ECG Findings (ecg + finding)

Distribution by Scientific Domains


Selected Abstracts


Molecular Genetic Analysis of PRKAG2 in Sporadic Wolff-Parkinson-White Syndrome

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2003
CARL J. VAUGHAN
Introduction: Mutations in the PRKAG2 gene that encodes the gamma2 regulatory subunit of AMP-activated protein kinase have been shown to cause autosomal dominant Wolff-Parkinson-White (WPW) syndrome associated with hypertrophic cardiomyopathy. Prior studies focused on familial WPW syndrome associated with other heart disease such as hypertrophic cardiomyopathy. However, such disease accounts for only a small fraction of WPW cases, and the contribution of PRKAG2 mutations to sporadic isolated WPW syndrome is unknown. Methods and Results: Subjects presented for clinical electrophysiologic evaluation of suspected WPW syndrome. WPW syndrome was diagnosed by ECG findings and/or by clinically indicated electrophysiologic study prior to enrollment. Echocardiography excluded hypertrophic cardiomyopathy. Denaturing high-performance liquid chromatography and automated sequencing were used to search for PRKAG2 mutations. Twenty-six patients without a family history of WPW syndrome were studied. No subject had cardiac hypertrophy, and only one patient had associated congenital heart disease. Accessory pathways were detected at diverse locations within the heart. Two polymorphisms in PRKAG2 were detected. [inv6+36insA] occurred in intron 6 in 4 WPW patients and [inv10+10delT] in intron 10 in 1 WPW patient. Both occurred in normal unrelated chromosomes. No PRKAG2 mutations were detected. Conclusion: This study shows that, unlike familial WPW syndrome, constitutional mutation of PRKAG2 is not commonly associated with sporadic WPW syndrome. Although polymorphisms within the PRKAG2 introns were identified, there is no evidence that these polymorphisms predispose to accessory pathway formation because their frequency is similarly high in both WPW patients and normal individuals. Further studies are warranted to identify the molecular basis of common sporadic WPW syndrome.(J Cardiovasc Electrophysiol, Vol. 14, pp. 263-268, March 2003) [source]


Rest Premature Ventricular Contractions on Routine ECG and Prognosis in Heart Failure Patients

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010
Vy-Van Le M.D.
Background: Premature ventricular contractions (PVC) at rest are frequently seen in heart failure (HF) patients but conflicting data exist regarding their importance for cardiovascular (CV) mortality. This study aims to evaluate the prognostic value of rest PVCs on an electrocardiogram (ECG) in patients with a history of clinical HF. Methods and Results: We considered 352 patients (64 ± 11 years; 7 females) with a history of clinical HF undergoing treadmill testing for clinical reasons at the Veterans Affairs Palo Alto Health Care System (VAPAHCS) (1987,2007). Patients with rest PVCs were defined as having ,1 PVC on the ECG prior to testing (n = 29; 8%). During a median follow-up period of 6.2 years, there were 178 deaths of which 76 (42.6%) were due to CV causes. At baseline, compared to patients without rest PVCs, those with rest PVCs had a lower ejection fraction (EF) (30% vs 45%) and the prevalence of EF , 35% was higher (75% vs 41%). They were more likely to have smoked (76% vs 55%). The all-cause and CV mortality rates were significantly higher in the rest PVCs group (72% vs 49%, P = 0.01 and 45% vs 20%, P = 0.002; respectively). After adjusting for age, beta-blocker use, rest ECG findings, resting heart rate (HR), EF, maximal systolic blood pressure, peak HR, and exercise capacity, rest PVC was associated with a 5.5-fold increased risk of CV mortality (P = 0.004). Considering the presence of PVCs during exercise and/or recovery did not affect our results. Conclusion: The presence of PVC on an ECG is a powerful predictor of CV mortality even after adjusting for confounding factors. Ann Noninvasive Electrocardiol 2010;15(1):56,62 [source]


Correlation of Noninvasive Electrocardiography with Invasive Electrophysiology in Syncope of Unknown Origin: Implications from a Large Syncope Database

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009
Konstantinos A. Gatzoulis
Background: The evaluation of syncope can be expensive, unfocussed, and unrevealing yet, failure to diagnose an arrhythmic cause of syncope is a major problem. We investigate the utility of noninvasive electrocardiographic evaluation (12-lead ECG and 24-hour ambulatory electrocardiographic recordings) to predict electrophysiology study results in patients with undiagnosed syncope. Methods: We evaluated 421 patients with undiagnosed syncope who had an electrocardiogram (ECG), an electrophysiology study, and 24-hour ambulatory monitoring. Noninvasive testing was used to predict electrophysiology testing outcomes. Multivariable logistic regression analysis adjusting for age, sex, presence of heart disease, and left ventricular ejection fraction (LVEF) was used to assess independent predictors for sinus node disease, atrioventricular node disease, and induction of ventricular tachyarrhythmias. Results: Patients were divided into four groups: group 1, abnormal ECG and ambulatory monitor; group 2, abnormal ECG only; group 3, abnormal ambulatory monitor; and group 4, normal ECG and ambulatory monitor. The likelihood of finding at least one abnormality during electrophysiologic testing among the four groups was highest in group 1 (82.2%) and lower in groups 2 and 3 (68.1% and 33.7%, respectively). In group 4, any electrophysiology study abnormality was low (9.1%). Odds ratios (OR) were 35.9 (P < 0.001), 17.8 (P < 0.001), and 3.5 (P = 0.064) for abnormal findings on electrophysiology study, respectively (first three groups vs the fourth one). ECG and ambulatory monitor results predicted results of electrophysiology testing. Conclusion: Abnormal ECG findings on noninvasive testing are well correlated with potential brady- or/and tachyarrhythmic causes of syncope, in electrophysiology study of patients with undiagnosed syncope. [source]


Electrical and Structural Remodeling in Left Ventricular Hypertrophy,A Substrate for a Decrease in QRS Voltage?

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2007
Ljuba Bacharova M.D., M.B.A., Ph.D.
Electrical remodeling in advanced stages of cardiovascular diseases creates a substrate for triggering and maintenance of arrhythmias. The electrical remodeling is a continuous process initiated already in the early stages of cardiological pathology. The aim of this opinion article was to discuss the changes in electrical properties of myocardium in left ventricular hypertrophy (LVH), with special focus on its early stage, as well as their possible reflection in the QRS amplitude of the electrocardiogram. It critically appraises the classical hypothesis related to the QRS voltage changes in LVH. The hypothesis of the relative voltage deficit is discussed in the context of supporting evidence from clinical studies, animal experiments, and simulation studies. The underlying determinants of electrical impulse propagation which may explain discrepancies between "normal" ECG findings and increased left ventricular size/mass in LVH are reviewed. [source]


Predictive Value of T-wave Abnormalities at the Time of Emergency Department Presentation in Patients with Potential Acute Coronary Syndromes

ACADEMIC EMERGENCY MEDICINE, Issue 6 2008
Kathy B. Lin BA
Abstract Objectives:, T-wave abnormalities on electrocardiograms (ECGs) are common, but their ability to predict 30-day cardiovascular outcomes at the time of emergency department (ED) presentation is unknown. The authors determined the association between T-wave abnormalities on the presenting ECG and cardiovascular outcomes within 30 days of presentation in patients with potential acute coronary syndromes (ACSs). Methods:, This was a secondary analysis of a prospective cohort study of ED patients that presented with a potential ACS. Patients were excluded if they had a prior myocardial infarction, ST-segment elevation or depressions, right or left bundle branch block, or Q-waves on the initial ECG. Data included demographics, medical and cardiac history, and ECG findings including the presence or absence of T-wave flattening, inversions of 1,5 mm, and inversions >5 mm. Investigators followed the hospital course for admitted patients, and 30-day follow-up was performed on all patients. The main outcome was a composite of death, acute myocardial infarction, revascularization, coronary stenosis greater than 50%, or a stress test with reversible ischemia. Results:, Of 8,298 patient visits, 5,582 met criteria for inclusion: 4,166 (74.6%) had no T-wave abnormalities, 721 (12.9%) had T-wave flattening in two or more leads, 659 (11.8%) had T-wave inversions of 1,5 mm, and 36 (0.64%) had T-wave inversions >5 mm. The composite endpoint was more common in patients with T-wave flattening (8.2% vs. 5.7%; p = 0.0001; relative risk [RR] = 1.4; 95% confidence interval [CI] = 1.1 to 1.9), T-wave inversions 1,5 mm (13.2% vs. 5.7%; p = 0.0001; RR = 2.4; 95% CI = 1.8 to 3.1), and T-wave inversions >5 mm (19.4% vs. 5.7%; p = 0.0001; RR = 3.4; 95% CI = 1.7 to 6.1), or any T-wave abnormality (10.8% vs. 5.7%; p = 0.0001; RR = 1.9; 95% CI = 1.6 to 2.3), even after adjustment for initial troponin. This association also existed in the subset of patients without known coronary artery disease. Conclusions:, In patients with potential ACS presenting to the ED, T-wave abnormalities are associated with higher rates of 30-day cardiovascular events. [source]