In a normal human life span, the heart beats about 2–3 billion times. Under diseased
conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster …

Defining the cellular electrophysiological mechanisms for ventricular tachyarrhythmias is
difficult, given the wide array of potential mechanisms, ranging from abnormal automaticity to …

Rationale: Alternans is a risk factor for cardiac arrhythmia, including atrial fibrillation. At the
cellular level alternans manifests as beat-to-beat alternations in contraction, action potential …

Background The relation between myocardial scar and different types of ventricular
arrhythmias in patients with nonischemic dilated cardiomyopathy (NIDCM) is unknown …

Initiation of reentry requires 2 factors:(1) a triggering event, most commonly focal excitations
such as premature ventricular complexes (PVCs); and (2) a vulnerable substrate with …

In cardiac patients, life‐threatening tachyarrhythmia is often precipitated by abnormal
changes in ventricular repolarization and refractoriness. Repolarization abnormalities …

During temperature‐controlled radiofrequency (RF) ablation a popping sound sometimes
occurs. This popping phenomenon is known to be associated with unwanted effects like …

Background The restitution of the action potential duration (APDR) and conduction velocity
(CVR) are mechanisms whereby cardiac excitation and repolarization adapt to changes in …

Atrial fibrillation is the most common sustained arrhythmia and its prevalence is rapidly rising
with the aging of the population. Cardiac alternans, defined as cyclic beat-to-beat …

A beat-to-beat alternation in the action potential duration (APD) of myocytes, ie alternans, is
believed to be a direct precursor of ventricular fibrillation in the whole heart. A common …