Blood pressure is a measure of the force exerted by circulating blood on the walls of the arteries as it flows through them. Pure blood carrying oxygen and other vital nutrients is pumped by the heart into the arteries and is circulated all over the body. The pumping action of the heart and flexibility of the arteries forces the blood to exert a certain pressure on the walls of blood vessels. This blood pressure is regulated mainly by the response given by arteries to the flow of blood.

Understanding Systolic and Diastolic Blood Pressure
Blood pressure is one of the vital signs of life. It is normally expressed as two numbers, the first or the upper number indicating the systolic blood pressure, and the lower number indicating diastolic blood pressure.

Systolic blood pressure represents the pressure exerted by the blood on the arteries when the muscle of the heart contracts and pumps blood through the blood vessels to the rest of the body. This is the maximum pressure exerted by the blood on the arteries.

Diastolic blood pressure refers to the pressure exerted by the blood when the heart is at rest in between contractions. 120/80 mm Hg or a little lower, is considered as an ideal blood pressure for a healthy adult, where 120 mm Hg stands for systolic pressure and 80 mm Hg for diastolic pressure.

So What is Low Systolic Blood Pressure?
Systolic blood pressure is the highest pressure that is exerted by the blood, towards the end of a cardiac cycle.

The average range of systolic blood pressure is between 90 to 119 mm Hg. Anything below 90 mm Hg is considered as low blood pressure. Generally, low blood pressure is characterized by a decrease in both the systolic as well as diastolic blood pressure.

However, it may happen sometimes that your diastolic pressure is near normal, but your systolic pressure has lowered. This condition is referred to as systolic hypotension and is mainly defined by signs and symptoms, rather than a specific blood pressure reading.

A person having 90 mm Hg as his systolic pressure may show signs of low blood pressure, whereas another person with the same BP reading may be extremely normal.

For healthy people, especially athletes, low systolic pressure may be a sign of good cardiovascular health, whereas the same can indicate an underlying problem in others. It may indicate that the heart is unable to pump enough blood and result in organ failure.

Causes of Low Blood Pressure
Loss of blood due to serious head injury or trauma
Dehydration or loss of fluids in the body
Overdose of certain blood pressure controlling drugs
Heart diseases
Acute illness that causes damage to the heart or blood loss
Inadequacy of important nutrients in the diet

Chest pain
Shortness of breath
Organ failure

Treatment mainly depends on the cause. For example if your blood pressure has been lowered due to dehydration, it can be treated with fluids and minerals (electrolytes). Blood loss-related low blood pressure can be treated with intravenous fluid and blood transfusion. Hence, it is very important to identify the exact cause for an effective treatment.

It can be simple to identify the symptoms of this cardiovascular disorder. However, if not identified at an early stage, it can cause serious effects like a heart attack.