RT Journal Article SR Electronic T1 Rationale and design of the Coronary Microvascular Angina Cardiac Magnetic Resonance Imaging (CorCMR) diagnostic study: the CorMicA CMR sub-study JF Open Heart JO Open Heart FD British Cardiovascular Society SP e000924 DO 10.1136/openhrt-2018-000924 VO 5 IS 2 A1 David Corcoran A1 Thomas J Ford A1 Li-Yueh Hsu A1 Amedeo Chiribiri A1 Vanessa Orchard A1 Kenneth Mangion A1 Margaret McEntegart A1 Paul Rocchiccioli A1 Stuart Watkins A1 Richard Good A1 Katriona Brooksbank A1 Sandosh Padmanabhan A1 Naveed Sattar A1 Alex McConnachie A1 Keith G Oldroyd A1 Rhian M Touyz A1 Andrew Arai A1 Colin Berry YR 2018 UL http://openheart.bmj.com/content/5/2/e000924.abstract AB Introduction Angina with no obstructive coronary artery disease (ANOCA) is a common syndrome with unmet clinical needs. Microvascular and vasospastic angina are relevant but may not be diagnosed without measuring coronary vascular function. The relationship between cardiovascular magnetic resonance (CMR)-derived myocardial blood flow (MBF) and reference invasive coronary function tests is uncertain. We hypothesise that multiparametric CMR assessment will be clinically useful in the ANOCA diagnostic pathway.Methods/analysis The Stratified Medical Therapy Using Invasive Coronary Function Testing In Angina (CorMicA) trial is a prospective, blinded, randomised, sham-controlled study comparing two management approaches in patients with ANOCA. We aim to recruit consecutive patients with stable angina undergoing elective invasive coronary angiography. Eligible patients with ANOCA (n=150) will be randomised to invasive coronary artery function-guided diagnosis and treatment (intervention group) or not (control group). Based on these test results, patients will be stratified into disease endotypes: microvascular angina, vasospastic angina, mixed microvascular/vasospastic angina, obstructive epicardial coronary artery disease and non-cardiac chest pain. After randomisation in CorMicA, subjects will be invited to participate in the Coronary Microvascular Angina Cardiac Magnetic Resonance Imaging (CorCMR) substudy. Patients will undergo multiparametric CMR and have assessments of MBF (using a novel pixel-wise fully quantitative method), left ventricular function and mass, and tissue characterisation (T1 mapping and late gadolinium enhancement imaging). Abnormalities of myocardial perfusion and associations between MBF and invasive coronary artery function tests will be assessed. The CorCMR substudy represents the largest cohort of ANOCA patients with paired multiparametric CMR and comprehensive invasive coronary vascular function tests.Ethics/dissemination The CorMicA trial and CorCMR substudy have UK REC approval (ref.16/WS/0192).Trial registration number NCT03193294.