Repolarization Alternans in Dilated Pulsing Atria

Characterization of Repolarization Alternans in the Coronary Artery Disease

Myocardial cell death in fibrillating and dilated human right atria.

OBJECTIVES The aim of the present study was to determine if myocytes can die by apoptosis in fibrillating and dilated human atria. BACKGROUND The cellular remodeling that occurs during atrial fibrillation (AF) may reflect a degree of dedifferentiation of the atrial myocardium, a process that may be reversible. METHODS We examined human right atrial myocardium specimens (n = 50) for the pres...

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...

Alternans of blood pressure and heart rate in dilated cardiomyopathy.

Impaired myocardial performance is known to be associated with electrical and mechanical beat-to-beat alternans phenomena. The alternans in blood pressure and heart rate and their interdependency in idiopathic dilated cardiomyopathy (IDC) were studied. The arterial blood pressure and the electrocardiograph (ECG) were continuously recorded in 22 patients suffering from IDC (age 49 +/- 13 years, ...