To investigate the efficacy and safety of Qishenyiqi in patients with microvascular angina pectoris. Long-term follow-up of 1 year will be performed to evaluate the effect of Qishenyiqi on coronary flow reserve and adverse cardiovascular events in patients with coronary microvascular disease.

Inclusion Criteria:

• Repeated chest pain attacks with typical exertional angina pectoris or resting angina pectoris attacks;
• Coronary normal or stenosis < 20%;
• Ischemic depression in ST segment during resting or exercise;
• Blood flow reserve (CFR) of the anterior descending coronary artery < 2.0;
• Subjects or their guardians agreed to participate in this study.

Exclusion Criteria:

• Previous myocardial infarction or PCI or CABG treatment;
• A history of heart failure;
• Severe arrhythmia;
• Refractory hypertension or hypertension accompanied by left ventricular wall thickness > 12 mm;
• Familial hypercholesterolemia;
• Takayasu arteritis, Kawasaki disease or coronary artery malformation;
• Pregnant or nursing, or having the intention to give birth within one year;
• Hepatic or renal dysfunction;
• Allergic to contrast agents or traditional Chinese medicines;
• Patients who participated in clinical research of other drugs within 3 months before being selected.