Alternans Resonance and Propagation Block during Supernormal Conduction in Cardiac Tissue with Decreased [K+]o
نویسندگان
چکیده
منابع مشابه
Supernormal conduction in cardiac tissue promotes concordant alternans and action potential bunching.
Supernormal conduction (SNC) in excitable cardiac tissue refers to an increase of pulse (or action potential) velocity with decreasing distance to the preceding pulse. Here we employ a simple ionic model to study the effect of SNC on the propagation of action potentials (APs) and the phenomenology of alternans in excitable cardiac tissue. We use bifurcation analysis and simulations to study att...
متن کاملSupernormal Conduction and Suppression of Spatially Discordant Alternans of Cardiac Action Potentials
Spatially discordant alternans (DA) of action potential durations (APD) is thought to be more pro-arrhythmic than concordant alternans. Super normal conduction (SNC) has been reported to suppress formation of DA. An increase in conduction velocity (CV) as activation rate increases, i.e., a negative CV restitution, is widely considered as hallmark of SNC. Our aim in this study is to show that it...
متن کاملReverse Wenckebach “pseudo-supernormal” conduction or paroxysmal atrioventricular block
Paroxysmal atrioventricular-block is a poorly-recognized cause of atrioventricular conduction abnormality leading to syncope and can be fatal. Here we report a case of paroxysmal atrioventricular-block presenting as syncope treated effectively with pacemaker implantation and review the current literature on prevalence, known mechanisms and treatment for it. Importantly we provide the diagnostic...
متن کاملSupernormal phase of AV conduction. A study during heart block and endocardial pacing.
A distinct, well-defined phase has been identified in a patient with heart block during which sinus impulses were conducted to the ventricles. This phase persisted during pacing but its onset and termination were delayed. No significant difference was found at varying pacing rates. On four occasions while pacing, two consecutive sinus impulses were conducted to the ventricles but this was not s...
متن کاملConcealed and supernormal atrioventricular conduction.
THE FAILURE of a cardiac impulse to traverse the entire atrioventricular (AV) conducting system is called concealed conduction. Electrocardiographically, the effects of concealed conduction are reflected in the conduction and/or formation of subsequent beats.1 The concept of concealed conduction can be applied to explain (1) post-extrasystolic prolongation of the P-R interval, (2) the irregular...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2010
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2009.12.4280