title: Effect of sildenafil citrate (Viagra) on coronary flow in normal subjects.
abstract: BACKGROUND
  The purpose of this study was to evaluate the effect of sildenafil citrate (Viagra) on coronary function in normal subjects.
  
  
  METHODS
  The study assessed mean blood pressure, left anterior descending coronary artery (LAD) flow, and echocardiographic variables before and 30 and 60 minutes after taking 50 mg of sildenafil citrate. The mean velocity of LAD flow was assessed with Doppler flow imaging. The study subjects were 6 healthy male volunteers (mean age 37 years).
  
  
  RESULTS
  The mean velocity of LAD flow increased 60 minutes after taking sildenafil citrate, but there were no other changes. Two volunteers felt mild flashing and one had mild headache during the study.
  
  
  CONCLUSIONS
  Sildenafil citrate caused vasodilatation in a normal coronary artery without systemic pressure drops. These results suggest that the agent itself did not have negative effects on the heart in normal subjects.
authors.affiliation: School of Allied Health Sciences, Osaka University, Faculty of Medicine, Osaka, Japan. ishikura@sahs.med.osaka-u.ac.jp
authors.forename: Fuminobu
authors.initials: F
authors.lastname: Ishikura
authors.forename: Shintaro
authors.initials: S
authors.lastname: Beppu
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ueda
authors.forename: Ajay
authors.initials: A
authors.lastname: Nehra
authors.forename: Bijoy K
authors.initials: BK
authors.lastname: Khandheria
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects*; D015150:Echocardiography, Doppler; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D011687:Purines / Q000494:pharmacology; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate