- Subject on stable* optimal pharmacologic therapy for the cardiac condition that is guideline-based and may include one or more of the following medications: Loop diuretics (e.g., furosemide, bumetanide, torsemide) unless the subject is not indicated, is contraindicated, or is intolerant of loop diuretics; Angiotensin converting enzyme (ACE) inhibitors and/or angiotensin receptor blocker (ARB) unless the subject failed, is not indicated, or is contraindicated for these therapies; Aldosterone antagonists unless the subject is not indicated, or is intolerant of aldosterone antagonists; Beta-blockers unless the subject is not indicated, contraindicated, or is intolerant of beta-blockers. The choice of selective or non-selective beta-blockers use is left to the Investigator's discretion * For purposes of the study, "stable" is defined as beta blockers and ACE/ARB for at least three months prior to randomization, unless contraindicated or not tolerated, with stable doses for at least one month prior to randomization. It is permissible for diuretic and aldosterone antagonist dosage to have been adjusted as necessary.