14th International Congress
THE "NEW FRONTIERS"
OF ARRHYTHMIAS 2000

Jan. 29 - Feb. 5, 2000
Marilleva, Trento, Italy

RT-159

The electrophysiologic substrate in patients with idiopathic atrial fibrillation

Richard N.W. Hauer, Hemanth Ramanna.
Heart-Lung Institute, University Medical Centre, Utrecht, The Netherlands

Introduction

The occurrence of atrial fibrillation depends on multiple factors. A trigger is needed for the onset of the arrhythmia. Artificially, rapid pacing is such a trigger, or programmed electrical stimulation by extra stimuli, as used in electrophysiologic studies. Very recently, rapid atrial firing predominantly in the pulmonary veins, have been described as a natural trigger^1,2. The second factor is the substrate. A substrate may be due to structural heart disease or the remodeling process, due to long lasting atrial fibrillation. Remodeling has been described by Wijffels et al., presenting their results in an experimental model³. This remodeling process has been described in goats as “atrial fibrillation begets atrial fibrillation”. However, atrial fibrillation may occur without structural heart disease and without previous remodeling. In that situation, an initiating substrate is needed. This electrophysiologic substrate was studied in patients with idiopathic atrial fibrillation.