Hypertension or high blood pressure is the excess pressure of blood on the walls of arteries. Arteries are vessels that carry blood from the pumping heart to all the tissues and organs of the body.
Normal blood pressure is less than or equal to 120/80; blood pressure between 120/80 and 139/89 is called "pre–hypertension", and a blood pressure higher than140/90 is considered high and may be called hypertension
The first number, 120 is the systolic blood pressure and corresponds to the pressure in the arteries as the heart contracts and pumps blood forward into the arteries. The second number, the diastolic pressure, represents the pressure in the arteries as the heart relaxes after contraction.
An elevation of blood pressure increases the risk of damage of the following organs:
These damages are called complications of hypertension. As a result of long term (chronic) hypertension, the ultimate result of the complications is damage or functional failure of the respective organ or tissue. The end-organ damage, for example could be blindness (eyes), stroke (brain) heart disease (heart) etc. For avoiding all these complications, it is essential to detect hypertension as early as possible and take steps to normalize your blood pressure by various means.
Scientists earlier thought that diastolic hypertension was riskier than diastolic one, but it is now known that in people older than 45- 50 years systolic hypertension poses a greater risk.