Sex difference of coronary microvascular dysfunction evaluated by coronary flow reserve will be assessed in patients with non-obstructive coronary artery disease
Typical/atypical chest pain or ischemic symptoms including dyspnea
No significant coronary artery stenosis (<50% stenosis) in coronary angiography or computed tomography
≥ Moderate valvular heart disease
Congenital heart disease
Chronic renal failure (estimated glomerular filtration rate <30 ml/min/1.73m2) or end-stage renal failure undergoing hemodialysis or peritoneal dialysis
Asthma, chronic obstructive pulmonary disease and primary pulmonary hypertension