1. Division of Cardiology, Innsbruck Medical University, Innsbruck, Austria
2. Department of Medical Statistics, Informatics and Health Economics, Innsbruck Medical University, Innsbruck, Austria
3. Division of Cardiology, Innsbruck Medical University, Anichstrasse 35, A-6020 Innsbruck, Austria. Tel: +43 512 504 23406; Fax: +43 512 504 22767;