Electrophysiological Mechanisms Underlying T-Wave Alternans and Their Role in Arrhythmogenesis

Front Physiol. 2021 Mar 4:12:614946. doi: 10.3389/fphys.2021.614946. eCollection 2021.


T-wave alternans (TWA) reflects every-other-beat alterations in the morphology of the electrocardiogram ST segment or T wave in the setting of a constant heart rate, hence, in the absence of heart rate variability. It is believed to be associated with the dispersion of repolarization and has been used as a non-invasive marker for predicting the risk of malignant cardiac arrhythmias and sudden cardiac death as numerous studies have shown. This review aims to provide up-to-date review on both experimental and simulation studies in elucidating possible mechanisms underlying the genesis of TWA at the cellular level, as well as the genesis of spatially concordant/discordant alternans at the tissue level, and their transition to cardiac arrhythmia. Recent progress and future perspectives in antiarrhythmic therapies associated with TWA are also discussed.

Keywords: T-wave alternans; arrhythmia; simulation; spatial discordant alternans; sudden cardiac death.

Publication types

  • Review