Repolarization abnormalities

1986 ◽  
pp. 41-45
Author(s):  
P. Zeppilli ◽  
N. Aspromonte
Keyword(s):  
Repolarization Abnormalities

Dynamics of the QT intervals encompassing secondary repolarization abnormalities during sudden but transient lengthening of the RR intervals

2003 ◽  
Vol 91 (7) ◽  
pp. 883-885 ◽  
Author(s):  
Federico Moleiro ◽  
Agustin Castellanos ◽  
Jorge O. Diaz ◽  
Robert J. Myerburg
Keyword(s):  
Rr Intervals ◽  
Qt Intervals ◽  
Repolarization Abnormalities

Abstract 15002: Towards Unmasking Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy in the Early Concealed Stage

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Thomas P Mast ◽  
Arco J Teske ◽  
Jeroen F vd Heijden ◽  
Judith A Groeneweg ◽  
Pieter A Doevendans ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Arrhythmogenic Right Ventricular Dysplasia ◽  
Tissue Doppler ◽  
Doppler Imaging ◽  
Apical Region ◽  
Free Wall ◽  
Right Ventricular Dysplasia ◽  
Mutation Carriers ◽  
Increased Risk ◽  
Repolarization Abnormalities

Background: The concealed stage of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is associated with increased risk of sudden cardiac death. However, particular at this stage disease detection is hampered by absence of criteria. Activation delay (AD) is a hallmark of arrhythmogenesis in ARVD/C. Echocardiographic tissue Doppler imaging (TDI) may unmask AD in the absence of electrocardiographic (ECG) abnormalities. Methods: Three groups were compared 1) symptomatic definite ARVD/C patients with a mutation in the Plakophilin-2 ( PKP2) gene (n=37), 2) asymptomatic PKP2 mutation carriers (n=20) and 3) healthy controls (n=30). All groups underwent full echocardiographic examination with additional TDI of the right ventricular (RV) free wall and a routine 12-lead ECG recording. As surrogate for AD the electro-mechanical interval (EMI) was measured, defined as time between local first electrical deflection and local onset of mechanical shortening. EMI was measured in the subtricuspid, mid and apical region of the RV free wall. Detailed ECG analysis of depolarization (AD analysis) and repolarization abnormalities was performed in all subjects. Results: EMI was prolonged in all RV segments in ARVD/C patients compared to controls. Abnormal depolarization and repolarization was recorded in respectively 23 and 27 ARVD/C patients. In asymptomatic mutation carriers EMI was significantly prolonged in the subtricuspid area (Table 1). However, the ECG showed in 5/20 subjects only prolonged terminal activation duration and no repolarization abnormalities. Conclusion: TDI unmasks AD in both ARVD/C patients and asymptomatic mutation carriers. In asymptomatic mutation carriers EMI is prolonged in the subtricuspid area, whereas ECG appeared normal in the large majority. AD in the subtricuspid area is an early sign of disease in the concealed ARVD/C stage and may contribute to advanced risk stratification. Table 1: Results

Ionic mechanisms of electrophysiological properties and repolarization abnormalities in rabbit Purkinje fibers

2011 ◽  
Vol 300 (5) ◽  
pp. H1806-H1813 ◽  
Author(s):  
Alberto Corrias ◽  
Wayne Giles ◽  
Blanca Rodriguez
Keyword(s):  
Purkinje Cells ◽  
Mechanisms Of Action ◽  
Delayed Rectifier ◽  
Pharmacological Interventions ◽  
Drug Induced ◽  
Current Increase ◽  
Detailed Model ◽  
Purkinje Fibers ◽  
Electrophysiological Properties ◽  
Repolarization Abnormalities

Purkinje cells play an important role in drug-induced arrhythmogenesis and are widely used in preclinical drug safety assessments. Repolarization abnormalities such as action potential (AP) prolongation and early afterdeploarizations (EAD) are often observed in vitro upon pharmacological interventions. However, because drugs do not act on only one defined target, it is often difficult to fully explain the mechanisms of action and their potential arrhythmogenicity. Computational models, when appropriately detailed and validated, can be used to gain mechanistic insights into the mechanisms of action of certain drugs. Nevertheless, no model of Purkinje electrophysiology that is able to reproduce characteristic Purkinje responses to drug-induced changes in ionic current conductances such as AP prolongation and EAD generation currently exists. In this study, a novel biophysically detailed model of rabbit Purkinje electrophysiology was developed by integration of data from voltage-clamp and AP experimental recordings. Upon validation, we demonstrate that the model reproduces many key electrophysiological properties of rabbit Purkinje cells. These include: AP morphology and duration, both input resistance and rate dependence properties as well as response to hyperkalemia. Pharmacological interventions such as inward rectifier K+ current and rapid delayed rectifier K+ current block as well as late Na+ current increase result in significant AP changes. However, enhanced L-type Ca2+ current ( iCaL) dominates in EAD genesis in Purkinje fibers. In addition, iCaL inactivation dynamics and intercellular coupling in tissue strongly modulate EAD formation. We conclude that EAD generation in Purkinje cells is mediated by an increase in iCaL and modulated by its inactivation kinetics.

scholarly journals Assessment of repolarization abnormalities in baseline electrocardiograms of patients with myocarditis

2017 ◽  
Vol 47 ◽  
pp. 1333-1339 ◽  
Author(s):  
Hacı Murat GÜNEŞ ◽  
Gamze BABUR GÜLER ◽  
Ekrem GÜLER ◽  
Gültekin Günhan DEMİR ◽  
Mehmet Kamil TEBER ◽  
...  
Keyword(s):  
Repolarization Abnormalities

scholarly journals Electrocardiographic characteristics of patients with coronavirus disease 2019 (COVID-2019) related pneumonia at first presentation

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
U Nguyen ◽  
M Strik ◽  
S Abu-Arib ◽  
A Bruekers ◽  
T Nguyen ◽  
...  
Keyword(s):  
Clinical Presentation ◽  
Negative Group ◽  
Male Mortality ◽  
Funding Sources ◽  
Atrial Enlargement ◽  
Study Population ◽  
Polymerase Chain ◽  
Repolarization Abnormalities ◽  
Funding Acknowledgements

Abstract Funding Acknowledgements Type of funding sources: None. Purpose To evaluate electrocardiographic (ECG) characteristics at first presentation in patients with possible coronavirus disease (COVID-19) pneumonia. Methods and results 356 patients presenting at the emergency room with possible COVID-19 pneumonia based on clinical presentation and computed tomography findings were included and subdivided into a COVID-19 positive group ([COVID-19-positive], n = 231, 65%) and a COVID-19 negative group ([COVID-19-negative], n = 125, 35%) based on polymerase chain reaction tests. The study population was predominantly middle aged-elderly (67 ± 14 year; n = 235, 66% male). Mortality rate was 24% after 1-month follow-up. There were no significant (NS) differences in sex, age, and mortality between the COVID-19-positive and COVID-19-negative group.  Atrial fibrillation (AF) was common (9%), though its prevalence was NS (regression analyses adjusted for age and sex) different in the COVID-19-positive vs. the COVID-19-negative group. ECG characteristics reflecting atrial enlargement and repolarization abnormalities were frequently present (<38% and 14% respectively). No significant differences were found between the COVID-19-positive vs. the COVID-19-negative group for the majority of morphological ECG characteristics (Figure 1 for more detailed data).  Conclusion AF and ECG characteristics reflecting atrial enlargement and repolarization abnormalities are commonly present in COVID-19 patients. The prevalence of these ECG characteristics however do NS differ from their COVID-19-negative counterparts. Abstract Figure.

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