Repolarization Alternans

Repolarization alternans: toward a unifying theory of reentrant arrhythmia induction.

The appearance of electrocardiographic T-wave alternans with elevated heart rate or metabolic insult has been observed for nearly a century.1 Macroscopic T-wave alternans is often noted as a harbinger of sudden arrhythmic death.2 Efforts to quantify the magnitude of more subtle repolarization alternans and relate these measurements to arrhythmia susceptibility have been pursued since the 1980s....

Discordant repolarization alternans-induced atrial fibrillation is suppressed by verapamil.

BACKGROUND Ventricular alternans of repolarization produces serious ventricular arrhythmias in experimental models. The present study investigated the role of alternans of atrial repolarization in patients with atrial fibrillation (AF). METHODS AND RESULTS Electrophysiological studies were performed in 19 patients without structural heart disease. Monophasic action potentials (MAP) were recor...

Characterization of Repolarization Alternans in the Coronary Artery Disease

Arrhythmia/Electrophysiology Repolarization Alternans Reveals Vulnerability to Human Atrial Fibrillation

Background—The substrates for human atrial fibrillation (AF) are poorly understood, but involve abnormal repolarization (action potential duration [APD]). We hypothesized that beat-to-beat oscillations in APD may explain AF substrates, and why vulnerability to AF forms a spectrum from control subjects without AF to patients with paroxysmal then persistent AF. Methods and Results—In 33 subjects ...

Repolarization alternans reveals vulnerability to human atrial fibrillation.

BACKGROUND The substrates for human atrial fibrillation (AF) are poorly understood, but involve abnormal repolarization (action potential duration [APD]). We hypothesized that beat-to-beat oscillations in APD may explain AF substrates, and why vulnerability to AF forms a spectrum from control subjects without AF to patients with paroxysmal then persistent AF. METHODS AND RESULTS In 33 subject...