[1] Univ East Anglia, Norwich Med Sch, Rosalind Franklin Rd, Norwich NR4 7UQ, England
[2] Norfolk & Norwich Univ Hosp, Dept Cardiol, Colney Lane, Norwich NR4 7TJ, England
[3] Univ Aberdeen, Aberdeen, Scotland
[4] Aberdeen Royal Infirm, Foresterhill Hlth Campus,Foresterhill Rd, Aberdeen AB25 2ZN, Scotland
[5] Royal Bournemouth Hosp, Castle Lane East, Bournemouth BH7 7DW, England
[6] Univ Western Australia, Fiona Stanley Hosp, Harry Perkins Inst Med Res, 5 Robin Warren Dr, Murdoch, WA 6150, Australia
[7] Cent & Northern Adelaide Hlth Serv, Eastwood, SA 5063, Australia
[8] Royal Brompton Hosp, Imperial Coll London, Dept Cardiol, Sydney St, London SW3 6NP, England