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A Principal Component Regression Approach for Estimating Ventricular Repolarization Duration Variability


Ventricular repolarization duration (VRD) is affected by heart rate and autonomic control, and thus VRD varies in time in a similar way as heart rate. VRD variability is commonly assessed by determining the time differences between successive R- and T-waves, that is, RT intervals. Traditional methods for RT interval detection necessitate the detection of either T-wave apexes or offsets. In this paper, we propose a principal-component-regression- (PCR-) based method for estimating RT variability. The main benefit of the method is that it does not necessitate T-wave detection. The proposed method is compared with traditional RT interval measures, and as a result, it is observed to estimate RT variability accurately and to be less sensitive to noise than the traditional methods. As a specific application, the method is applied to exercise electrocardiogram (ECG) recordings.


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Correspondence to Mika P. Tarvainen.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Tarvainen, M.P., Laitinen, T., Lyyra-Laitinen, T. et al. A Principal Component Regression Approach for Estimating Ventricular Repolarization Duration Variability. EURASIP J. Adv. Signal Process. 2007, 058358 (2007).

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