 This study is part of the CALIBER Cardiovascular disease research using linked bespoke studies and electronic records programme funded over 5 years from the NIHR and Wellcome Trust. The central theme of the CALIBER research is linkage of the Myocardial Ischaemia National Audit Project MINAP with primary care CPRD and other resources. The overarching aim of CALIBER is to better understand the aetiology and prognosis of specific coronary phenotypes across a range of causal domains, particularly where electronic records provide a contribution beyond traditional studies. CALIBER has received both Ethics approval ref 09H081016 and ECC approval ref ECC 2-06b2009 CALIBER dataset. 