Located almost in the center of the chest, the adult human heart is about the size of two fists held side-by-side.

The two blood pressure numbers indicate how much pressure builds up in the arteries as the heart beats and between beats.

High blood pressure, or hypertension, increases the risk for coronary heart disease (heart attack) and stroke (brain attack).

If you have high blood pressure, you need to know, so you can control it. If you don't, you increase your risk for serious illness.

Prehypertension is a new term that alerts people to the risk of developing chronic high blood pressure if they don’t take timely steps to improve their lifestyle habits.

In many cases, the progression to high blood pressure occurs within four years of being diagnosed with prehypertension.

Hypertension, or high blood pressure, isn't limited to those 18 and older.

Doctors often consider chronically low blood pressure too low only if it drops suddenly or causes noticeable symptoms.