Nonobstructive CAD in Women: Sex-Specific CAD and Need for Ischemic Cardiac Disease Definition Changes
Among patients presenting with symptoms/signs suspect for IHD, the presence of obstructive CAD (e.g., identifying a flow-limiting lesion, FFR <0.80) is highly prevalent in men (and older women), and often associated with reduced LV systolic function. Diagnosis and risk stratification are prompt because guideline-specific diagnostic, preventive, and/or treatment strategies are available. By contrast, nonobstructive CAD (e.g., FFR ≥80) is highly prevalent among women (mostly younger and middle-aged women) with preserved LV systolic function. Additionally, pharmacological testing with acetylcholine and adenosine distinguishes those with macrovascular or microvascular spasm, endothelial dysfunction, and/or coronary microvascular dysfunction (CMD). These latter findings are associated with increased risk of adverse outcomes that include heart failure with preserved systolic function, acute coronary syndromes, and cardiovascular-related hospitalizations, as well as repeated testing. Unfortunately, no guideline-recommended assessment or management is available, except for symptom relief and CVD risk factor management. CAD = coronary artery disease; CVD = cardiovascular disease; FFR = fractional flow reserve; IHD = ischemic heart disease; LV = left ventricular.