To test the feasibility of a small and simple system for telephonic transmission of 12-lead electrocardiograms (ECGs), 70 patients with acute coronary syndrome admitted to the cardiac care unit (CCU) were included in a feasibility study. The transmission system consisted of a belt with multiple electrodes, which was positioned around ...

OBJECTIVES: The purpose of this study was to describe the ECG profile of a cohort of patients with fasciculoventricular pathways and compare the profile with the ECG of patients with anteroseptal and midseptal accessory pathways. BACKGROUND: Electrophysiologic findings suggest fasciculoventricular pathways insert into the septal region. Findings also suggest the ...

OBJECTIVES: To determine the significance of sex in one-year prognosis of death from ischemic heart disease after a first-ever myocardial infarction. MATERIAL AND METHODS: Kaunas men and women aged 25-64 years and admitted to the hospitals of Kaunas due to a first-ever myocardial infarction during 1983-1992, and with a first ...

Bifocal RIGHT ventricular stimulation (BRIGHT) is an ongoing, randomized, single-blind, crossover study of atrial synchronized bi-right ventricular (RV) pacing in patients in New York Heart Association heart failure functional class III, a left ventricular ejection fraction <35%, left bundle branch block and QRS complexes >/=120 ms. This analysis compared the ...

Poor R-wave progression is a common ECG pattern, which is often inconclusively interpreted by medical directors. Although this ECG pattern is commonly attributed to anterior myocardial infarction, it may also be caused by left bundle branch block, Wolff-Parkinson-White syndrome, right and left ventricular hypertrophy as well as by faulty ECG ...

The T-wave of the electrocardiogram (ECG) is generated both from the left and the right ventricles of the heart. Each ventricle may produce a normal, an "ischemic", or a "secondary" T-wave, depending on segmental perfusion, intraventricular pressure, or QRS complex duration. The direction of the T-wave is determined by the ...

BACKGROUND: The extent of Q wave 'burden' on electrocardiograms (ECGs) has not been correlated with the extent of scarring and hibernation as determined quantitatively by positron emission tomography (PET). OBJECTIVE: A retrospective study was performed to identify if ECG Q wave burden predicts the extent of scarring or mismatch (hibernating ...

Hypothermia can result from exposure to a cold environment (e.g., accidental drowning) or it can be induced and used as a brain protection strategy (e.g., therapeutic hypothermia). One common ECG presentation with hypothermia is the J wave, which is related to the altered cellular activities during hypothermia. A case study ...

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia occurring in about 10-20% of patients with acute myocardial infarction (AMI). P-wave dispersion (PWd) and P-wave duration (PWD) have been used to evaluate the discontinuous propagation of sinus impulse and the prolongation of atrial conduction time, respectively. This study was conducted to ...

The purpose of this study was to validate the prognostic value of computer-derived measurements of the spatial alignment of ventricular depolarization and repolarization from the standard 12-lead ECG in a general medical population. Analyses were performed on the first ECG digitally recorded from 46,573 consecutive patients since 1987. QRS and ...

BACKGROUND: Onset of atrial fibrillation in hypertensive patients is usually associated with a high occurrence of cardiovascular complications. Therefore, it is important to assess non-invasively the risk of developing paroxysmal atrial fibrillation (PAF) in hypertensive patients during sinus rhythm. This study was undertaken to determine if hypertensive patients with history ...

INTRODUCTION: To clarify the mechanisms of abnormal Q waves in hypertrophic cardiomyopathy (HCM), local epicardial electrical activities were assessed by intracoronary electrocardiography (ECG). METHODS AND RESULTS: Unipolar intracoronary ECG was recorded by introducing a guide wire for angioplasty into the left anterior descending artery (LAD) in 20 patients with HCM ...

The pathogenesis of U-wave inversion and its clinical value are still not clear, although the U wave was described by Einthoven together with the other electrocardiographic (ECG) waves. Not considered a useful diagnostic clue, it is not usually mentioned in ECG reports. In recent years, stimulated by the long QT ...

AIMS: To investigate the prognostic value of T-wave abnormalities in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS), and whether such ECG changes may predict benefit from an early coronary angiography. Although ST-segment changes are considered the most important ECG feature in NSTE-ACS, T-wave abnormalities are the most common ECG ...

Cardiac involvement (CI) in form of myocardial thickening in a patient with genetically confirmed facioscapulohumeral muscular dystrophy (FSHMD) has not been reported. The patient is a 50-year-old male with a tandem repeat size of 17 and 14 kb in the D4Z4 locus on chromosome 4q35. The clinical cardiologic investigation was ...

We investigated whether spontaneous normalization of negative T waves (TWN) on infarct-related ECG leads (IRLs) in the chronic phase of Q wave anterior myocardial infarction (MI) could be a predictor of residual viability in infarct areas. We prospectively studied 35 patients (age 60 +/- 8.6 years) in the chronic phase ...

ST-segment elevations in the right ventricular lead and those greater in lead III than in lead II strongly suggest that right, rather than left circumflex, coronary arterial occlusion occurs in acute myocardial infarction in the inferior wall. Our study demonstrated that, in the very early stages of infarction, a T-wave ...

The type of acute coronary syndrome may account for different prognoses between men and women after myocardial infarction. This study assessed gender differences in 28-day mortality rates for first or recurrent Q-wave and non-Q-wave myocardial infarctions and unstable angina by using data from 5 registries that included 20,836 patients (24.8% ...

BACKGROUND: The significance of higher intercostal space electrocardiography (HICS ECG) for the detection of the Brugada sign was investigated. METHODS AND RESULTS: The subjects consisted of 113 cases (108 males, 5 females; mean age, 57+/-17 years) with incomplete right bundle branch block type QRS morphology and ST-segment elevation (>0.10 mV) ...

A variety of chemical and biological nonlinear excitable media, including heart tissue, can support stable, self-organized waves of activity in a form of rotating single-arm spirals. In particular, heart tissue can support stationary and meandering spirals of electrical excitation, which have been shown to underlie different forms of cardiac arrhythmias. ...

We use artificial neural networks (ANNs) to detect signs of acute myocardial infarction (AMI) in ECGs. The 12-lead ECG is decomposed into Hermite basis functions, and the resulting coefficients are used as inputs to the ANNs. Furthermore, we present a case-based method that qualitatively explains the operation of the ANNs, ...

BACKGROUND: Body surface potential mapping has been shown to be a useful tool in the diagnosis and localization of remote non-Q wave and Q wave myocardial infarction, but human expertise is required to interpret the maps. OBJECTIVE: To identify quantitative body surface potential mapping parameters that could enable a computer-based ...

The J wave is a deflection that appears on the surface ECG as a late delta wave following the QRS complex. Also known as an Osborn wave, the J wave has been observed in various conditions and diseases. Our case highlights the typical electrocardiographic manifestations of hypothermia including the J ...

Arrhythmogenic right ventricular dysplasia is an inherited disease causing fatty replacement of heart tissue. This disease often presents as T-wave inversion in the anterior leads of the electrocardiogram (ECG) with life-threatening ventricular arrhythmias. In older patients, progressive right and left ventricular failure can develop. This is a case report of ...

The implantable cardioverter defibrillator is the treatment of choice for patients with ventricular tachycardia, especially in the setting of structural heart disease, but inappropriate therapy continues to be a problem. In this report we describe a short case series of patients who presented with T wave oversensing. We propose a ...

BACKGROUND: Unrecognized myocardial infarctions (UMI) are detected by surveillance electrocardiograms (ECGs). In epidemiologic studies, different sets of ECG criteria have been used to define myocardial infarction, possibly contributing to significant differences in prevalence estimates and risk factor associations. We sought to summarize the rationale behind the various UMI-ECG definitions and ...

Electroconvulsive therapy (ECT) can lead to ST depression and arrhythmias in patients with coronary artery disease, most likely secondary to increased myocardial oxygen demand. This report describes a case of ECT-associated, global T-wave inversions in a patient with chronic atrial fibrillation treated with digoxin. Laboratory evaluation and echocardiography were normal. ...

OBJECTIVE: The appearance of new Q waves on the electrocardiogram (ECG) after cardiac surgery has been traditionally considered a sign of major myocardial tissue damage. The aim of this study was to investigate the clinical significance of new Q waves appearing following cardiac surgery and to correlate them with the ...

We present the evolutionary changes of isolated right ventricular infarction (RVI) in a patient undergoing right coronary artery stenting using a novel imaging system. Twelve ECG and body surface maps were recorded at 30-s intervals during right coronary angioplasty, during which a right ventricular branch of the right coronary artery ...

We describe a case of potentially fatal undersensing of VF by a third generation ICD with predetermined automatic gain control. In this patient, ventricular sensing was optimal, as R wave amplitudes during sinus rhythm were at least 16 mV. Cyclical, high amplitude signals during VF elevated the sensing floor to ...

The T-wave axis shift has been reported to represent a general marker of ventricular repolarization abnormalities and a potential indicator of increased risk for cardiovascular mortality. We assessed the prognostic importance of the T-wave axis deviation for mortality rate in patients with chronic Chagas' disease. In a long-term follow-up prospective ...

Although the damage in myocardial infarction has been demonstrated to be related with the magnitude and number of ST elevation, its relation with terminal distortion of QRS is unclear. The relationship between terminal QRS distortion in ECGs on admission and the results of early low dose dobutamine stress echocardiography (LDSE) ...

The goal of this study was to evaluate the role of a computerised, non-invasive ECG method for detecting acute coronary occlusion (ACO). Ninety-five standard ECG leads were recorded, before and during ACO, from 18 patients undergoing balloon angioplasty. ECG amplitude and derivative parameters were calculated for the ORS, ST and ...

The main purpose of this study was to describe electrocardiographic (ECG) changes in canine babesiosis, and to relate these to clinical severity, outcome and cardiac pathology. Four groups of dogs with babesiosis were studied: mild to moderate anemia, severe anemia, concurrent autoagglutination and concurrent complications. Lead II ECG was recorded ...

Micromachined probes, with iridium (Ir) microelectrodes on silicon shanks, were evaluated to assess their suitability for cardiac electrogram recording. The electrochemical activation (anodic oxidation) procedure for the circular Ir microelectrode was investigated using the square wave potential according to the electrode size, number of cycles, and cathodic-anodic potential level of ...

BACKGROUND: The common electrocardiographic subclassification of anterior acute myocardial infarction (AMI) is not reliable in presenting the exact location of the infarct. We investigated the relationship between predischarge electrocardiographic patterns and the extent and location of perfusion defects in 55 patients with first anterior AMI. METHODS: Predischarge electrocardiogram was examined ...

There is recent evidence that anasarca peripheral edema, irrespective of its etiology, attenuates ECG QRS potentials. Pulmonary edema (PE) also is thought to cause reduction in the amplitude of QRS complexes. The case reported herein is of a patient with severe PE, hypertension, left ventricular diastolic dysfunction, and no peripheral ...

OBJECTIVE: It is known that exercise-induced ischemia in patients with coronary artery disease (CAD) may produce QRS prolongation in the surface electrocardiogram (ECG). To investigate the presence of exercise-induced Q-wave prolongation in patients with single-vessel CAD and Q-wave myocardial infarction (MI), in association with the presence of reversible perfusion defects ...

BACKGROUND: Wilson's disease is known for its protean manifestations; however electrocardiographic abnormalities have not received much attention. AIM: To evaluate the various electrocardiographic (ECG) changes in patients with Wilson's disease. METHOD: The resting ECGs of 50 patients with Wilson's disease were systematically analyzed independently by three observers after excluding other ...

Surgically induced abnormalities in atrial conduction could result in unusual P wave changes. A 31-year-old woman underwent concomitant mitral valve surgery and atrial compartment operation for mitral stenosis and atrial fibrillation (AF). After operation, the AF was successfully converted to sinus rhythm, whereas an unusual electrocardiogram (ECG) with a discrete ...

We describe a patient with coronary artery disease who showed transiently augmented R-waves in his electrocardiogram (ECG) during the course of an exercise treadmill test (ETT), an ECG pattern occasionally associated with the hyperacute phase of myocardial infarction and variant angina. This change in the R-waves was noted in II, ...

We studied prospectively 35 elder women aged 65-82 years, with isolated severe symptomatic aortic stenosis, referred for aortic valve surgery. We assessed diastolic function by TEE before and after cardiac surgery, although follow-up data were collected in 26 patients. The examination was performed prior to surgery and 6 months after. ...

BACKGROUND: Left ventricular function is the most important determinant of prognosis following myocardial infarction. METHODS: A prospective analytical cohort study of 33 cardiac care unit survivors of acute myocardial infarction was performed to assess the accuracy, reproducibility and observer variation of the bedside Valsalva response in predicting an ejection fraction ...

Several studies have shown that diminution of the high-frequency (HF; 150-250 Hz) components present within the central portion of the QRS complex of an electrocardiogram (ECG) is a more sensitive indicator for the presence of myocardial ischemia than are changes in the ST segments of the conventional low-frequency ECG. However, ...

Progressive heart failure and ventricular fibrillation are major causes of death in patients with chronic heart failure. Mechanical alternans (pulsus alternans) has been observed in patients with severe congestive heart failure. Visible T wave alternans occasionally is a precursor of ventricular fibrillation. We investigated the occurrence of both cardiac alternans ...

BACKGROUND: Pulmonary embolism (PE) afflicts millions of individuals worldwide. Electrocardiography along with chest X-ray and arterial blood gas analysis represent the basic examinations to reinforce the clinical suspicion of PE. We describe the electrocardiographic (ECG) features in a series of patients with PE and a critical clinical presentation. METHODS: We ...

BACKGROUND: The actual relationship between the interval change of myocardial thallium 201 (Tl-201) radioactivity in the infarct area and the pattern of Q-wave regression is still unknown. This study was conducted to evaluate their relationship after acute myocardial infarction (AMI). METHODS AND RESULTS: A total of 30 patients who had ...

OBJECTIVES: We investigated whether patients with non-Q-wave myocardial infarction (NQMI) have more ischemic viable myocardium (IVM) than patients with Q-wave myocardial infarction (QMI). BACKGROUND: Non-Q-wave myocardial infarction is associated with higher incidences of cardiac events than QMI, suggesting more myocardium at risk in NQMI. METHODS: To identify myocardial ischemia, hibernation, ...

AIMS/HYPOTHESIS: Our study investigated the prognosis of Type 2 diabetic patients with silent myocardial infarction in a community-based cohort. METHODS: We analysed data from 1269 patients with Type 2 diabetes mellitus from a community-based observational study of diabetes care, control and complications. Silent myocardial infarction was defined as Q waves ...

BACKGROUND: It has been reported that recording electrocardiograms (ECGs) in the 3rd intercostal space (ICS) is one method that can be used for detecting Brugada syndrome; however, the prevalence of Brugada-type ECGs recorded in the 3rd ICS and the usefulness of recording the ECG in the 3rd ICS in accordance ...