[1] Univ Hosp Bern, Dept Cardiol, CH-3010 Bern, Switzerland
[2] Univ Bern, Inst Social & Prevent Med, Bern, Switzerland
[3] Triemli Municipal Hosp, Dept Cardiol, Zurich, Switzerland
[4] Univ Zurich Hosp, Dept Cardiol, CH-8091 Zurich, Switzerland
[5] Univ Hosp Bern, Clin Trials Unit, CH-3010 Bern, Switzerland