[1] Univ Basel Hosp, Dept Med, CH-4031 Basel, Switzerland
[2] Univ Basel Hosp, Div Cardiol, CH-4031 Basel, Switzerland
[3] Harvard Univ, Brigham & Womens Hosp, Sch Med, Ctr Arrhythmia Prevent,Dept Med, Boston, MA 02115 USA
[4] Harvard Univ, Brigham & Womens Hosp, Sch Med, Div Prevent Med,Dept Med, Boston, MA 02115 USA
[5] Harvard Univ, Brigham & Womens Hosp, Sch Med, Div Cardiovasc,Dept Med, Boston, MA 02115 USA