Yiqi Fumai Lyophilized Injection for Chronic Heart Failure Caused by Coronary Heart Disease

Inclusion Criteria: 1. Age 40 to 80 years, inclusive, of any sex. 2. Confirmed coronary heart disease or chronic coronary syndrome according to the protocol-defined criteria, supported by at least one verifiable item such as prior myocardial infarction, prior PCI or CABG, at least 50% stenosis in a major epicardial coronary artery on angiography or coronary CT angiography, FFR of 0.80 or less, iFR of 0.89 or less, or imaging evidence of prior ischemic infarction or scar with corresponding coronary atherosclerosis. 3. Heart failure judged to be caused primarily by coronary heart disease, with objective evidence supporting an ischemic cause and no more likely major nonischemic cause. 4. A documented diagnosis of chronic heart failure for at least 3 months, or verifiable persistent heart-failure treatment with structural or functional cardiac abnormality; and stable chronic heart failure with reduced ejection fraction at Day 0, defined by LVEF of 40% or less, NT-proBNP of at least 450 pg/mL, and NYHA class II or III. 5. Clinical stability at Day 0: no initiation or intensification of intravenous inotropes, vasoactive drugs, mechanical ventilation, mechanical circulatory support, or ultrafiltration within the previous 72 hours; no increase in the daily dose of intravenous loop diuretic within the previous 24 hours; no acute pulmonary edema, worsening resting hypoxemia, or hypoperfusion; no clinically significant progressive deterioration in blood pressure or renal function; and core guideline-directed therapies generally stable for at least 2 weeks. A patient with acute decompensated heart failure during the current hospitalization may not later transition into this study. 6. Qi and Yin deficiency syndrome according to the protocol-defined traditional Chinese medicine criteria, requiring qualifying manifestations of both Qi deficiency and Yin deficiency, at least one secondary symptom, and compatible tongue and pulse findings. 7. The participant or legally authorized representative can understand the study, participates voluntarily, and signs the informed consent form before any study-specific procedure. 8. Able to complete efficacy, safety, quality-of-life, cost, and biospecimen assessments required by the protocol. 9. For women of childbearing potential, a negative urine or serum pregnancy test during screening; equivocal results or delayed menstruation require repeat testing. Exclusion Criteria: 1. Acute heart failure, acute decompensation of chronic heart failure, cardiogenic shock, malignant arrhythmia, acute respiratory failure, acute pulmonary edema, need for mechanical ventilation or mechanical circulatory support, or another critical condition requiring immediate rescue treatment. 2. Acute coronary syndrome or acute myocardial infarction within 1 month before enrollment if the investigator determines that it will materially affect efficacy, safety, or omics assessments. 3. PCI or CABG within 3 months before screening; CRT implantation or upgrade within 6 months before screening; or a definite plan for PCI, CABG, or CRT implantation or upgrade within the next 6 months. Prior CRT is not an absolute exclusion if it was performed at least 6 months earlier, device settings and clinical status are stable, and no major upgrade or parameter change is planned. 4. NYHA class IV, clinical instability, or inability to safely complete the short-term study procedures. 5. Heart failure caused primarily by severe valvular heart disease, primary cardiomyopathy, congenital heart disease, pericardial disease, cor pulmonale, severe pulmonary hypertension, thyroid dysfunction, severe anemia, infective endocarditis, or another noncoronary cause. 6. Severe hepatic, renal, or hematologic disease, including ALT or AST greater than 3 times the upper limit of normal, eGFR less than 30 mL/min/1.73 m2, dialysis, severe anemia, or another condition judged unsuitable by the investigator. 7. Markedly uncontrolled glucose metabolism: screening HbA1c of at least 9.0%; or confirmed fasting plasma glucose of at least 13.9 mmol/L after excluding acute infection, stress, and short-term glucocorticoid effects; or diabetic ketoacidosis, hyperosmolar hyperglycemic state, or another condition requiring urgent intensive glucose-lowering treatment. A single elevated random glucose value alone is not sufficient for exclusion. 8. Markedly uncontrolled blood pressure or hypotension risk: systolic blood pressure of at least 180 mmHg, diastolic blood pressure of at least 110 mmHg, systolic blood pressure below 90 mmHg, or persistently repeated diastolic blood pressure below 50 mmHg accompanied by dizziness, syncope, oliguria, cold extremities, hypoperfusion, or symptomatic hypotension. 9. Severe intracerebral hemorrhage, severe sequelae of cerebral infarction, severe cognitive impairment, psychiatric disorder, aphasia, or another condition that interferes with questionnaire assessment or follow-up data collection. 10. Active malignancy, severe infection, active autoimmune disease, or expected survival of less than 6 months. 11. Pregnancy or breastfeeding. 12. Known allergy to Yiqi Fumai lyophilized injection, red ginseng, Ophiopogon japonicus, Schisandra chinensis, or any excipient; or a prior serious adverse reaction to a similar product. 13. Participation in another clinical study that, in the investigator's judgment, may affect efficacy, safety, adherence, or economic evaluation in this study. 14. Current use, with planned continuation during the study, or inability to discontinue, of a Qi-tonifying and Yin-nourishing Chinese herbal decoction or proprietary Chinese medicine with effects overlapping those of the study drug. 15. Any other condition that the investigator considers unsuitable for participation.