What does hardening of the arteries signal?

Hardening of. It means that ones arteries have become stiff due to a process known as "atherosclerosis" happens over a period of time.It usually applies to coronary arteries.Which could mean a future heart attack.
Signals many things. It signals an increased risk of heart attack, stroke and poor circulation to the limbs. It signals that it is time to make healthy life style changes. It signals that you should see your doctor and set goals to prevent or control diabetes and keep cholesterol and blood pressure below recommended levels.