[1] Luzerner Kantonsspital, Div Cardiol, CH-6000 Luzern 16, Switzerland
[2] Univ Hosp Bern, Dept Gen Internal Med, Inselspital, Div Geriatr, CH-3010 Bern, Switzerland
[3] Univ Bern, Bern, Switzerland
[4] Luzerner Kantonsspital, Inst Radiol, CH-6000 Luzern 16, Switzerland
[5] Univ Basel Hosp, Dept Biomed, CH-4031 Basel, Switzerland