[1] Osped Riuniti, Dept Cardiol, I-16033 Lavagna, Italy
[2] Osped Riuniti, Arrhythmol Ctr, I-16033 Lavagna, Italy
[3] Osped Civile, Div Cardiol, Cento, Italy
[4] Univ Minnesota, Div Cardiovasc, Cardiac Arrhythmia Serv, Minneapolis, MN 55455 USA
[5] Karolinska Hosp, Thorac Clin, Dept Cardiol, Electrophysiol & Arrhythmia Serv, S-10401 Stockholm, Sweden
[6] CHU Brest, Hop Cavale Blanche, Dept Cardiol, F-29285 Brest, France
[7] Univ Copenhagen, Gentofte Hosp, Dept Cardiol, Hellerup, Denmark
[8] Leiden Univ, Med Ctr, Dept Neurol & Clin Neurophysiol, Leiden, Netherlands
[9] Manchester Royal Infirm, Manchester Heart Ctr, Manchester, Lancs, England
[10] Goethe Univ Frankfurt, Kardiol Klinicum, Med Klin 4, D-6000 Frankfurt, Germany
[11] Univ Hosp Motol, Kardioctr, Prague, Czech Republic
[12] Univ Pittsburgh, Dept Med, Pittsburgh, PA 15260 USA
[13] Newcastle Univ, Royal Victoria Infirm, Inst Hlth Elderly, Newcastle Upon Tyne NE1 4LP, Tyne & Wear, England
[14] Grochowski Hosp, Med Ctr Postgrad Educ, Dept Cardiol, Warsaw, Poland
[15] Hosp Gen Valle Hebron, Dept Cardiol, Barcelona, Spain
[16] Osped Umberto 1, Div Cardiol, Venice, Italy
[17] Royal Brompton Hosp, Dept Cardiol, London SW3 6LY, England
[18] Onassis Cardiac Surg Ctr, Dept Cardiol 2, Athens, Greece
[19] Univ Amsterdam, Acad Med Ctr, Dept Internal Med, NL-1105 AZ Amsterdam, Netherlands