Dr. Bailey posted on January 11th, 2017
Your heart is a small four-chamber muscle pump that circulates blood throughout your body. Blood is pumped out through a wide blood vessel called the aorta which serves as a main highway strip leading to smaller and smaller roadways (vessels) throughout your body. This highway system allows blood to reach body parts such as your brain, kidneys, reproductive organs, muscles, hands, and feet.
A certain amount of pressure within these tubes or pipes is normal. However when the pressure gets high this can stress the walls of the pipes and cause the heart to work harder to pump blood out with each beat. Think of it as a mover having to push harder against a box if someone else is on the other side pushing against it. If this goes on the hearts structure can change over time in ways that can limit its ability to even pump at all. Examples of harmful changes are muscle stiffening and overstretching of the heart’s chambers.
So back to the original question…what is blood pressure? Blood pressure is simply the force or pressure against the walls of your blood vessels. This force is measured in millimeters of mercury (mm Hg) just like air or barometric pressure on the weather report. This force is highest when the heart pumps out blood (systole) and lowest when the heart relaxes between heart beats (diastole). The blood pressure reading is the estimated maximum (systolic) pressure and minimum (diastolic) pressure. For example a max pressure of 130 mmHg and minimum pressure of 80 mmHg is stated as "130 over 80" or written as 130/80 mmHg.
Normal blood pressure for adults is 120/80 mmHg or a little bit less. A top number of 120-139 or a bottom number of 80-89 is in the "danger zone" for high blood pressure. This state is called pre-hypertension. Any higher numbers on two or more different blood pressure checks likely means you have high blood pressure (hypertension).
The exact cause of someone's high blood pressure is usually not obvious. Issues such a bad sleep patterns, high salt diet, stress, smoking, heavy alcohol use, recreational drug use, kidney problems, hormone disorders, being overweight, and certain medications are known culprits. Genetics can also play a role which is part of why high blood pressure runs in some families. Occasionally special lab tests and body imaging (e.g., MRI) will reveal the cause.
So why is your blood pressure reading important? Sustained pressure elevation in pipes causes the inner lining to become inflamed, hard, and stiff. Fat in your blood can collect at areas of pipe wall damage. Altogether these changes result in plaques along the pipe walls and choke off room for blood flow. Circulation to the brain, eyes, heart, kidneys, penis, vaginal area, calves, and feet can be decreased. Pieces of wall plaques can rupture resulting in the formation of blood clots that can chip off, travel in the blood stream, and become lodged at other locations, blocking blood flow to organs like the heart (heart attack) and brain (stroke). The high pressures along with weakened vessel walls can lead to breakage of small pipes (vessels) all over the body in places like the brain, kidneys, and the back of the eye; causing dysfunction in each of these areas. These are some of the reasons high blood pressure is called a silent killer.
It is important for those with high blood pressure to have periodic doctor visits, bloodwork to check items such as kidney function, and a yearly dilated eye exam. If you have blood pressure issues or just general questions then you should check-in with your doctor.
-- Dr. Westly Bailey