title: Letter: What is "refractory" cardiac failure?
mesh_terms: D004071:Digitalis Glycosides / Q000627:therapeutic use; D004077:Digoxin / Q000627:therapeutic use; D004232:Diuretics / Q000627:therapeutic use; D006333:Heart Failure / Q000188:drug therapy*; D006801:Humans
chemical_list: D004071:Digitalis Glycosides; D004232:Diuretics; D004077:Digoxin