What is the stiffness index and what to do with it?
Imagine throwing yourself on an air mattress, or better yet, a water bed. Boom!
You're swinging on it, and it sways beneath you. Why does it happen?
You have created a wave that reflected from the bed walls multiple times and now travels under you, wiggling sensibly. You have created a wave in a closed space—and received part of it back after the wave bounced off the walls.
How quickly do we receive this reflected wave? If you stretch the water bed surface to make it firmer, the wave will toss you faster; vice versa, if you loosen the bed surface, it will sway slower. The stiffer the walls, the faster the wave bounces off them and returns to the source.
This is it! The heart is you, the vessels are the water bed. Boom! A portion of blood is ejected from the heart into the aorta—our main vessel, a wide tube with elastic walls (as the water bed walls). But like any other water-based liquid, blood is incompressible, while the walls of the aorta stretched and reflected part of the pulse wave (blood) back to the heart—just like a tennis net throws back a tennis ball. For this purpose, at the beginning of the aorta is a special valve that shuts and doesn't let blood get back. But some part of the wave always makes its way back to the heart, so it has to withstand the strike.
How strong and fast is this strike?
The stiffer the aorta walls (or the less elastic the vessels), the faster and stronger they reflect the pulse wave—the stronger striker the heart has to withstand. And vice versa, the more elastic the vessels, the longer it will take the pulse wave to pass through—the weaker it blows the heart before the valve shuts. The human heart makes 100,000-150,000 beats every day. And if the heart is even a little bit overloaded by this strike resistance, it turns into a significant burden if you multiply it by 100,000. I wouldn't like to have such a multiplier next to even the smallest equivalent of damage.
A few more things:
- The stiffness index changes as you age. As a person ages (especially after 40-50 years), the aorta gradually turns stiffer.
- Abnormal stiffness index growth is the earliest symptom of vascular conditions (indicating that unwanted substances intrude into the vascular wall) such as atherosclerosis. A high stiffness index accompanies type 2 diabetes and many other diseases.
- The stiffness index is likely to be false high in case of increased arterial pressure. It makes sense, since if more pressure is applied to an elastic tube, it becomes stiffer. You don't want to measure your stiffness index when you experience higher pressure. If you know you are prone to hypertension, be sure to measure your arterial pressure before testing; if the values are higher than normal, postpone the test until pressure returns to the good level. High blood pressure is itself a serious reason to take measures to control your health.
- It's safe to state that stiffness index changes bespeak biological changes in the body. Elastic, healthy vessels mean healthy life, and vice versa.
What should you do to keep your arteris in good health? See below, at the end of the next article.
Small vessel tone. What is it?
Imagine an apartment block with a plumbing system. Water comes to this building through a wide pipe.
Once it reaches the house, pipes branch, becoming thinner and thinner. Once the pipes get to apartments, they can't even be seen.
It's a powerful pump that pushes water into the house through a wider pump. The pump has to drive several tonnes of water a day—otherwise, sickness, thirst, and contamination will become a local plague in the house.
Our body is different from an apartment block, because:
- The human body is an apartment block with millions of apartments. It's way more intricate and complex: not a single architect could design a house like that.
- In the body, blood supply is regulated not by valves but by the vessel tone (contraction and extension). Our body regulates blood supply to all organs, to each cell—adjusting the vessel diameter and lumen. Your stomach needs blood in the afternoon and your muscles need blood when you work out. Vessels must extend or contract when needed.
Managing such a pipeline in a house with a billion apartments is extremely difficult even at rest. When taps in all "apartments" and "staircases" are properly regulated, everything goes normal. Now imagine that valves in some apartments failed and water can barely pass through. Anyway, the pump has to deliver the required volume to the house, or the citizens (our cells) will get sick and die (what they often do). Meanwhile, the house resists the water flow: valves are shut, the pipe diameter management system is disturbed. The pump does it best, as long as it can, keeping driving the flow across the body. It does 100-150 thousand thrusts every day. The pump wears out, and the pipes—under higher pressure and stress—break more and more often.
The small vessel tone index reflects the condition of the "pipeline management system", a complex, multi-layer mechanism. Based on the small vessel tone index, the vessel age is determined. It's great when the vascular age matches, or is lower than, the passport age.
Here's what you need to know about your small vessel tone index:
- To assess the small vessel tone, you need to monitor the vascular age. You're good if the vascular age matches, or is lower than, the passport age. It's normal if these values match; but if the vascular age exceeds your biological age by 10 years or more, you may want to see a doctor.
- The small vessel tone may, for different reasons (disorder, stress, smoking, purulent processes, dental problems, etc.), change significantly even in young patients.
What to do to keep arteries and the heart healthy?
The common method is well-known: you need to live a healthy life:
- Move enough (~10,000 steps or an hour walking a day).
- Control your physical load.
- Maintain emotional hygiene. What does it mean? Encourage positive emotions, create favorable conditions for them. Avoid such feelings as envy, anger, resentment, and irritation.
- Manage your stress.
- Don't smoke (just for an experiment, perform a test before and after smoking a cigarette).
- Adhere to a healthy diet: consume greens, oily fish, tea (green or black, but if possible, "real"), nuts, chocolate, dried fruits, good alcohol (limit it to the minimum to avoid the reverse effect).
- • Last but not least, remember that every person has unique characteristics and features.