Abstract 13544: Myocardial Perfusion Reserve by Cardiac Magnetic Resonance Imaging is Related to Angina Stability in Women with Signs and Symptoms of Ischemia and No Obstructive Coronary Artery Disease: Results from the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation Coronary Vascular Dysfunction (WISE-CVD) Study

Abstract

Background: Cardiac magnetic resonance imaging (CMRI) is an emerging technique for evaluation of subjects with signs and symptoms of ischemia without obstructive coronary artery disease (CAD). CMRI-derived Myocardial Perfusion Reserve Index (MPRI) is a semi-quantitative assessment of perfusion (lower values indicate worse perfusion) reserve. Accordingly, we evaluated if MPRI is related to angina characteristics among these subjects.

Methods: Subjects from the Women’s Ischemia Syndrome Evaluation Coronary Vascular Dysfunction (WISE CVD) multi-center National Heart, Lung, and Blood study presenting with signs and symptoms of ischemia but no obstructive CAD (<50% stenosis) on angiography from 2009-12 were studied. CMRI at 1.5 Tesla used a standardized protocol of adenosine stress and rest perfusion. MPRI was calculated for 16 segments (AHA model) using CASS software (Pie Medical®). The Seattle Angina Questionnaire (SAQ), measuring 5 functional dimensions, was used to characterize symptoms (higher scores indicate better health) at study entry. MPRI values and SAQ responses were compared using linear regression analysis.

Results: The overall group (n=198) age was 54.6±10.6 (mean±SD) years, body mass index 30.2±8.5 kg/m2 and 16 segment MPRI 1.79±0.49(range: 0.80 - 3.26). All subjects reported symptoms as SAQ scale responses ranged from 0 to 100. Mean MPRI was related to angina stability but not physical limitations, angina frequency, treatment satisfaction or disease perception (table). This relationship was seen for sub-endocardial and sub-epicardial sub-segmental MPRI, whole heart and mid ventricular segments.

Conclusion: Myocardial perfusion reserve measured by CMRI is related to angina stability among women with signs and symptoms of ischemia but no obstructive CAD. These results suggest that the quality of these patients’ symptoms is important and meaningful since it is validated by an association with the objective perfusion parameter.