Identifying Reentrant Arrhythmias
نویسنده
چکیده
We studied transient entrainment and interruption of atrioventricular (AV) bypass pathway-type paroxysmal atrial tachycardia in 15 patients during overdrive pacing from selected atrial sites. Overdrive atrial pacing at less than a critically rapid rate for interruption transiently entrained the tachycardia. Transient entrainment was due to repeated early entrance of the wave front from the pacing impulse into the reentry loop in both antidromic and orthodromic directions. The antidromic wave front of each pacing impulse was repeatedly blocked as it collided with the orthodromic wave front of the previous beat, in effect extinguishing the tachycardia. However, the early entrance of the orthodromic wave front of each pacing impulse repeatedly reset the tachycardia. The result was that during transient entrainment, the tachycardia rate increased to the pacing rate. Interruption of the tachycardia occurred when overdrive pacing produced block within the reentry loop of both the antidromic and orthodromic wave fronts of the
منابع مشابه
Clinical and electrophysiological characteristics in patients with atrioventricular reentrant and atrioventricular nodal reentrant tachycardia.
AIM To compare clinical, electrophysiological characteristics and transcatheter ablation results between two groups of patients, one with atrioventricular reentrant tachycardia (AVRT) and the other with atrioventricular nodal reentrant tachycardia (AVNRT). METHODS The study population consisted of 94 consecutive patients who underwent endocavitary electrophysiological study and radiofrequency...
متن کاملIslands of spatially discordant APD alternans underlie arrhythmogenesis by promoting electrotonic dyssynchrony in models of fibrotic rat ventricular myocardium
Fibrosis and altered gap junctional coupling are key features of ventricular remodelling and are associated with abnormal electrical impulse generation and propagation. Such abnormalities predispose to reentrant electrical activity in the heart. In the absence of tissue heterogeneity, high-frequency impulse generation can also induce dynamic electrical instabilities leading to reentrant arrhyth...
متن کاملGeneration of reentrant arrhythmias by dominant-negative inhibition of connexin43 in rat cultured myocyte monolayers.
AIMS Alteration of connexin43 (Cx43)-mediated intercellular communication is known to promote susceptibility to ventricular tachyarrhythmias. However, the precise mechanism of the altered Cx43 responsible for arrhythmogenesis remains unclear. We sought to understand changes in impulse propagation of ventricular myocytes under dominant-negative (DN) inhibition of Cx43 in the development of arrhy...
متن کاملArrhythmia/Electrophysiology Risk of Malignant Arrhythmias in Initially Symptomatic Patients With Wolff-Parkinson-White Syndrome Results of a Prospective Long-Term Electrophysiological Follow-Up Study
Background—The available amount of detailed long-term data in patients with Wolff-Parkinson-White syndrome is limited, and no prospective electrophysiological studies looking at predictors of malignant arrhythmia are available. Methods and Results—Among 8575 symptomatic Wolff-Parkinson-White patients with atrioventricular reentrant tachycardia referred for electrophysiological test, 369 (mean a...
متن کاملEnhanced dispersion of repolarization and refractoriness in transgenic mouse hearts promotes reentrant ventricular tachycardia.
The heterogeneous distribution of ion channels in ventricular muscle gives rise to spatial variations in action potential (AP) duration (APD) and contributes to the repolarization sequence in healthy hearts. It has been proposed that enhanced dispersion of repolarization may underlie arrhythmias in diseases with markedly different causes. We engineered dominant negative transgenic mice that hav...
متن کاملAssessing the atrial electromechanical coupling during atrial focal tachycardia, flutter, and fibrillation using electromechanical wave imaging in humans
Minimally-invasive treatments of cardiac arrhythmias such as radio-frequency ablation are gradually gaining importance in clinical practice but still lack a noninvasive imaging modality which provides insight into the source or focus of an arrhythmia. Cardiac deformations imaged at high temporal and spatial resolution can be used to elucidate the electrical activation sequence in normal and pac...
متن کامل