Myocardial Scar Is Prevalent and Associated With Subclinical Myocardial Dysfunction in Women With Suspected Ischemia But No Obstructive Coronary Artery Disease

chronic ischemic heart disease ◼ magnetic resonance imaging ◼ women W omen with suspected ischemia and no obstructive coronary artery disease (INOCA) have a high prevalence of coronary microvascular dysfunction 1 and an elevated rate of major adverse cardiac events, including nonfatal myocardial infarction (MI). 2 Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) imaging accurately visualizes and characterizes myocardial scar, which predicts major adverse cardiac events.3 The prevalence, incidence, and scar pattern in women with INOCA is not well characterized.We evaluated LGE in women with suspected INOCA in the WISE-CVD study (Women's Ischemia Syndrome Evaluation-Coronary Vascular Dysfunction; URL: http://www.clinicaltrials.gov.Unique identifier: NCT00832702).Participants in the WISE-CVD study included women with suspected INOCA as previously described.4 The study was approved by the site institutional review committees.All participants gave informed consent.Of the 369 total women enrolled, 341 underwent baseline CMR with LGE; 1 was excluded because of inadequate quality.A subset of 145 underwent invasive coronary reactivity testing.5 The SAQ (Seattle Angina Questionnaire) was completed at baseline and 1-year follow-up.Retrospective review included clinical diagnosis of MI, electrocardiogram, and troponin levels.A subset of 200 participants underwent repeat CMR with LGE at 1-year follow-up; 179 were included with baseline CMR and follow-up within 1 year of study completion.All scans were performed on a 1.5T scanner (Magnetom Avanto, Siemens Healthcare) and analyzed by the WISE-CMR core lab. 4 A total 0.2 mmol/kg gadolinium-based contrast (Optimark, gadoversetamide) in divided doses was used, and LGE images were acquired using a 2D inversion-recovery turbo FLASH (slice thickness 8 mm, skip 2 mm, TE 3 ms, TR 0.7 s, flip angle 25 degrees).Scans were read blinded to clinical information; the extent of LGE was quantified using the full width at half-maximum method.LGE type was defined as typical scar pattern when subendocardial or transmural and localized to a coronary artery distribution and atypical scar pattern when midmyocardial or epicardial.LGE quantification was performed by a single experienced operator using postprocessing software (QMass, Medis) by delineating regions of LGE across all the multislice short axis acquisitions.Fisher exact or 2-sample t tests were used to compare groups.Linear regression with log transformation of the troponin variable was used to assess the relationship between troponin level and scar size.LGE was present at baseline in 26 (8%) women who were younger, had lower blood pressure, were more likely to be prescribed calcium channel blockers and clopidogrel, and had lower SAQ treatment satisfaction, compared with women without LGE (Table).Women with LGE also had lower left ventricular ejection fractions and higher end-diastolic and end-systolic volumes but no difference in myocardial perfusion reserve index.There were also no differences in the invasive variables in the coronary reactivity testing subset.