Electrical storm is an independent predictor of adverse long-term outcome in the era of implantable defibrillator therapy.

Aims: Electrical storm (ES) is a life-threatening arrhythmia complication affecting patients treated with an implantable cardioverter defibrillator (ICD). Despite its increasing importance, existing data on prognosis and management of ICD patients affected by ES are limited and conflicting.

Methods: We prospectively studied 169 consecutive patients receiving an ICD.

Differences in the morphology and duration between premature P waves and the preceding sinus complexes in patients with a history of paroxysmal atrial fibrillation.

Background: Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Experimental and human mapping studies have demonstrated that perpetuation of AF is due to the presence of multiple reentrant wavelets with various sizes in the right and left atria.

Hypothesis: Atrial fibrillation may be induced by atrial ectopic beats originating in the pulmonary veins, and premature P-wave (PPW) patterns may help to identify the source of firing.