[1] Department of Anesthesiology,
[2] University of Technology Aachen,undefined
[3] Pauwelsstrasse 30,undefined
[4] D-52 074 Aachen,undefined
[5] Germany e-mail: f.falter@altavista.net Tel. + 49(241)8 08 81 79 Fax + 49(2 41)8 88 84 06,undefined
[6] Department of Cardiology,undefined
[7] University of Technology Aachen,undefined
[8] Germany,undefined
[9] Pauwelsstrasse 30,undefined
[10] D-52 074 Aachen,undefined
[11] Germany,undefined