The aim of present study is to evaluate the efficacy and safety of Extended-Release Carvedilol Sulfate versus Sustained-release Metoprolol Succinate in Patients With Mild or Moderate Chronic Heart Failure.

Inclusion Criteria:

• Males or Females
• Aged from 18 to 75 years
• New York Heart Association(NYHA) classification Ⅱ-Ⅲ
• At screening, subject has an LVEF<0.45
• Have received optimal therapy with an Angiotensin converting enzyme inhibitors or angiotensin receptor blocker for 4 weeks before enrollment
• Subjects with symptoms of Stable heart failure do not need intravenous injection diuretics,cardiac inotropes or vasodilators
• Willing to provide written informed consent

Exclusion Criteria:

• Current treatment on any Class I or III antiarrhythmic, except amiodarone or beta-blockers
• Current treatment on calcium antagonists except for long-acting dihydropyridine agents
• Have a history of acute coronary syndrome,cerebral apoplexy or transient ischemic attack with 3 months
• Have a history of cardio-vascular surgery or other vessel operations with 3 months
• Have a history of sustained ventricular tachycardia or ventricular fibrillation with 3 months
• Have a plan to receive coronary revascularization or heart transplantation
• Uncontrolled ventricular arrhythmias (not controlled with antiarrhythmic therapy or an implantable defibrillator)
• Subjects with uncorrected primary obstructive or severe regurgitative valvular disease，nondilated (restrictive) or hypertrophic cardiomyopathy
• Sitting systolic blood pressure≤90mmHg (based on an average of 3 readings)
• Current decompensated heart failure
• Second or third degree heart block，or sick sinus syndrome，a pacemaker is not placed
• Contraindication to vasodilators
• Have a history of cardiac resynchronization therapy or
• Have received cardioverter defibrillator or pacemaker with 1 month
• Resting heart rate<50 beats per minute(based on the average of 3 readings)
• Elevated liver enzymes (alanine aminotransferase or aspartate aminotransferase levels greater than 3 times upper limit of normal)
• Serum creatinine levels greater than 2 times upper limit of normal
• Current clinical evidence of obstructive pulmonary disease (e.g., asthma or bronchitis) requiring inhaled or oral bronchodilator or steroid therapy
• History of drug sensitivity or allergic reaction to alpha or beta-blockers
• Contraindication or intolerance to beta-blockers
• Pregnant or lactating women and women planning to become pregnant
• Has any systemic disease, including cancer, with reduced life expectancy (<12 months)
• Use of an investigational drug within 30 days of enrollment
• Participation in an investigational device trial within 30 days of enrollment
• Known drug or alcohol abuse 1 year prior to enrollment
• Has a history of psychological illness/condition that interferes with ability to understand or complete requirements of the study
• In the opinion of the investigator the subject is known to be noncompliant with prescribed medication regimen