Short and long QT syndromes: does QT length really matter?Jean Philippe Couderc
Center for Quantitative Electrocardiography and Cardiac Safety, Department of Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
J Electrocardiol 43:396-9. 2010
..In this review, we discuss these mechanisms and provocatively question the role of the QT interval duration as a surrogate marker of increased risk for arrhythmia in both the LQTS and the SQTS...
- T-wave morphology abnormalities in benign, potent, and arrhythmogenic I(kr) inhibition
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester Medical Center, Rochester, New York, USA
Heart Rhythm 8:1036-43. 2011
..There is a consensus on the limited value of the QTc interval prolongation as a surrogate marker of drug cardiotoxicity and as a risk stratifier in inherited long QT syndrome (LQTS) patients...
Impaired T-amplitude adaptation to heart rate characterizes I(Kr) inhibition in the congenital and acquired forms of the long QT syndromeJean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester Medical Center, Rochester, New York, USA
J Cardiovasc Electrophysiol 18:1299-305. 2007
..In the search for alternative markers, we investigated the T-amplitude and QT interval adaptation to heart rate (HR) in patients with the congenital long QT syndrome (LQTS) and individuals with sotalol-induced QT prolongation...
A quantitative assessment of T-wave morphology in LQT1, LQT2, and healthy individuals based on Holter recording technologyMartino Vaglio
Heart Research Follow Up Program, University of Rochester Medical Center, Rochester, New York, USA
Heart Rhythm 5:11-8. 2008
..The clinical course and the precipitating risk factors in the congenital long QT syndrome (LQTS) are genotype specific...
- Improving the detection of subtle I(Kr)-inhibition: assessing electrocardiographic abnormalities of repolarization induced by moxifloxacin
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester Medical Center, Rochester, New York, USA
Drug Saf 31:249-60. 2008
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- Highly automated QT measurement techniques in 7 thorough QT studies implemented under ICH E14 guidelines
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester Medical Center, Rochester, NY 14642, USA
Ann Noninvasive Electrocardiol 16:13-24. 2011
..1 ± 0.1 ms (P = 0.7). Also, the time course of the moxifloxacin-induced QTc prolongation adjusted for placebo was not statistically different between measurements methods...
- Predictive value of beat-to-beat QT variability index across the continuum of left ventricular dysfunction: competing risks of noncardiac or cardiovascular death and sudden or nonsudden cardiac death
Larisa G Tereshchenko
Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
Circ Arrhythm Electrophysiol 5:719-27. 2012
..The goal of the present study was to determine the predictive value of beat-to-beat QT variability in heart failure patients across the continuum of left ventricular dysfunction...
- Repolarization variability in the risk stratification of MADIT II patients
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology, University of Rochester Medical Center, Rochester, NY 14642, USA
Europace 9:717-23. 2007
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- Improving the precision of QT measurements
Borje Darpo
iCardiac Technologies, 150 Allen Creek Rd, Rochester, NY 14618, USA
Cardiol J 18:401-10. 2011
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- Identification of sotalol-induced changes in repolarization with T wave area-based repolarization duration parameters
Jean Philippe Couderc
Cardiology Unit, Heart Research Follow Up Program, University of Rochester, NY 14642, USA
J Electrocardiol 36:115-20. 2003
..In conclusion, morphological parameters of T wave are able to identify the changes in repolarization interval induced by sotalol. These parameters are more stable and thus more reliable than the traditional QT interval measurements...
- Effects of on-road highway aerosol exposures on autonomic responses in aged, spontaneously hypertensive rats
Alison Elder
Department of Environmental Medicine, University of Rochester, Rochester, New York, USA
Inhal Toxicol 19:1-12. 2007
..These findings show that environmental exposure concentrations of mixed traffic-related UFP/gas-phase emissions can affect the autonomic nervous system...
- Genotype- and Sex-Specific QT-RR Relationship in the Type-1 Long-QT Syndrome
Jean Philippe Couderc
Center for Quantitative Electrocardiography and Cardiac Safety, Heart Research Follow Up Program, University of Rochester Medical Center, NY J P C, X X, A J M, W Z
J Am Heart Assoc 1:e000570. 2012
..We hypothesize that the impaired response to increases in heart rate leads to abnormal QT-RR dynamic profiles and is responsible for the increased cardiac risk for these patients...
- Assessment of the stability of the individual-based correction of QT interval for heart rate
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester, Rochester, New York 14642, USA
Ann Noninvasive Electrocardiol 10:25-34. 2005
..In this study, we propose guidelines to ensure appropriate use of the regression technique for heart rate correction of QT intervals...
- Preserved heart rate variability identifies low-risk patients with nonischemic dilated cardiomyopathy: results from the DEFINITE trial
Eric J Rashba
Division of Cardiology, Department of Medicine, University of Maryland at Baltimore, 22 South Greene Street, Room N3W77, Baltimore, MD 21201, USA
Heart Rhythm 3:281-6. 2006
..The recent expansion of indications for prophylactic implantable cardioverter-defibrillator (ICD) placement in subjects with nonischemic dilated cardiomyopathy has raised concerns about the cost-effectiveness of this therapy...
- Baseline values and sotalol-induced changes of ventricular repolarization duration, heterogeneity, and instability in patients with a history of drug-induced torsades de pointes
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester Medical Center, Rochester, NY 14642, USA
J Clin Pharmacol 49:6-16. 2009
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- A scientific repository to support the research and development of technologies related to quantitative electrocardiography: the Telemetric and Holter ECG Warehouse (THEW)
Jean Philippe Couderc
Center for Quantitative Electrocardiography and Cardiac Safety, University of Rochester Medical Center, Rochester, NY 14618, USA
Cardiol J 17:416-9. 2010
..In this paper, we present briefly the content and the current research triggered by this initiative...
- Investigating the effect of sotalol on the repolarization intervals in healthy young individuals
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, University of Rochester, Rochester, NY, USA
J Electrocardiol 41:595-602. 2008
..In a group of healthy individuals exposed to sotalol, we compared their drug-induced changes to the drug-induced prolongations of the QTc, QTc apex and T-peak to T-end intervals...
- Cardiac regulation and electrocardiographic factors contributing to the measurement of repolarization variability
Jean Philippe Couderc
Heart Research Follow Up Program, Department of Cardiology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA
J Electrocardiol 42:494-9. 2009
..We will discuss these factors and provocatively describe why they should be cautiously considered to avoid erroneous measurements of repolarization instability...
- ECG parameters and exposure to carbon ultrafine particles in young healthy subjects
Wojciech Zareba
Department of Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
Inhal Toxicol 21:223-33. 2009
..However, trends are observed indicating that some subjects might be susceptible to air pollution, with a response involving autonomic modulation of the heart and repolarization of the ventricular myocardium...
- Measure of the QT-RR dynamic coupling in patients with the long QT syndrome
Josef Halamek
Institute of Scientific Instruments, AS CR, Brno, Czech Republic
Ann Noninvasive Electrocardiol 17:323-30. 2012
..The patients with the long QT syndrome type-1 (LQT-1) have an impaired adaptation of the QT interval to heart rate changes. Yet, the description of the dynamic QT-RR coupling in genotyped LQT-1 has never been thoroughly investigated...
- The telemetric and Holter ECG warehouse initiative (THEW): a data repository for the design, implementation and validation of ECG-related technologies
Jean Philippe Couderc
Center for Quantitative Electrocardiography and Cardiac Safety, University of Rochester Medical Center, Rochester, NY 14618, USA
Conf Proc IEEE Eng Med Biol Soc 2010:6252-5. 2010
..We believe that sharing data reinforces open scientific inquiry. It encourages diversity of analysis and opinion while promoting new research and facilitating the education of new researchers...
- A unique digital electrocardiographic repository for the development of quantitative electrocardiography and cardiac safety: the Telemetric and Holter ECG Warehouse (THEW)
Jean Philippe Couderc
Center for Quantitative Electrocardiography and Cardiac Safety, University of Rochester Medical Center, Rochester, NY, USA
J Electrocardiol 43:595-600. 2010
..The THEW hosts unique datasets from clinical trials and drug safety studies that, so far, were not available...
- Measurement and regulation of cardiac ventricular repolarization: from the QT interval to repolarization morphology
Jean Philippe Couderc
Heart Research Follow Up Program, Cardiology Department, Box 653, University of Rochester Medical Center, 601 Elmwood Avenue, University of Rochester, Rochester, NY 14642, USA
Philos Trans A Math Phys Eng Sci 367:1283-99. 2009
..Several modelling techniques and measurement methods will be presented and their role within the arena of cardiac safety will be discussed...
