Department of Cardiology, Royal United Hospital, Combe Park, Bath, BA1 3NG, UK; Department for Health, University of Bath, Claverton Down, Bath, BA2 7AY, UK. Department of Cardiology, Royal United Hospital, Combe Park, Bath, BA1 3NG, UK. Department for Health, University of Bath, Claverton Down, Bath, BA2 7AY, UK. Department of Laboratory Medicine, Salisbury District Hospital, Odstock Road, Salisbury, SP2 8BJ, UK. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK. Department for Health, University of Bath, Claverton Down, Bath, BA2 7AY, UK; Department of Radiology, Royal United Hospital, Combe Park, Bath, BA1 3NG, UK. Electronic address: j.rodrigues1@nhs.net.