Albert Feeny1, Larisa G Tereshchenko2. 1. Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, USA. 2. The Division of Cardiology, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD, USA; The Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA. Electronic address: tereshch@ohsu.edu.
Abstract
BACKGROUND: The goal of this study was to compare the time series predictors of beat-to-beat variability in repolarization in healthy individuals. METHODS: Spatial QRS- and T-vector amplitudes, spatial QRS-T, RR' and TT' angles, RR' and QT intervals, and QRS- and T-loop roundness were measured on 453 consecutive sinus beats in 168 healthy subjects (mean age 39.8±15.6years; 50% men; 93% white). Panel time-series regression models were adjusted by age, sex, and race. Appropriate time series of ECG metrics served as predictors and outcomes. RESULTS: Increase in T-loop roundness index by 0.1 was associated with 1.1° (95%CI 0.9-2.2; P=0.048) increase in corresponding TT' angle. One unit increase in a respiration index was associated with 4ms (95%CI 0.6-7.0; P=0.021) increase in QT interval. CONCLUSIONS: Spatial TT' angle and beat-to-beat variability in T-loop roundness represent intrinsic measures of repolarization variability. QT interval variability characterizes the effect of respiration and heart rate variability.
BACKGROUND: The goal of this study was to compare the time series predictors of beat-to-beat variability in repolarization in healthy individuals. METHODS: Spatial QRS- and T-vector amplitudes, spatial QRS-T, RR' and TT' angles, RR' and QT intervals, and QRS- and T-loop roundness were measured on 453 consecutive sinus beats in 168 healthy subjects (mean age 39.8±15.6years; 50% men; 93% white). Panel time-series regression models were adjusted by age, sex, and race. Appropriate time series of ECG metrics served as predictors and outcomes. RESULTS: Increase in T-loop roundness index by 0.1 was associated with 1.1° (95%CI 0.9-2.2; P=0.048) increase in corresponding TT' angle. One unit increase in a respiration index was associated with 4ms (95%CI 0.6-7.0; P=0.021) increase in QT interval. CONCLUSIONS: Spatial TT' angle and beat-to-beat variability in T-loop roundness represent intrinsic measures of repolarization variability. QT interval variability characterizes the effect of respiration and heart rate variability.
Authors: Esther Pueyo; Alberto Corrias; László Virág; Norbert Jost; Tamás Szél; András Varró; Norbert Szentandrássy; Péter P Nánási; Kevin Burrage; Blanca Rodríguez Journal: Biophys J Date: 2011-12-20 Impact factor: 4.033
Authors: Larisa G Tereshchenko; Lichy Han; Alan Cheng; Joseph E Marine; David D Spragg; Sunil Sinha; Darshan Dalal; Hugh Calkins; Gordon F Tomaselli; Ronald D Berger Journal: Heart Rhythm Date: 2010-09-29 Impact factor: 6.343
Authors: Andrew Oehler; Trevor Feldman; Charles A Henrikson; Larisa G Tereshchenko Journal: Ann Noninvasive Electrocardiol Date: 2014-09-09 Impact factor: 1.468
Authors: Jordi Heijman; Antonio Zaza; Daniel M Johnson; Yoram Rudy; Ralf L M Peeters; Paul G A Volders; Ronald L Westra Journal: PLoS Comput Biol Date: 2013-08-22 Impact factor: 4.475
Authors: Lichy Han; Alan Cheng; Sanjoli Sur; Gordon F Tomaselli; Ronald D Berger; Larisa G Tereshchenko Journal: Int J Cardiol Date: 2012-10-18 Impact factor: 4.164