Homogenization of Atrial Electrical Activities: Conceptual Restoration of Regional Electrophysiological Parameters to Deter Ischemia-Dependent Conflictogenic Atrial Fibrillation.
نویسنده
چکیده
Atrial fibrillation (AF) as a severe arrhythmia is now spreading worldwide at overwhelmingly high rates, particularly in elderly patients. Despite new insights, the mechanisms underlying AF are not conclusively determined yet. Taking into account the ischemic origin of arrhythmia induction (according to the so-called conflictogenic atrial fibrillation, declared recently) restoration of regional electrophysiological parameters is essential in tackling AF. We hypothesized that some atrial electrophysiological parameters, preferably the effective refractory period, might need to be controlled to prevent AF. All the remaining parameters - conduction velocity, conduction time, recovery time, vulnerability, excitability, repolarization etc. being as if secondary and less important could be ignored. Homogenization of the milieu producing AF might be implemented, at least theoretically, through restoration of blood supply in ischemic areas and/or via attenuation of electrophysiological differences between conflicting regions by delivery of atrial sub-threshold non-captured pulse-trains. Adjunctive therapy by drugs containing vasodilatory features and affecting the effective refractory period appears to be fundamental. Thus, stabilization of disorganized atrial cellular activities likely may lead to the recovery of atrial excitable characteristics. Despite the lack of compelling evidence, the application of the concept may be helpful in order to search for more precise and more effective methods to favorably change the refractory period. Further studies are necessary to determine whether restoration or improvement of blood circulation of atrial wall is feasible. Based on such considerations a novel preventive AF strategies are to be designed.
منابع مشابه
Modulation of extracellular atrioventricular node field potential pattern and ventricular rhythm by morphine in experimental atrial fibrillation in isolated rabbit heart
Introduction: Endorphins are produced by cardiomyocytes, and exert different effects on the heart. The aim of the present study is to assess morphine effects on extracellular atrioventricular (AV) node field potential pattern and ventricular rhythm of isolated rabbit heart during experimental atrial fibrillation (AF). Methods: Effects of different concentrations of morphine (10, 20, 50 and 1...
متن کاملNew manifestations of electrophysiological remodeling of heart during experimental model of atrial fibrillation in cirrhotic rat isolated heart
Introduction: The present study is aimed to evaluate electrophysiological remodeling of atrioventricular (AV) node and ventricular conduction during experimental atrial fibrillation (AF) model in isolated heart of cirrhotic rats. Methods: Cirrhosis-induced electrophysiological remodeling was evaluated in 24 isolated retrogradely perfused rat hearts in 2 groups (control and cirrhotic). Cirrho...
متن کاملEffects Of Fast Pathway Ablation On The Concealment Zone And Electrophysiological Behavior Of AV-Node During Atrial Fibrillation.
Objectives: Dual pathways have a determinant role in the occurrence of atrio nodal tachyarrhythmia (AVNRT). The aim of present study is to determine the role of slow pathway (SP) in the concealment zone and protective role of AV node during atrial fibrillation (AF). Material &Methods: In 7 isolated nodal rabbit preparation zone of concealment and concealed conduction is quantified by Specif...
متن کاملRole of nitric oxide on the electrophysiological properties of isolated rabbit atrioventricular node by extracellular field potential during atrial fibrillation
Introduction: The aim of the present study was to determine direct effects of NO modulation on protective electrophysiological properties of atrioventricular node (AV node) in the experimental model of AF in rabbit. Methods: Isolated perfused rabbit AV nodal preparations were used in two groups. In the first group (N=7), LNAME (50μM) was applied. In the second group (N=12), different concent...
متن کاملCardiac Events Theoretically Cannot Be Produced By Non-Ischemic And/Or Iso-Ischemic Myocardium: Challenging Postulations And Vitality Of The Concept Of "Ischemia-Dependent Conflictogenic Arrhythmias".
Ischemia plays a key role in cardiac arrhythmogenesis, particularly in elderly patients. Healthy, non-ischemic and structurally normal myocardium is universally free from dysrhythmias. Thereby intact coronary blood flow prevents potential cardiac events. Hypothetically, ischemia-related electrophysiological differences are responsible for the supraventricular and/or ventricular rhythm 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
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of atrial fibrillation
دوره 6 2 شماره
صفحات -
تاریخ انتشار 2013