Your heart pumps blood through your arteries, and the force this creates on your arteries is called your blood pressure. Blood pressure is measured by counting your pulse when a cuff is tightened around your arm, and again when it is loosened. This gives you two blood pressure numbers: systolic, that measures blood pressure when your heart contracts, and the much lower diastolic, when your heart relaxes.

When your heart contracts, it pushes a huge amount of blood forward to your arteries. Your arteries are supposed to act like balloons and expand to accept the blood and prevent your blood pressure from rising too high. Having plaques in your arteries stiffens them and prevents them from expanding when your heart contracts, causing your blood pressure to rise higher than normal. The stiffer your arteries become, the higher your blood pressure rises. The intense pressure on artery walls from high blood pressure can cause damage that provides ideal places for even more plaque to accumulate. It