Change in the atrial activation timing and sequence during narrow QRS tachycardia: What is the mechanism?

Transient changes in QRS morphology during a narrow complex tachycardia: What is the mechanism?

The observation of electrograms and electrocardiograms recorded in sinus rhythm can offer important initial information about the mechanism of arrhythmia. Some patients may have both bundle branch aberrancy or a bystander pathway or multiple pathways, giving rise to varying degrees of QRS fusion. There is need to focus on any change in cycle length of the tachycardia and morphology of QRS during tachycardia. This article is protected by copyright. All rights reserved.

Transition from Two Wide to A Narrow QRS Complex Tachycardia: What is the mechanism of tachycardia and transition?

Spontaneous transition from one tachycardia to another tachycardia poses a challenge to the electrophysiologists and most likely occurs by multiple mechanisms. This article is protected by copyright. All rights reserved.

An interesting response to His-synchronous ventricular stimulation: What is the mechanism of this supraventricular tachycardia?"

Inappropriate therapies are frequent in patients with ICDs and are associated with adverse outcomes, including increased mortality. Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common reentrant narrow complex tachycardia and a cause of inappropriate therapies in these patients. The differential diagnosis of narrow QRS complex tachycardia with ventriculoatrial (VA) dissociation or variable block to the atrium is a pivotal role to avoid inappropriate ICD implantation or then shock therapies. This article is protected by copyright. All rights reserved.