The purpose of this study is to investigate the non-inferiority of bisoprolol to carvedilol by evaluating tolerability (The probability that administered maintenance dose reaches the maximum will be determined as an indicator) as a primary endpoint when bisoprolol or carvedilol is administered for 48 weeks to Japanese chronic heart failure patients. In addition, the safety and efficacy of bisoprolol will be investigated.

Inclusion Criteria:

As a result of diagnosis and tests before registration, a patient who is considered by an investigator to meet all requirements and to have ability to consent can be enrolled.

1. Primary disease: In principle, ischemic heart disease or dilated cardiomyopathy.
2. Heart failure patients with 40% or less of left ventricular ejection fraction (LVEF) .
3. Patients in NYHA functional classification Class II, III, or IV (including a medical history).
4. Basic treatment: In principle, patients undergoing treatment with an ACE inhibitor (or angiotensin receptor blocker (ARB)), a diuretic, a digitalis preparation, etc.
5. Patients who had not undergone treatment with a beta-blocker (except eye drops) within 8 weeks before the registration date.
6. Age: Patients aged 20 to less than 85 on the day of obtaining written informed consent.
7. Hospitalized/outpatient: Either hospitalized or outpatient status.
8. Gender: Male or Female

Exclusion Criteria:

Patients who meet any of the following exclusion criteria at the time of registration will be excluded:

1. Patients who are considered not to be candidates for administration of bisoprolol or carvedilol.
2. Patients who have developed acute myocardial infarction within 8 weeks before the registration day.
3. Patients who have history of stroke or serious cerebrovascular accident within 1 year before the registration day.
4. Patients with poor prognosis and life-threatening disease, such as malignant tumor, or such medical history within 5 years before the registration day.
5. Patients who are scheduled to undergo coronary revascularization (Coronary artery bypass grafting; CABG, Percutaneous coronary intervention; PCI) during the study period.
6. Patients who are pregnant, lactating, may become pregnant, or want to become pregnant during the study.
7. Patients from whom written informed consent cannot be obtained.
8. Patients who are judged by an investigator to be inappropriate for this study for any other reason.