A study to determine the most appropriate dose of MK7418 in heart failure patients presenting with symptoms of volume overload requiring increased diuretic doses.

Inclusion Criteria:

• Be able to provide written informed consent,
• Be a male or female at least 18 years of age,
• Be hospitalized for fluid overload requiring IV diuretic therapy
• History of use of diuretic therapy for CHF (including this admission),
• Be admitted to the hospital within 36 hours of the mandatory dose of IV furosemide 40 mg at between 2000 and 2200 hour on Day -1

Exclusion Criteria:

• Have had a myocardial infarction within 30 days prior to Day -1
• Be pregnant or breast-feeding
• Have received intravascular contrast material within the preceding 14 days; or have acute contrast nephropathy
• Have had implantation of an automated implanted cardiac defibrillator (AICD) or synchronization device within the preceding 7 days
• Currently require mechanical ventilation, ultrafiltration, or hemodialysis,
• Have symptomatic ventricular tachycardia
• Be admitted for heart transplant surgery or have had a heart transplant,
• Have any other concomitant life-threatening disease,
• Have participated in a clinical trial of an investigational drug or device within 30 days before randomization
• Have a positive urine pregnancy test (for women of child-bearing capacity)
• Have an allergy to soybean oil and/or eggs