The aim of this study is to evaluate whether penile peak systolic velocity (PSV) varies in patients with erectile dysfunction (ED) due to artery insufficiency associated with abnormalities in other arterial districts or not. To accomplish this, cavernous artery PSV was determined 10, 20 and 30 min after intracavernously administering alprostadil by means of echo-color Doppler to a total of 65 consecutive patients (age range 52-78 years). In all, 18 patients had ED alone (group A) and served as controls, 15 had ED plus atheroma plaques and/or marked intima-media thickness of the common carotid artery (group B); 17 had ED plus lower limb artery abnormalities; 17 had ED plus carotid and lower limb artery abnormalities (group D). Group B and C patients had a similar PSV, which turned out to be significantly lower than that in group A. Group D patients had the lowest PSV, which proved to be significantly lower than that in groups A, B and C. This study shows that a more generalized peripheral atherosclerotic process is associated with a severer penile artery insufficiency. Therefore, ED patients with a severe arterial insufficiency should undergo an extensive echo-duplex examination.