Inclusion Criteria:

Patients must meet all of the following inclusion criteria to be eligible for participation in the study

• Age _ 18 years.
• At least two hospital admissions or equivalent treatment (e.g., Emergency Department/observation unit admissions or unscheduled clinic visits) with IV vasoactive agents (such as IV inotropes, Natrecor®, or nitroglycerin for acutely decompensated CHF) within the last 12 months, with at least one of these admissions in the past 30 days. (Note: Infusions of diuretics in an outpatient setting should not be counted as a treatment to satisfy this inclusion criteria. The major reason for a hospital admission should be for the treatment of acutely decompensated CHF).
• Able to be enrolled and initiate treatment with study drug within 5–30 days of last hospital discharge or equivalent treatment of acutely decompensated CHF.
• Baseline NYHA Functional Classification III/IV for at least 2 months prior to randomization (see Appendix 4).
• Receiving optimal treatment with long term oral medications (e.g., diuretics, ACE inhibitors, and beta blockers, unless beta blockers or ACE inhibitors are documented to be contraindicated or not tolerated).
• Ambulatory and able to participate in the 6-minute walk test.
• Result of 6-minute walk test is < 400 meters.
• Have available transportation and are able to attend clinic visits at least once weekly for 12 weeks.
• Agree to come in to the clinic at least one time each week for 13 weeks and to be available for follow up for three additional weeks.
• Agree to receive infusions of Natrecor®, or possibly other medications, at least as frequently as once per week for 12 weeks.
• Females of childbearing potential must be willing to use two forms of contraception.
• Understood, and signed a written Informed Consent Form before initiation of protocol specified procedures.

Exclusion Criteria:

Patients meeting any of the following exclusion criteria are not eligible for participation in the study

• Systolic blood pressure consistently less than 90 mm Hg.
• Have had or during the course of the study are anticipated to have any organ transplantation (heart, liver, lung, and kidney).
• Unable or unwilling to discontinue intermittent or continuous infusions of inotropes if randomized to a Natrecor® treatment group.
• Have had a bi-ventricular pacemaker placed within past 60 days or an automatic implantable cardiac defibrillator (AICD) placed within the past 30 days.
• Have left ventricular assist device in place (LVAD).
• Cardiogenic shock, volume depletion, or any other clinical condition that would contraindicate the administration of Natrecor®.
• Currently receiving chronic dialysis or the expectation that dialysis will be required during the course of the study.
• Possible allergic reaction or sensitivity to Natrecor®.
• Females of child bearing potential with a positive pregnancy test, pregnant or nursing mothers, or suspected pregnancy.
• Medical condition so severe that survival for the treatment and follow-up periods is not likely.
• Medical condition immediately prior to randomization is such that hospitalization is needed or probably imminent.
• Concurrent therapy with another investigational drug or device without prior approval from Scios.
• Unwillingness or inability to comply with study requirements including informed consent, weekly clinic visits, and the follow-up period.
• Evidence of acute myocardial infarction within the past 30 days.