AIMS This study aimed to clarify the safety and efficacy of selective fast pathway ablation in patients with atrioventricular nodal reentrant tachycardia and a prolonged PR interval during sinus rhythm. Such patients have been reported to have an increased incidence of complete atrioventricular block. METHODS AND RESULTS In this study, the earliest retrograde atrial activation during atrioven...

OBJECTIVES We investigated the safety and efficacy of cryoablation in the treatment of pediatric patients with accessory pathways (APs) located near the atrioventricular junction and with atrioventricular nodal re-entrant tachycardia (AVNRT). BACKGROUND Few studies concern cryoablation in a significant number of pediatric patients involving treatment for supraventricular tachycardias (SVTs) w...

Overexpression of a truncated Kv1.1 or Kv2.1 channel polypeptide in the heart (Kv1DN or Kv2DN) resulted in mice with a prolonged action potential duration (APD) due to marked attenuation of rapidly activating, slowly inactivating K+ current (I(K,slow1)) or slowly inactivating outward K(+) current (I(K,slow2)) in ventricular myocytes. ECG monitoring, optical mapping, and programmed electrical st...

INTRODUCTION Standard electrophysiologic techniques generally allow discrimination among mechanisms of paroxysmal supraventricular tachycardia. The purpose of this study was to determine whether the response of paroxysmal supraventricular tachycardia to atrial and ventricular overdrive pacing can help determine the tachycardia mechanism. METHODS AND RESULTS Fifty-three patients with paroxysma...

Myocardial fibrosis increases arrhythmia vulnerability of the diseased heart. The renin-angiotensin-aldosterone system (RAAS) governs myocardial collagen synthesis. We hypothesized that reducing cardiac fibrosis by chronic RAAS inhibition would result in reduced arrhythmia vulnerability of the senescent mouse heart. Wild-type mice (52 wk old) were treated for 36 wk: 1) untreated control (C); 2)...

Transvenous radiofrequency catheter ablation (RFA) for treatment of atrioventricular (AV) reentrant tachycardia and AV nodal reentrant tachycardia is remarkably successful. To the best of my knowledge, there has not been a large randomized trial comparing RFA with other treatments for these tachycardias. The lack of such trials is due at least in part to the self-evident efficacy of RFA in this...

Wave propagation around various geometric expansions, structures, and obstacles in cardiac tissue may result in the formation of unidirectional block of wave propagation and the onset of reentrant arrhythmias in the heart. Therefore, we investigated the conditions under which reentrant spiral waves can be generated by high-frequency stimulation at sharp-edged obstacles in the ten Tusscher-Noble...

A 13 year old boy had a wide QRS complex tachycardia. A discontinuity in the AV nodal functional curve was observed in the electrophysiologic study. The AV internal was prolonged in association with progressive ventricular preexcitation. At maximal preexcitation, the HV interval was -20 msec and the QRS complex was identical to that seen during clinical tachycardia. No VA conduction was found a...

BACKGROUND Longitudinal dissociation of an anatomic pathway into 2 electrophysiologically distinct pathways has been hypothesized as a basis for localized AV nodal reentry and supraventricular arrhythmias. METHODS AND RESULTS Extracellular bipolar and intracellular microelectrodes were used to record activation in the superfused rabbit AV junction. A subset of rabbit hearts (n=19 of 72) demon...

BACKGROUND Recent anatomical and electrophysiological studies have demonstrated that in the human atrioventricular node there are two main extensions, the rightward and leftward posterior nodal extension (LPNE). The occurrence of eccentric retrograde atrial activation has been demonstrated in several previous reports to be from 6 to 8% in patients with AVNRT. OBJECTIVES The study was performe...