Why Are Men Who Have a Heart Condition Warned Not

Why are men who have a heart condition warned not to take Viagra?

A) Viagra can cause the build up of plaque in the arteries leading to another heart attack.
B) Viagra closes down the arteries to the heart to shunt the blood supply to the penis.
C) Viagra increases blood flow to the penis in order to promote an erection and this could have an effect on the rest of the cardiovascular system.
D) Viagra shuts down the immune system in order to trick the body in to sending more blood to the penis and this can open up the heart to increased infection rates.
E) Viagra slows the beating of the heart and this could result in a heart attack.