title: Understanding congestive heart failure (CHF).
mesh_terms: D000222:Adaptation, Physiological; D000367:Age Factors; D001775:Blood Circulation; D000075202:Contraindications; D003863:Depression / Q000209:etiology; D006333:Heart Failure / Q000145:classification / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D010879:Piperazines; D011687:Purines; D012131:Respiratory Insufficiency / Q000209:etiology; D018570:Risk Assessment; D000068677:Sildenafil Citrate; D013450:Sulfones; D014665:Vasodilator Agents
chemical_list: D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate