The purpose of this study is to assess a dose titration scheme, of a new drug (BAY58-2667) given intravenously, to evaluate if this is safe and can help to improve the well-being, symptoms (e.g. breathing) and outcome of decompensated heart failure. Patients living with chronic heart failure have a risk of increased number of hospitalisations because of worsening of their condition (decompensated heart failure). The current treatment of acute heart failure consists of oxygen and medical treatment with vasodilators and positive inotropic agents (drugs, which should strengthen the pump function of the heart) which have their limitations. Therefore there is a need for new drugs in treatment of acute heat failure.

Inclusion Criteria:

• Patients with decompensated chronic congestive heart failure, NYHA functional class III-IV, either ischemic or non-ischemic, requiring hospitalization, and with clinical indication for parenteral pharmacotherapy and invasive hemodynamic monitoring (i.e indwelling Swan-Ganz pulmonary artery catheter) and PCWP >/= 18 mmHg.
• Patients must have the clinical diagnosis of CHF made at least 3 month prior to enrollment.
• Male or female patients, age 18 years or more.

Exclusion Criteria:

• Females of child-bearing potential.
• Acute de-novo heart failure.
• Acute myocardial infarction and/or myocardial infarction within 30 days.
• Valvular heart disease requiring surgical intervention during the course of the study.