Efficacy and Safety Study of Tolvaptan to Treat Patients With Cardiac Edema

Inclusion Criteria: * Patients treated with one of the oral diuretic therapy standards （include the patients who will be treated with one of the oral diuretic therapy standards from the beginning of the observation period）: 1. Only 40 mg/day furosemide taken orally or other oral loop diuretics equivalent to 40 mg/day furosemide note 1) 2. Combination treatment of oral loop diuretics and thiazide diuretics (no dosage limitation) 3. Combination treatment of oral loop diuretics and aldosterone antagonists (no dosage limitation) * Because of the existence of excess body fluid retention, the congestive heart failure patient has at least one of these symptoms (the lower extremity edema, pulmonary congestion note 2), or jugular vein engorgement). * 20-85 years of age (inclusive) at the time of signing the informed consent document. * Gender: male or female. * Inpatients or patient who would be hospitalized from one day before the observation period to the end of efficacy evaluation examination after the last dosing (from Day -4 to the end of efficacy evaluation examination after the last dosing). * Patient who have signed the informed consent form. Exclusion Criteria: * Patients equipped with circulatory assistant device. * Patients with any of following diseases, complications or symptoms: 1. Suspected decreased blood volume 2. Obstructive hypertrophic cardiomyopathy 3. Severe aortic stenosis 4. Hepatic coma * Patients with history of acute myocardial infarction within 30 days prior to screening. * Patients with diagnosed active myocarditis or amyloid cardiomyopathy. * Patients with the following diseases, complications or symptoms: 1. Poorly controlled diabetes with a fasting glucose more than 220 mg/dL (or 12.21 mmol/L) 2. Anuria 3. Dysuria caused by urethral stricture, calculus or tumor * Patients with the following medical history of: 1. Sustained ventricular tachycardia or ventricular fibrillation within 30 days prior to screening 2. History of cerebrovascular accident within the past 30 days 3. Past allergy or hypersensitive reactions to benzodiazepines (e.g. mozavaptan hydrochloride or benazepril hydrochloride) * Obese patients whose body mass index (BMI = body weight (kg) / height (m)2 ) is more than 35. * Patients with systolic pressure below 90 mmHg in supine position. * Patients with any of the following abnormal laboratory test parameters: 1. Total bilirubin \> 2.5 times the upper limits of normal value 2. Serum creatine \> 2.5 times the upper limits of normal value 3. Serum Na+ \> 145 mmol/L (or higher than the upper limits of normal value) 4. Serum K+ \> 5.5 mmol/L * Patients who unable to take medicine orally. * Female patients who are pregnant, breast-feeding, at childbearing ages, or with pregnancy plan. * Patients who participated in clinical trials of other medicine and took other study drugs within 30 days prior to sign the informed consent form. * Patients who participated in the clinical trial of Tolvaptan and took Tolvaptan previously. * Patients who have received approved Tolvaptan tablets (Trade name: Samsca) previously. * Except for the above, patients who were unsuitable to participate in this trial in the investigator's opinion.