1. Cardiology Department, Royal Infirmary of Edinburgh, 51 Little France Cres, Edinburgh, Scotland, EH16 4SA, UK
2. Cardiology Department, Freeman Hospital, Freeman Rd, Newcastle upon Tyne, NE7 7DN, UK
3. Department of Stroke Medicine, Cumberland Infirmary, Newtown Rd, Carlisle, CA2 7HY, UK
4. Cardiology Department, Cumberland Infirmary, Newtown Rd, Carlisle, CA2 7HY, UK