SHengXIaN-QuYu DEcoction in Heart Failure With Reduced and Mildly Reduced Ejection Fraction

Inclusion Criteria: 1. Male or female, aged ≥18 years at the time of consent. 2. Established documented diagnosis of symptomatic HFrEF (NYHA functional class II-IV). 3. LVEF \<50%. 4. NT-proBNP \>600 pg/ml or BNP ≥150 pg/ml (or if hospitalized for heart failure within the previous 12 months, NT-proBNP ≥400 pg/ml or BNP ≥100 pg/ml) at enrolment. 5. Provision of signed informed consent prior to any study specific procedures. Exclusion Criteria: 1. Current acute decompensated HF or hospitalization due to decompensated HF, ACS, stroke or transient ischemic attack (TIA), coronary revascularization (percutaneous coronary intervention \[PCI\] or coronary artery bypass grafting \[CABG\]) or valvular repair/replacement, or other major cardiovascular surgery within 4 weeks prior to enrolment. 2. Uncontrolled severe arrhythmia. 3. Planned to undergo heart transplantation or device implantation. 4. Hepatic impairment aspartate transaminase \[AST\] or alanine transaminase \[ALT\] \>3x the upper limit of normal \[ULN\]; or total bilirubin \>2x ULN at time of enrolment). 5. Severe infection. 6. eGFR \<30 mL/min/1.73 m\^2 by CKD-EPI. 7. Active malignancy requiring treatment at the time of visit 1. 8. Women of child-bearing potential who are not willing to use a medically accepted method of contraception that is considered reliable in the judgment of the investigator OR women who have a positive pregnancy test at enrolment or randomization OR women who are breast-feeding. 9. Any condition outside the CV and renal disease area, such as but not limited to malignancy, with a life expectancy of less than 1 years based on investigator's clinical judgement. 10. Systolic blood pressure \< 90 mmHg, or systolic blood pressure ≥ 180 mmHg, or diastolic blood pressure ≥ 110 mmHg on 2 consecutive measurements. 11. Heart failure due to infiltrative cardiomyopathies(cardiac amyloidosis, etc.), fulminant myocarditis, constrictive pericarditis. 12. Participation in another clinical study. 13. Inability of the patient, in the opinion of the investigator, to understand and/or comply with study medications, procedures and/or follow-up OR any conditions that, in the opinion of the investigator, may render the patient unable to complete the study.