T-wave morphology differences between patients with and without arrhythmic complication of ischemic heart disease

K Hnatkova1, S J Ryan, J Bathen

  • 1Department of Cardiological Sciences, St. George's Hospital Medical School, London, England. k.hnatkova@sghms.ac.uk

Insights

T-wave morphology analysis using signal-averaged electrocardiograms reveals distinct patterns in patients with myocardial infarction (MI) and ventricular tachycardia/fibrillation (VT/VF). These T-wave descriptors effectively identify arrhythmic complications in ischemic heart disease patients.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Electrocardiography

Background:

  • T-wave abnormalities on electrocardiograms are associated with cardiac arrhythmias.
  • Quantifying T-wave morphology may offer insights into risk stratification for ischemic heart disease patients.

Purpose of the Study:

  • To investigate and compare T-wave morphology using novel quantitative descriptors in healthy individuals, patients post-myocardial infarction (MI), and patients with a history of ventricular tachycardia/fibrillation (VT/VF).
  • To assess the utility of these T-wave descriptors in identifying patients at risk for arrhythmic complications.

Main Methods:

  • Signal-averaged orthogonal electrocardiograms were recorded from 164 healthy controls, 196 MI patients, and 123 VT/VF patients.
  • Two T-wave morphology parameters were calculated: total cosine R to T (global angle) and percentage of loop area (irregularity).
  • Statistical analysis included Mann-Whitney tests and Kruskal-Wallis ANOVA to compare groups.

Main Results:

  • Significant differences in both total cosine R to T and percentage of loop area were observed between all three groups (p < 1.1 x 10(-8)).
  • The parameters demonstrated strong discriminative power, differentiating healthy controls from MI and VT/VF patients, and also distinguishing between MI and VT/VF groups.
  • The two T-wave descriptors were largely uncorrelated, suggesting they capture different aspects of repolarization.

Conclusions:

  • Numerical descriptors of T-wave morphology are powerful indicators of arrhythmic complications in patients with ischemic heart disease.
  • These quantitative measures can effectively differentiate between patients with stable ischemic heart disease and healthy controls.
  • T-wave morphology analysis holds potential for risk stratification in cardiovascular disease management.

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