[1] Univ Oslo, Rikshosp, Oslo Univ Hosp, Dept Psychosomat Med, N-0027 Oslo, Norway
[2] Univ Oslo, Rikshosp, Oslo Univ Hosp, Dept Cardiol, N-0027 Oslo, Norway
[3] Univ Oslo, Rikshosp, Oslo Univ Hosp, Dept Res & Educ, N-0027 Oslo, Norway
[4] Univ Oslo, Rikshosp, Oslo Univ Hosp, Dept Thorac Surg, N-0027 Oslo, Norway