Study To Evaluate D-Ribose For The Treatment of Congestive Heart Failure

Inclusion Criteria: * written informed consent and Health Insurance Portability and Accountability Act authorization, as applicable; * symptomatic heart failure (NYHA Class II, III or IV) ≥ 30 days prior to current acute decompensation episode; * ≥2 of the following signs of acute decompensation: jugular venous distension, rales, dyspnea, and ≥ 1+ pedal edema; * admitted to the hospital ≤ 36 hours after initial evaluation; * discontinued from IV inotropic support ≥ 48 hours prior to Screening; * initiated Screening when subject has met the following criteria for stabilization: * exacerbating factors addressed; * near optimal volume status; * transition from IV to oral diuretic completed; * near optimal pharmacologic therapy achieved or intolerance documented; * completed Screening procedures and been randomized to treatment ≤ 7 days after hospital admission; * LVEF ≤ 35% ≤ 12 months prior to Screening. * if female, ≥ 2 years post-menopausal, surgically sterile, or practicing effective contraception; * if female, non-lactating, and if of child-bearing potential, has negative pregnancy test result at Screening; * willing to abstain from ribose-containing products during study. Exclusion Criteria: * significant medical condition(s) which, in Investigator's judgment, could compromise subject's welfare or confound study results; * significant hepatic, renal, or hematologic disorder/dysfunction beyond that expected from CHF alone; * Creatinine Clearance \<30.0 mL/min at Screening; * serum potassium level \<3.5 milliequivalent per liter or \>5.7 milliequivalent per liter, or a serum sodium level \<130 milliequivalent per liter at Screening; * systolic arterial blood pressure \<90 mm Hg at Screening; * received ultrafiltration during current admission; * cardiac surgery ≤ 60 days prior to Screening, except for percutaneous intervention; * planned revascularization procedures, electrophysiologic device or cardiac mechanical support implantation, cardiac transplantation, or other cardiac surgery ≤ 90 days after study enrollment; * functional mitral valve regurgitation \> moderate severity; * aortic regurgitation of at least moderate severity; * hemodynamically significant primary cardiac valvular disease; * myocardial infarction ≤ 30 days prior to Screening; * Acute Coronary Syndrome ≤ 30 days prior to Screening; * known or suspected right-to-left, bi-directional, or transient right-to-left cardiac shunt; * sustained ventricular tachycardia or ventricular fibrillation ≤ 30 days prior to Screening, unless automatic implantable cardioverter defibrillator is present; * atrial fibrillation within the past year; * CHF related to tachyarrhythmias or bradyarrhythmias; * CHF due to uncorrected thyroid disease, active myocarditis, or known amyloid cardiomyopathy; * angina at rest or with slight exertion and/or unstable angina; * diagnosed with hypertrophic cardiomyopathy; * cerebrovascular accident ≤ 6 months prior to Screening; * cardiogenic shock at any time from initial evaluation to randomization; * on cardiac mechanical support; * biventricular pacer placement ≤ 60 days prior to Screening or needed pacemaker placement during the current admission; * refractory, end-stage heart failure; * type I or type II diabetes; * history of pancreatitis; * current systemic infection; * urinary tract obstruction; * morbidly obese (weight \> 159 kg \[350 lbs\] or BMI \>42 kg/m2); * active malignancy at Screening. \[Treatment for basal cell or stage 1 squamous cell carcinoma, or cervical carcinoma in situ allowed\]; * terminally ill or has moribund condition; * history of irritable bowel syndrome, inflammatory bowel disease, ischemic colitis, vascular intestinal atherosclerosis, previous bowel resection, impaction, or similar gastrointestinal conditions; * currently taking Kayexalate® (sodium polystyrene sulfonate); * allergic reaction to Optison™ or Definity® or any of their components.