Abstract 13267: Angina Burden and Coronary Vascular Function in Women With Ischemia and No Obstructive Coronary Arteries—Role of Oxygenation-Sensitive Cardiovascular Magnetic Resonance Imaging

Introduction: Patients with ischemia and no obstructive coronary arteries (INOCA) often have coronary microvascular dysfunction (CMD). An association between higher angina burden (lower Seattle Angina Questionnaire [SAQ] scores) and increased severity of CMD has previously been reported. Oxygenation-Sensitive Cardiovascular Magnetic Resonance (OS-CMR) is a novel approach that can potentially evaluate CMD. To date, the relationship between angina burden and OS-CMR biomarkers has not been elucidated. Methods: We investigated the association between angina burden, quantified by the mean and 5 individual components of the SAQ, with measures of myocardial oxygenation, using OS-CMR. More severe CMD is reflected by a decreased % signal intensity (SI) change after hyperventilation (Breathing-enhanced Myocardial REserve, B-MORE), calculated by [(Hyperventilation - Breath Hold)/Breath Hold] x 100%. Univariable linear regression analysis was used to investigate the associations. Results: In 44 women with INOCA (mean age 55.1±0.9 years), B-MORE was 5.0±1.4% (Table). Several components of the SAQ were associated with OS-CMR measures of CMD [physical limitation (R 2 =0.281, Beta=0.530, p=0.042), angina frequency (R 2 =0.216, Beta=0.465, p=0.039), disease perception (R 2 =0.254, Beta=0.504, p=0.024), and the mean overall SAQ (R 2 =0.285, Beta=0.534, p=0.015)] (Panel Figure). Conclusion: In women with INOCA, angina burden is associated with coronary vascular function, as assessed by OS-CMR. Therefore, this novel approach may provide objective information to detect the presence of CMD.