A Study to Develop Additional Safety and Clinical Experience With NATRECOR hBNP (Nesiritide) in the Treatment of Patients With Worsening Congestive Heart Failure Who Require Inpatient Intravenous Therapy With Medications That Influence the Tone and Caliber of Blood Vessels

The purpose of this safety study is to evaluate NATRECORÂ® hBNP (a recombinant form of the natural human peptide normally secreted by the heart in response to heart failure), in subjects with worsening congestive heart failure for whom inpatient intravenous therapy with medications that influence the tone and caliber of blood vessels is deemed appropriate.

The data from these previous studies suggest that doses of NATRECOR® hBNP may be a potent agent for the treatment of acute congestive heart failure (CHF) with a unique combination of desirable effects on the flow of blood throughout the body; the hormones secreted by the nervous system; and support of copious salt outputs by the renal system not provided by currently available therapies. The purpose of this safety study is to evaluate NATRECOR® hBNP in subjects with symptomatic, decompensated congestive heart failure for whom inpatient intravenous therapy with medications that influence the tone and caliber of blood vessels (other than, or in addition to, IV diuretics) is deemed appropriate. This is a multi-center, randomized, open-label, safety study designed to compare two doses of NATRECOR® hBNP for the treatment of decompensated congestive heart failure. One treatment group receives NATRECOR® hBNP fixed-dose infusion IV bolus of 0.3 µg/kg followed by a 0.015 µg/kg/min infusion; group two receives IV bolus of 0.6 µg/kg followed by a 0.03 µg/kg/min infusion. The duration of NATRECOR® hBNP therapy is determined by the attending physician. The study hypothesis is that doses of NATRECOR® hBNP in the range of 0.015 to 0.03 µg/kg/min provide an optimal safety/efficacy profile for the treatment of decompensated CHF. One treatment group receives NATRECOR® hBNP fixed-dose infusion IV bolus of 0.3 µg/kg followed by a 0.015 µg/kg/min infusion; group two receives IV bolus of 0.6 µg/kg followed by a 0.03 µg/kg/min infusion. The duration of NATRECOR® hBNP therapy is determined by the attending physician.

Eligibility Criteria:
Inclusion Criteria:

* Patients with a previous history of chronic congestive heart failure (CHF)
* presenting with symptomatic, decompensated CHF for inpatient intravenous therapy with medications that influence the tone and caliber of blood vessels (other than, or in addition to, diuretics)

Exclusion Criteria:

* Patients with myocardial ischemia within the past 48 hours
* having significant valvular stenosis, obstructive cardiomyopathy, constrictive pericarditis or primary pulmonary hypertension
* being treated with intravenous (IV) therapy with medications that influence the tone and caliber of blood vessels for \> 4 hours for this episode of CHF
* already being treated with IV therapy with medications that influence the tone and caliber of blood vessels that cannot be discontinued
* having cardiogenic shock, systolic blood pressure consistently \< 90 mm Hg or other significant blood circulation instability.