How does the vascular system play a role in impotence?

Absolutely: The vasular system is extremely important in regards to all aspects of body function, especially with erectile dysfunction. Many conditions impair blood supply to the penis which leads to impotence. Such problems include diabetes, hypertension , and elevated cholesterol levels.

Erection=more flow: An erection is having an increase in blood flow that both fills the spongy rods of the penis (making them hard) and blocks the outflow of blood (keeping them hard). Erectile dysfunction (ed) is impotence, or inability to maintain the erection. Things that damage blood flow increases(smoking, hypertension, high lipids, scarring of rods etc) or the nerves that control flow(diabetes etc) are to blame.