Although vardenafil is widely prescribed for erectile dysfunction (ED), its effect on arterial function is not defined. Aortic stiffness, aortic pressures, and wave reflections are predictors of cardiovascular risk. The investigators assessed the hypothesis that vardenafil acutely improves aortic stiffness, aortic pressures, and wave reflections in ED patients. Twelve ED patients (mean age 58 ± 9 years) received vardenafil 20 mg in a randomized, placebo-controlled, double-blind, 2-way crossover design. Aortic stiffness was evaluated with carotid-femoral pulse wave velocity (PWV); wave reflections and aortic pressures were evaluated with augmentation index (AIx) and systolic, diastolic, and pulse pressure of the aortic pressure waveform, respectively. PWV, aortic pressures, and AIx were measured at baseline and for 3 hours after vardenafil intake or placebo. PWV decreased significantly (by 0.7 m/s, P = .001), denoting a decrease in aortic stiffness. AIx decreased significantly (by 7%, P = .008), denoting a decreased effect of wave reflections from the periphery. Aortic pressures decreased significantly (all P < .05). Statin use at baseline significantly interacted with the effects of treatment on both PWV and AIx (P = .003 and P < .001, respectively). This study shows, for the first time, that vardenafil has a favorable acute effect on aortic stiffness and wave reflection in ED patients.