An important factor in whether you pay the price for your dietary indiscretions sooner, rather than later, is how carefully you chose your parents.

But seriously, folks.

Atherosclerosis emphasizes the material that clogs the vessels, a whitish, cheesy stuff officially called "atheroma."
Arteriosclerosis emphasizes the place where the clog is, namely the arteries.

As commonly used, there's a huge overlap between the two conditions.