ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
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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

Full article in PDF format | doi: 10.3176/eng.2010.1.10

Authors
Kristi Veski, Deniss Karai, Kristjan Pilt, Kalju Meigas, Jüri Kaik

Abstract
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
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