Renal Effects of Intrarenal Nesiritide

We will perform an open-label, parallel arm, controlled study of intrarenal nesiritide in 26 patients hospitalized with CHF. Patients will be admitted for CHF exacerbation and randomly but equally divided into treatment and placebo groups. Both arms will receive diuretics on admission as dictated by clinical need. They will then have an 8-hour diuretic-free period (overnight). Each arm will then have renal parameters (GFR, RPF, urine output, urinary sodium excretion) assessed using PAH and iothalamate. These parameters will be measured prior to administration of drug during period 1. Randomization will be performed via an interactive computerized call in program following completion of screening procedures and once patient has given informed consent. At time 0, treatment patients will be taken to the cardiac catheterization lab for placement of the Benephit Infusion System (Flow Medica). Placement involves femoral artery cannulation and introduction of a bifurcated infusion catheter into the arterial system to a destination at the level of renal arteries. This will be done under fluoroscopic guidance. When placement of catheter is completed, period 2 will begin with initiation of Study Drug infusion (IR nesiritide or IV D5W). Nesiritide will be diluted according to its labeled instructions in D5W to a final dilution of 6 mcg/mL. Placebo patients will receive IV D5W as a bolus and a continuous infusion of D5W at volumes equal to what they would have gotten had they been randomized to nesiritide. Intra-renal (IR) infusion of nesiritide will be given as a 2ug/kg bolus followed by an infusion of 0.01 mg/kg/min through the intrarenal catheter. The nesiritide infusion will continue for 6 hours. Period 3 begins at the 3-hour mark, at which time, both the placebo and treatment groups will be treated with boluses of intravenous furosemide. Both treatment arms will receive furosemide at this time. Blood drawn at 3 and 6 hours and urine collected between 3 and 6 hours will be used to determine GFR, RPF, Na excretion and urine output.