BACKGROUND The basis of the unique effectiveness of amiodarone for atrial fibrillation (AF) is poorly understood. The present study tested the hypothesis that amiodarone blocks electrical remodeling induced by atrial tachycardia. METHODS AND RESULTS Mongrel dogs were subjected to atrial tachycardia (400 bpm for 7 days) in the absence and presence of therapy with amiodarone, the class III card...

Junctional ectopic tachycardia has been described in infants but not in adults. Five adults with rapid symptomatic paroxysmal junctional tachycardia, distinct from the more common slower nonparoxysmal junctional tachycardia, were recently evaluated. The tachycardia was irregular (rate 120 to 250) and accompanied by periods of atrioventricular dissociation and narrow QRS complexes. A junctional ...

OBJECTIVES This study was performed to determine the incidence of symptomatic, sustained atrial fibrillation in a group of patients with paroxysmal supraventricular tachycardia. The effects of the mechanism of paroxysmal supraventricular tachycardia (atrioventricular [AV] node reentry vs. AV reentry through an accessory pathway) and heart rate during the tachycardia on the occurrence of atrial ...

Atrial tachycardia is defined as a regular atrial activation from atrial areas with centrifugal spread, caused by enhanced automaticity, triggered activity or microreentry. New ECG classification differentiates between focal and macroreentrant atrial tachycardia. Macroreentrant atrial tachycardias include typical atrial flutter and other well characterized macroreentrant circuits in right and l...

In 10 patients, 24 episodes of supraventricular tachycardia were treated by rapid electrical stimulation of the right atrium. One episode of sinus tachycardia, eight episodes of atrial tachycardia, two episodes of atrial flutter, and 13 episodes of A-V junctional tachycardia occurred. In each case the diagnosis of the arrhythmia was documented by obtaining unipolar and bipolar intra-atrial elec...

A 46-year-old male was admitted to our emergency department due to a narrow QRS tachycardia of 230 bpm with impeding hemodynamic collapse. His only remarkable medical history was mild hypertension. Adenosine administration was ineffective in stopping the tachycardia, and sinus rhythm was restored using an electrical cardioversion. A few weeks later, during an electrophysiology study an identica...

THE INTRODUCTION of the adrenergic beta-receptor blocking agent, pronethalol,1 and the more recent availability of its analogue propranolol2 have served as a new impetus in the pharmacological study of the cardiovascular system. Clinical use of these compounds has been explored in the treatment of hypertension,3 angina pectoris,4 prolonged systemic hypotension,5 hypertrophic subaortic stenosis,...

Rev Esp Cardiol 2003;56(4):331-2 331 Today the majority of tachyarrhythmias can be treated with percutaneous ablation.1 To summarize, the ablation procedure consists of transmitting energy (generally radiofrequency) to the distal electrode of a catheter introduced into the heart via a vein or artery. This electrode, once placed at the site chosen by means of electroanatomic references, selectiv...

I read with interest the article by David et al. regarding a case of recurrent tachycardia-induced cardiomyopathy secondary to typical atrial flutter. I have some concerns regarding the management of the recurrences of atrial flutter and tachycardiainduced cardiomyopathy in this case. The authors’ choice of treatment involved DC cardioversion of the atrial flutter that was successful in restori...