - 2008
This article explains the principles of electrocardiography, and explains how it is used by Safety Pharmacology, with a focus on the requirement for multiple leads in Safety Pharmacology assessment. Electrocardiography as used in different disciplines (e.g., medicine, anesthesiology, physiology, and pharmacology/toxicology/safety pharmacology) has different requirements for the number of electrodes ...
Nagase Satoshi - - 2008
OBJECTIVES: We examined the relationship between repolarization abnormality and coved-type ST-segment elevation with terminal inverted T-wave (type 1 electrocardiogram [ECG]) in patients with Brugada syndrome (BrS). BACKGROUND: Recent experimental studies have suggested that accentuation of the right ventricular action potential (AP) notch preferentially prolongs epicardial AP causing inversion of the ...
Sinno Mohamad C N - - 2008
BACKGROUND: Changes in the amplitude of the R wave (RWA) on the electrocardiogram (ECG) have been described during acute myocardial ischemia and infarction. However, this has not been well studied in a controlled setting. We hypothesized that significant increase in RWA occurs during early transmural myocardial ischemia. METHODS: We prospectively ...
Dagres Nikolaos - - 2009
Differentiation between left- and right-sided inferoseptal accessory pathways by existing ECG algorithms is unsatisfactory. We reviewed the 12-lead ECGs of 113 consecutive patients undergoing successful ablation of a single manifest inferoseptal pathway (40% at the mitral, 60% at the tricuspid annulus). For prediction of a right-sided location, the most useful ...
Ariyarajah Vignendra - - 2008
Left atrial enlargement is predictive of cardiovascular events. The predictive power, however, of the combination of electrocardiographic (LAE-ECG) and echocardiographic left atrial enlargement (LAE-Echo) has not been extensively evaluated. We prospectively identified patients admitted with non-ST-segment elevation myocardial infarction (NSTEMI) who developed new-onset heart failure during admission. Baseline electrocardiograms obtained ...
Toosi Mehrdad Seilanian - - 2008
Precise recording of the standard 12-lead electrocardiogram (ECG) is technically time consuming. Placing limb leads on the torso has the major advantages of ease of use, increased speed of application, and decreased artifact. This modified ECG frequently substitutes for the standard 12-lead ECG in intensive care units to detect ischemia, ...
Bour Jean - - 2008
Impedance cardiography (ICG) charts the rises and falls of thoracic impedance as the fluid content of the chest changes with each heartbeat. Breathing, arrhythmia, movements and posture interfere with the ICG. Modern pattern recognition software can now produce a composite signal-averaged ICG that considerably simplifies interpretation. The first derivative velocity ...
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