title: Viagra is safe for some men with heart disease.
mesh_terms: D006331:Heart Diseases / Q000150:complications; D006334:Heart Function Tests / Q000379:methods*; D006801:Humans; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects*; D010879:Piperazines / Q000009:adverse effects*; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate