Your Search Results

Use this resource - and many more! - in your textbook!

AcademicPub holds over eight million pieces of educational content for you to mix-and-match your way.

Experience the freedom of customizing your course pack with AcademicPub!
Not an educator but still interested in using this content? No problem! Visit our provider's page to contact the publisher and get permission directly.

An Estimate of the Dispersion of Repolarization Times Based on a Biophysical Model of the ECG

By: Mainardi, L.T.; Sassi, R.;

2011 / IEEE


This item was taken from the IEEE Periodical ' An Estimate of the Dispersion of Repolarization Times Based on a Biophysical Model of the ECG ' Temporal heterogeneity of ventricular repolarization is a key quantity for the development of ventricular reentrant arrhythmia. In this paper, we introduce the -index, a novel ECG-based estimator of the standard deviation of ventricular myocytes' repolarization times . Differently from other ECG metrics of repolarization heterogeneity, the -index was derived from the analysis of a biophysical model of the ECG, where repolarization is described by the dominant T-wave (DTW) paradigm. The model explains the shape of T-waves in each lead as a projection of a main waveform (the DTW) and its derivatives weighted by scalars, the lead factors. A mathematical formula is derived to link the heterogeneity of ventricular repolarization and the V-index. The formula was verified using synthetic 12-lead ECGs generated with a direct electrophysiological model for increasing values of s (in the range 20-70 ms). A linear relationship between the V-index and s was observed, VH 0.675 s + 1.8 ms (R2=0.9992). Finally, 68 ECGs from the E-OTH-12-0068-010 database of the Telemetric and Holter ECG Warehouse were analyzed. The -index coherently increased after sotalol administration, a drug known to have QT-prolonging potential (p j 0.001).