Study With Omecamtiv Mecarbil (CK-1827452) to Treat Chronic Heart Failure With Severely Reduced Ejection Fraction

Inclusion Criteria: Adult patients who meet all the following criteria at screening may be included in the study: * Are between ≥ 18 years and ≤ 85 years at the signing of informed consent * Have a history of chronic HFrEF, defined as requiring treatment for HF for a minimum of 3 months prior to screening * Are receiving oral loop diuretics on a regular schedule * Patients without AFF on screening ECG: * LVEF \< 30% within 6 months of screening * Elevated N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) ≥ 1000 pg/mL (BNP ≥ 300 pg/mL) * Patients with AFF on screening ECG: * LVEF \< 25% within 6 months of screening * Elevated N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) ≥ 3000 pg/mL (BNP ≥ 900 pg/mL) * Not currently taking digoxin * Meet one of the following criteria for a recent HF event: * Are currently hospitalized with the primary reason of HF * Had an HF event (as defined in the primary endpoint) within 12 months prior to screening. For the purposes of a qualifying HF event, subcutaneous furosemide will be treated as equivalent to intravenous furosemide Or * Had outpatient escalation of oral diuretics due to worsening signs and symptoms of heart failure plus one of two additional criteria sustained for at least 1 week: (1) at least 50% or 1.5-fold increase in daily loop-diuretic-equivalent dose; (2) the addition of a new diuretic class to a loop diuretic. * Are established on regional standard-of-care HF therapies for …