ABSTRACT
Objective To investigate the electrophysiological characteristics of the atrium in patients with atrial fibrillation (AF) during electrophysiological study (EPS) Methods Seventy two patients with presence of AF during EPS were selected as Group AF , and the other 78 patients without AF as Group control All the patients had no AF history and structural heart diseases P A, P CSd, S1 A1, S2 A2, Max CD, CD zone and ERP HRA were measured as the electrophysiological parameters Results P A, P CSd, S1 A1, S2 A2, Max CD and CD zone were significantly longer in Group AF than in Group control , ERP HRA was shorter in Group AF Conclusion The decreased atrial conduction and the shorter atrial effective refractory period may be the electrophysiological basis for the occurrence of AF