1 Department of Cardiology, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen BT74 6DN, UK. Electronic address: e.p.mccarron@doctors.org.uk.
2 Department of Cardiology, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen BT74 6DN, UK.
3 Department of Acute Medicine, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen BT74 6DN, UK.