Hypertension, also known as High Blood Pressure, is a condition in which the blood vessels have persistently raised pressure, putting them under increased stress. Each time the heart beats; it pumps blood into the vessels, which carry the blood throughout the body. Blood pressure is created by the force of blood pushing against the walls of blood vessels (arteries) as it is pumped by the heart. The higher the pressure, the harder the heart has to pump.
If Diastolic is above 140 mmHg and Systolic is < or equal to 80, it is called Isolated Diastolic Blood Pressure.
If Diastolic is around 120 mm Hg and Systolic is above 90 mm Hg, it is called Isolated Systolic Blood Pressure.
Normal adult blood pressure is defined as a blood pressure of 120 mm Hg when the heart beats (systolic) and a blood pressure of 80 mm Hg when the heart relaxes (diastolic). When systolic blood pressure is equal to or above 140 mm Hg and/or diastolic blood pressure equal to or above 90 mm Hg the blood pressure is considered to be raised or high. In Hypertension both Systolic and Diastolic values are above the normal.