A randomized study to compare ramp versus burst antitachycardia pacing therapies to treat fast ventricular tachyarrhythmias in patients with implantable cardioverter defibrillators: the PITAGORA ICD trial.

Background: In patients with implantable cardioverter-defibrillators (ICDs), antitachycardia pacing (ATP) is highly effective in terminating fast ventricular tachycardias (FVTs) and lowers the use of high-energy shocks, without increasing the risk of arrhythmia acceleration or syncope.

Methods And Results: The aim of the PITAGORA ICD trial was to randomly compare 2 ATP strategies (88% coupling interval burst versus 91% coupling interval ramp, both 8 pulses) in terms of ATP efficacy, arrhythmia acceleration, and syncope. Two hundred six ICD patients (83% male, 67+/-11 years) were enrolled.

Transesophageal low-energy cardioversion of atrial fibrillation without fluoroscopy outside the electrophysiology laboratory.

Background: Low-energy internal cardioversion (LEIC) is a safe and effective procedure for the restoration of sinus rhythm in patients with atrial fibrillation refractory to external cardioversion. However, the procedure needs fluoroscopy and the use of the electrophysiology laboratory, even when the esophageal approach is utilized. The aim of this study was to assess the efficacy, safety and tolerability of a new simplified procedure of esophageal LEIC performed without fluoroscopy, outside the electrophysiology laboratory.

Postcardioversion atrial electrophysiologic changes induced by oral verapamil in patients with persistent atrial fibrillation.

Objectives: The aim of our study was to verify the effect of oral administration of verapamil on atrial electrophysiologic characteristics after cardioversion of persistent atrial fibrillation (AF) in humans.

Background: Discordant findings have been reported regarding the efficacy of verapamil in preventing the electrical remodeling induced by AF.

Methods: We determined the effective refractory periods (ERPs) at five pacing cycle lengths (300 to 700 ms) and in five right atrial sites after internal cardioversion of persistent AF (mean duration 238.

Single shock endocavitary low energy intracardiac cardioversion of chronic atrial fibrillation.

Background: Discomfort related to low-energy internal cardioversion (LEIC) represents a real problem in patients (pts) with atrial fibrillation (AF). The aim of our study was to verify if a single shock could restore sinus rhythm (SR) with a lower discomfort for the pt.

Methods: Thirty pts with chronic AF were randomized to receive a single 350 V shock (15 pts) or multiple shocks of increasing energy (15 pts).

Spatial extension of local pacing capture in the lateral free wall of the right atrium during clinical chronic atrial fibrillation.

Objectives: The aims of our study were to define the spatial extension of local atrial pacing capture (LAPC) in the right lateral atrial wall and to verify the effects of antiarrhythmic drugs on capture extension.

Background: Recently, LAPC during spontaneous chronic atrial fibrillation (AF) has been demonstrated directly in humans, but no systematic attempt has been made to evaluate its spatial extension.

Methods: The study was conducted in 14 consecutive patients with chronic AF, nine of whom were taking antiarrhythmic drugs.