Blood pressure is a basic vital sign showing the overall status of the heart and circulatory system. Although its measurement has become so familiar to all of us, we only figured out how to measure it 100 years ago, and measure it painlessly much more recently.
One needs a little anatomy lesson to understand blood pressure. The heart pumps blood intermittently, contracting then refilling – about once per second. Like a Harley-Davidson twin engine, valves make sure the blood flows one direction only.
The arteries have muscular walls and stretch to accommodate the pulse of blood. They steadily recoil to convert the pulsatile flow into a continuous one. Although blood flows continuously, a pressure wave occurs with every forceful heartbeat.
That pressure is highest when the heart contracts and is lowest right before the next contraction. This was initially investigated using a direct approach – a surgical procedure. A pressure gauge was inserted directly into a major artery, which is not something the average patient would sit still for these days.
A considerably easier way to measure blood pressure is the modern-day inflatable cuff and stethoscope. The cuff is placed on the upper arm and uses air pressure to squeeze the upper arm until there is no sound heard over a downstream artery. That takes place because the pressure on the arm is greater than in the artery.
The pressure at which blood just starts getting through is identified by the start of a knocking sound. That is the highest, or systolic, pressure. The pressure when the knocking sound goes away is the diastolic, or lowest pressure. These two numbers are conventionally written as the systolic/diastolic pressure (120/80).
Why do we care what our blood pressure is as long as the blood continues to go round and round? Blood pressure controls many factors, and one of the main ones is the flexibility (compliance) of the arteries in the system. If those arteries “harden” (become injured and have calcium deposits in the walls), the blood pressure goes up substantially.
Many things can contribute to atherosclerosis, or hard, inflexible arteries. Diabetes, high cholesterol, smoking, obesity, poor diet, genetics, and stress, among others. Of course, the harder the blood vessels get, the higher the blood pressure, which also contributes to atherosclerosis. So hypertension is both a cause and a result of blood vessel disease.
As these predatory risk factors tend to run in packs, we call them “metabolic syndrome.”
Since bad arteries are the basis for almost half the deaths in our country, including those caused by Alzheimer’s, heart attacks, strokes, and renal failure – it is worth avoiding them, which is not rocket science.
Below are some recommendations:
- Stop smoking: This is the single, strongest cause of artery disease.
- Become more active: It helps your blood vessels stay in good shape or even heal. Everything counts, park farther away, take the stairs, be inconvenienced.
- Think about what you eat. Unless you eat heavy metals (lead, arsenic), animal fat is the worst thing you probably eat.
- Check your cholesterol, blood sugar, and blood pressure: All are correctable with lifestyle or medical changes.
It is only February, so there is time to make changes.
Donald Bucklin, MD (Dr. B) is a Regional Medical Director for U.S. HealthWorks and has been practicing clinical occupational medicine for more than 25 years. Dr. B. works in our Scottsdale, Arizona clinic.
Photo of man running courtesy of Maarten van den Heuvel via Unsplash.