The purpose of this study is to investigate whether an angiotensin II receptor blocker (olmesartan), in addition to conventional treatment, will reduce the mortality and morbidity in hypertensive patients with stable chronic heart failure.

Inclusion Criteria:

Patients who meet all of the following criteria.

• Patients with NYHA class II through IV chronic heart failure.
• Patients who have a history of hypertension or those who have antihypertensive medications.
• Patients who are aged 20 years or older and less than 80 years at the entry.
• Stable patients who have angiotensin converting enzyme inhibitor and/or beta-blocker.
• Patients who do not have angiotensin II receptor blocker.

Exclusion Criteria:

• Patients who have renal dysfunction (serum creatinine >=3.0mg/dL) or those who are receiving chronic hemodialysis.
• History of drug hypersensitivity to olmesartan.
• Patients who have severe liver dysfunction.
• History of angioedema.
• History of malignant tumor or life-threatening illness of poor prognosis.
• Pregnant or possibly pregnant patients.
• Cardiovascular surgery within 6months prior to the date of the entry.
• Acute myocardial infarction within 6 months prior to the date of the entry.
• Percutaneous coronary intervention or stent implantation within 6 months prior to the date of the entry.
• Other patients deemed unsuitable as subjects of the study by the treating physician.