1. Department of Electrophysiology, University Heart Center Hamburg; University Hospital Hamburg Eppendorf; Hamburg Germany
2. Department of Cardiology II/Electrophysiology, Center of Cardiology, University Medical Center; Johannes Gutenberg-University Mainz; Germany
3. Department of Electrophysiology; University Hospital Cologne; Germany
4. Department of Electrophysiology; Hirslanden Hospital; Zurich Switzerland