BACKGROUND Syncope in patients with supraventricular tachycardia has been suggested to be an ominous finding, predictive of rapid rates during tachycardia. METHODS AND RESULTS To explore the mechanism of syncope during supraventricular tachycardia, tachycardia was induced in the supine position and after passive head-up tilting to 60 degrees in 13 patients with atrioventricular (AV) node reen...

the aim of this study is to evaluate how far lempel-ziv complexity (lzc) of the binary symbolic sequences resulting from static or dynamic transformation (partitioning first-order difference) of the short-term electrocardiogram (ecg) signals (only 2 seconds duration) has the  potential in discriminating normal and ventricular tachycardia/ventricular fibrillation (vt/vf) subjects. the statistica...

We have developed a microcomputer algorithm for tachycardia identification suitable for use in an implanted antitachycardia pacemaker. The algorithm distinguishes atrial, ventricular, and AV reentrant tachycardia, while ignoring high rates due to sinus tachycardia. A new method whereby the pacemaker delivers an atrial extrastimulus has been developed for distinguishing paroxysmal 1:1 tachycardi...

OBJECTIVE The purpose of this study was to determine if the atrial response upon cessation of ventricular pacing associated with 1:1 ventriculoatrial conduction during paroxysmal supraventricular tachycardia is a useful diagnostic maneuver in the electrophysiology laboratory. BACKGROUND Despite various maneuvers, it can be difficult to differentiate atrial tachycardia from other forms of paro...

A 25-year-old woman with a 5-year history of paroxysmal supraventricular tachycardia underwent an electrophysiologic procedure. The baseline sinus cycle length, atrial–His-bundle (AH) interval, and His-bundle–ventricular (HV) interval were 750, 60, and 50 msec, respectively. Paroxysmal supraventricular tachycardia with a cycle length of 320 msec was induced by programmed atrial stimulation with...

Double tachycardia is a relatively rare condition. We describe a 21 year old woman with history of frequent palpitations. In one of these episodes, she had wide complex tachycardia with right bundle branch and inferior axis morphology. A typical atrioventricular nodal tachycardia was induced during electrophysiologic study, aimed at induction of clinically documented tachycardia. Initially no v...

Fifty patients with sustained ventricular tachycardia were studied by endocavitary recordings and programmed electrical stimulation. Of 29 patients in whom tachycardia could be initiated, 18 had chronic coronary artery disease and eight had no detectable heart disease. Of 35 patients in whom the tachycardia could be terminated by premature ventricular stimuli, 21 had chronic coronary artery dis...

A total of 99 consecutive 24-hour Holter recordings with ventricular tachycardia were reviewed. Ventricular premature beats which occurred alone, and ventricular premature beats which initiated ventricular tachycardia were examined to determine which characteristics correlated with occurrence of ventricular tachycardia and which predicted rate and duration of ventricular tachycardia. The preced...

A 42-year-old woman was referred for radiofrequency catheter ablation of narrow QRS tachycardia that was terminated with intravenous adenosine. Baseline twelve-lead ECG was normal during sinus rhythm and transthoracic echocardiography demonstrated no evidence of structural heart disease. The electrophysiological study showed a normal AH interval of 114 ms and HV interval of 37 ms during sinus r...

AIMS The aim of this study was to compare cardiac autonomic regulation in patients with a history of paroxysmal supraventricular tachyarrhythmias, such as atrioventricular nodal reentrant tachycardia and atrioventricular reentrant tachycardia, and healthy controls. METHODS AND RESULTS Seventeen patients with paroxysmal atrioventricular nodal reentrant tachycardia (atrioventricular nodal reent...