This is a clinical study to evaluate the effectiveness and explore the possible working mechanisms of a traditional Chinese herbal formula called Yixin Powder. The study focuses on patients with stable angina pectoris (chest pain) caused by coronary heart disease (CHD), who are diagnosed with a specific Chinese medicine pattern known as "qi deficiency and blood stasis," based on the "weak pulse at yang and wiry pulse at yin" theory.
The study hypothesizes that adding Yixin Powder to standard Western medication will be beneficial for these patients. To test this, participants diagnosed with this condition will be randomly assigned to one of two groups. One group will receive standard medication alone, while the other group will receive the same standard medication plus Yixin Powder. The effects of the treatments will be compared between the two groups.