Blood pressure readings are often used as a way of assessing the overall health of the cardiovascular system. Blood pressure readings reflect the health of both the heart and arteries throughout the body; abnormal readings may be a sign of an underlying health problem.
Normal Measurements
Blood pressure is divided into the systolic pressure, which is the arterial pressure when the heart is beating and the diastolic pressure, which is the pressure when the heart is resting. Normal blood pressure measurements are a systolic pressure below 120 and a diastolic pressure below 80 mm of mercury, the American Heart Association explains.
Elevated
Blood pressure measurements above the normal can be divided into pre-hypertension, hypertension stage I, hypertension stage II and hypertensive crisis. A systolic pressure of between 120 and 129 or a diastolic pressure in the 80s is prehypertension. Stage I hypertension is a systolic reading between 130 and 149 or a diastolic pressure in the 90s. Anything above that is considered to be stage II hypertension. A hypertensive crisis is a systolic pressure above 180 and a systolic pressure above 110 and requires immediate medical attention.
Low Blood Pressure
In general, abnormally low blood pressure is a systolic pressure below 90 or a diastolic pressure below 60 mm of mercury, MayoClinic.com reports. This can be due to dehydration, blood loss, an infection or other problems. Some people have naturally low blood pressure numbers, however.
