What's the youngest age you can get heart disease?

Heart disease use to be mostly an adult health problem because of years of smoking, drug addiction, having high blood pressure, being overweight, cholestrol, stress and other factors that come with wear and tear on the body. Heart disease is starting to be more common in kids that are over weight and have poor diets. I really don't know the youngest age but it is rarer in kids than adults. The most common age it starts is usually late 30's early 40's.