The study is a randomized, placebo controlled, multi-center, single dose study to evaluate cardiac hemodynamics and safety of iv SLV320 in 110 subjects with congestive heart failure requiring diuretic treatment. Each subject will receive one dose of SLV320 or placebo or furosemide. The study consists of three visits (or study days when in-subjects are included). Ambulatory subjects will be in hospital for two nights and one day.

Inclusion Criteria:

• history of chronic, symptomatic, mild to severe (NYHA Class II-IV) CHF for at least three months requiring treatment with diuretics and with documented systolic dysfunction
• on stable doses of their individually optimized medication regimen for at least one week prior to enrollment

Exclusion Criteria:

• required hospitalization (for cardiovascular disease) or adjustment of background medications for CHF
• orthostatic hypotension or symptomatic orthostasis
• sitting systolic or diastolic blood pressure < 90 mmHg
• 2nd or 3rd degree atrio-ventricular block or sick sinus syndrome
• heart rate of < 50 or > 110 bpm on the ECG
• transplanted heart
• heart failure due to primary valvular disease (unless surgically corrected), obstructive cardiomyopathy, pericardial disease, cor pulmonale or congenital heart disease
• hemodynamically significant left ventricular outflow tract obstruction