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Estonian Journal of Engineering
Application of novel QT interval correction and QT/RR assessment models to ECG 24-hour recordings in cardiac patients; pp. 107–120
PDF | doi: 10.3176/eng.2010.1.10

Kristi Veski, Deniss Karai, Kristjan Pilt, Kalju Meigas, Jüri Kaik
The aim of the study was to apply different novel ventricular repolarization assessment models to clinical 24-hour ECG recordings for identification of patients with high level of myocardial electrical instability (MEI), i.e. those significantly predisposed to development of potentially life-threatening cardiac arrhythmias. In order to explore the ventricular repolarization inhomogeneity, Holter recordings of forty patients, divided into 4 groups according to their maximal Lown grade (Lown 0, 3A, 4A, 4B), were studied using six QT/RR regression models and six heart rate correction formulas. The algorithm developed during the study enables application of these novel models in routinely registered ECG 24-hour recordings in patients with various heart diseases and without overt heart condition. This approach assures heart rate correction optimization for every single person. The QTc deviation values, obtained with the linear correction model, differed significantly in patients with various MEI levels; thus, if further validated, they can be used as a method for arrhythmia risk stratification

  1. Berger, R. D., Kasper, E. K., Baughman, K. L., Marban, E., Calkins, H. and Tomaselli, G. F. Beat-to-beat QT interval variability: novel evidence for repolarization lability in ischemic and nonischemic dilated cardiomyopathy. Circulation, 1997, 96, 1557–1565.

  2. Hinterseer, M., Thomsen, M. B., Beckmann, B. M., Pfeufer, A., Schimpf, R., Wichmann, H. E., Steinbeck, G. and Kaab, S. J. Beat-to-beat variability of QT intervals is increased in patients with drug-induced long-QT syndrome: a case control pilot study. Eur. Heart J., 2008, 29, 185–190.

  3. Piccirillo, G., Magri, D., Matera, S., Magnanti, M., Torrini, A., Pasquazzi, E., Schifano, E., Velitti, S., Mariglieno, V., Quaglione, R. and Barillà, F. QT variability strongly predicts sudden cardiac death in asymptomatic subjects with mild or moderate left ventricular systolic dysfunction: a prospective study. Eur. Heart J., 2007, 28, 1344–1350.

  4. Haigney, M. C., Zareba, W., Gentlesk, P. J., Goldstein, R. E., Illovski, M., McNitt, S., Andrews, M. L. and Moss, A. J. QT interval variability and spontaneous ventricular tachycardia or fibrillation in MADIT II patients. J. Am. Coll. Cardiol., 2004, 44, 1481–1487.

  5. Nemec, J., Buncova, M., Shusterman, V., Winter, B., Shen, W. K. and Ackerman, M. J. QT interval variability and adaptation to heart rate changes in patients with long QT syndrome. Pacing Clin. Electrophysiol. (PACE), 2009, 32, 72–81.

  6. Lass, J., Kaik, J., Karai, D. and Vainu, M. Ventricular repolarization evaluation from surface ECG for identification of the patients with increased myocardial electrical instability. In Proc. 23rd Annual International Conference of the IEEE, Engineering in Medicine and Biology Society, 2001, vol. 1, 390–393.

  7. Extramiana, F., Maison-Blanche, P., Badilini, F., Pinoteau, J., Deseo, T. and Coumel, P. J. Circadian modulation of QT rate dependence in healthy volunteers: Gender and age differences. J. Electrocardiol., 1999, 32, 33–43.

  8. Malik, M., Färbom, P., Batchvarov, V., Hnatkova, K. and Camm, A. J. Relation between QT and RR intervals is highly individual among healthy subjects: implications for heart rate correction of the QT interval. Heart, 2002, 87, 220–228.

  9. Goldberger, J. J., Cain, M. E., Hohnloser, S. H., Kadish, A. H., Knight, B. P., Lauer, M. S., Maron, B. J., Page, R. L., Passman, R. S., Siscovick, D. et al. American Heart Association/ American College of Cardiology Foundation/Heart Rhythm Society Scientific Statement on Noninvasive Risk Stratification Techniques for Identifying Patients at Risk for Sudden Cardiac Death. A scientific statement from the American Heart Association Council on Clinical Cardiology Committee on Electrocardiography and Arrhythmias and Council on Epidemiology and Prevention. J. Am. Coll. Cardiol., 2008, 52, 1179–1199.

10. Zareba, W., Badilini, F. and Moss, A. J. Automatic detection of heterogeneous repolarization. J. Electrocardiol., 1994, 27, 65–71.

11. Jané, R., Blasi, A., García, J. and Laguna, P. Evaluation of an automatic threshold based detector of waveform limits in holter ECG with the QT database. Comput. Cardiol., 1997, 24, 295–298.
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