1. West of Scotland Regional Heart & Lung Centre, Golden Jubilee National Hospital, Agamemnon Street, Clydebank, G81 4DY, UK
2. Institute of Cardiovascular & Medical Sciences, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK
3. University of Geneva, 24 rue de Général-Dufour, 1211 Genève 4, Switzerland