Abstract 4371441: Functional Capacity, Average Daily Step Count, and Angina among Women with Coronary Microvascular Dysfunction Compared to Obstructive Coronary Artery Disease and Healthy Control

Background: Approximately 50% of women with ischemia but no obstructive coronary artery disease have coronary microvascular dysfunction (CMD), a condition associated with adverse cardiovascular outcomes. Postmenopausal women with CMD experience recurrent chest pain, reduced functional capacity, fatigue, and impaired quality of life (QoL), but direct comparisons of women with obstructive coronary disease (oCAD) or healthy controls are lacking. We therefore examined angina-related physical limitations and QoL across these three groups. Methods: A total of 48 postmenopausal women were grouped as follows: CMD (n=14, CFR or MFR ≤2.5), oCAD (n=12, >50% stenosis), and Controls (n=22, normal stress tests, no cardiac history or medications). Demographics, cardiac risk factors, and subscale scores from the validated Seattle Angina Questionnaire (SAQ)—including physical limitation, angina stability, angina frequency, treatment satisfaction, and QoL—were assessed. The Duke Activity Status Index (DASI) was used to assess functional capacity and a score ≤34 is prognostic of major adverse cardiac events. Total step counts for 7 days were measured by Actiwatch wrist actigraphy. Descriptive statistical analysis and Spearman rank correlations were performed for data analysis. Results: Baseline characteristics and cardiovascular risk factors were comparable among all three groups. However, there was a higher percentage of hypertension among CMD and a higher percentage of hyperlipidemia in oCAD as opposed to the other groups. The treatment satisfaction SAQ subscale demonstrated a lower satisfaction score in the CMD group compared to the oCAD group (p=0.012). Despite similar angina burden compared to oCAD, DASI score was significantly lower in CMD (20.5±14.0) as opposed to oCAD (37.1±14.3) with p=0.013, even after BMI adjustment. A positive correlation was observed between DASI scores and step counts in the CMD group ( R = 0.84, p =0.0045), but not in oCAD. Conclusion: Postmenopausal women with CMD exhibit physical limitation and reduced functional capacity compared to other groups. These impairments are associated with lower treatment satisfaction, physical activity, and QoL. Tailored exercise and rehabilitation strategies targeting physical function may improve both functional capacity and QoL in this at-risk CMD population.