Statistical evaluation of hemodynamic effects of regular use of sildenafil on the human corpora cavernosa

INTRODUCTION: Sildenafil citrate is currently used on demand in the treatment of erectile failure, regardless of etiology. Nevertheless, recent data suggest a significant improvement in nocturnal penile erections in potent and impotent men taking a single dose at bedtime. The present study analyzes whether continuous use of sildenafil positively correlates with improvement of penile blood flow and treatment satisfaction referred by patients with erectile dysfunction (ED) of vascular origin. PATIENTS AND METHODS: A total of 32 patients, mean age 54, with ED of vascular etiology, were evaluated at the beginning and at the end of our study using the International Index of Erectile Function (IIEF-5) and pharmaco-penile duplex ultrasonography during basic and dynamic phases. These patients were treated with sildenafil (50 mg) twice a week for 4 months. During pharmaco-penile duplex ultrasonography, we measured basal peak flow velocity, basal acceleration of peak flow in both cavernous arteries before intracavernous (i.c.) pharmaco-stimulation, maximum peak flow velocities and end-diastolic flow velocities after i.c. stimulation. The data observed were compared with those of 10 patients with ED who voluntarily decided not to take any treatment. RESULTS AND CONCLUSIONS: In this study, basal peak flow velocity, basal acceleration, maximum peak flow velocity and IIEF-5 scores were found to significantly increase after treatment. All differences were statistically significant (p < 0.05). Only few mild adverse effects were observed. Our data suggest that the regular use of sildenafil (50 mg) improves the blood flow in cavernous arteries increasing sexual performance in patients with ED of vascular origin.