Why Do Arteries Get Clogged? It’s Not What You Think

Aug 18, 2023

Why Do Arteries Get Clogged? It’s Not What You Think

Heart disease is the number one killer in the world. To understand why this disease is so deadly, Patrick has some answers for you.
» Subscribe to Seeker! http://bit.ly/subscribeseeker
» Watch more Human! http://bit.ly/HUMANplaylist
» Visit our shop at http://shop.seeker.com

To start, the term cardiovascular disease actually includes a bunch of different diseases, and there are many factors that go into what causes each kind. And the structure we need to learn to understand these diseases isn’t necessarily the heart, but rather the arteries.

Arteries are complex, ever changing organs that deliver blood throughout the body and play a role not just in disease, but in experiencing different climates, exercising, and maintaining homeostasis.

When you take a big picture look at the entire cardiovascular system, you will see two distinct loops of blood vessel networks, shaped like a figure eight. One of the loops carries deoxygenated blood from the right side of the heart to the lungs, picks up some oxygen, and circles back to the heart.

This pulmonary circulation is where important gas exchange happens, allowing us to utilize all the carbon dioxide waste we’ve built up in our blood and capture that oxygen we breathe in.

Once our blood is nice and oxygenated it comes back to the left side of the heart to be pumped into systemic circulation, the second loop that hits everything that isn’t the lungs.

Right after getting ejected from the left side of the heart, blood then passes through the aorta, which is the biggest artery the human body has.

The aorta branches off into smaller arteries up into the neck and brain and down the body into the limbs and abdomen. As the arteries get closer to individual tissues and organs, they’ll branch off into tiny arterioles, and then into microscopic blood vessels called capillaries.

Some of those capillaries are so tiny that red blood cells have to line up cell by cell to get through.

But, no surprise, not all of our arteries are built the same.

Find out more about your different arteries, the purposes they serve, and how they all come up again and again when it comes to understanding cardiovascular disease in this episode of Human.

#cardiovascular #disease #arteries #humanbody #human #seeker #science

Read More:
The top 10 causes of death
https://www.who.int/news-room/fact-sh…
“Of the 56.9 million deaths worldwide in 2016, more than half (54%) were due to the top 10 causes. Ischaemic heart disease and stroke are the world’s biggest killers, accounting for a combined 15.2 million deaths in 2016. These diseases have remained the leading causes of death globally in the last 15 years.”

Nanoparticle helps eat away deadly arterial plaque
https://newatlas.com/medical/nanopart…
“Atherosclerotic plaque-deposits on the inner walls of arteries are a frequent cause of heart attacks and strokes. A newly-developed nanoparticle could help minimize those deposits, as it prompts the body’s own cells to “eat” them.”

Mystery of why arteries harden may have been solved, say scientists
https://www.theguardian.com/science/2…
“The mysterious mechanism behind the hardening of arteries may have been solved, researchers have revealed, in a study that also suggests the first potential preventive drug for the condition linked to heart attack, dementia and stroke. Arteries harden as calcium becomes deposited in the elastic walls of the vessels, a process that happens as we age and is exacerbated for patients with diabetes or kidney disease.”

This Seeker health miniseries will dive deep into the cellular structures, human systems, and overall anatomy that work together to keep our bodies going. Using the visual structure and quick pacing of Seeker’s Sick series, these human bio-focused episodes will give a new audience an inside look on what’s happening inside all of us.

Visit the Seeker website https://www.seeker.com

Seeker on Facebook https://www.facebook.com/SeekerMedia/

Focal Point on Facebook https://www.facebook.com/FocalPointShow/

Seeker on Twitter http://twitter.com/seeker

Content

0.16 -> Cardiovascular disease has been the number one killer in the world for over a decade

4.399 -> and statistically, it’s the number one most likely thing to kill me, so I’m definitely

9.36 -> interested in learning more about it. It brings to mind one phrase you may have heard now

13.259 -> and then, “clogged arteries.” And I’m going to be completely honest, before I got

17.33 -> to college and learned the mechanism behind this disease, I thought clogged arteries were

22.029 -> a direct result of diet. Like if I put too much butter on my potatoes, that butter was

26.87 -> clogging my arteries. But it turns out that’s not what happens. The term Cardiovascular

31.529 -> disease is a catch-all for a bunch of different diseases, and there are a ton of factors that

35.829 -> go into what causes each kind. But the structure we need to learn to understand these diseases

41.14 -> isn’t the heart necessarily, it’s those arteries. These things are complex, ever

45.01 -> changing organs that deliver blood throughout the body and play a role not just in disease,

49.34 -> but in experiencing different climates, exercising, and maintaining homeostasis.

58.38 -> In the last few videos, we’ve been talking about the components of blood,

60.88 -> which includes a bunch of specialized cells.

63.48 -> We’ve got red blood cells for carrying and delivering oxygen to hungry body parts,

67.64 -> and the white blood cells that make up a big part of our immune system. But we haven’t

71.66 -> talked about the hardware that contains them and moves them. That’s where the cardiovascular

76.5 -> system comes in. If you prefer calling it the circulatory system, that’s fine too

80.36 -> — they’re the same thing. In this video, I’ll use cardiovascular because the name

85.45 -> gives away its pieces: the heart, hence the cardio portion, and all the blood vessels,

89.96 -> which is the vascular part. Now, the heart is an incredibly complex organ and we could

94.3 -> dedicate an entire series to it, but for now, we’re going to focus on the blood vessels,

99.36 -> those tubelike structures that transport blood around the body. When you take a big picture

104.17 -> look at the cardiovascular system, you’ll notice two distinct loops of blood vessel

108.71 -> networks, like a figure eight. One of those loops carries deoxygenated blood from the

112.97 -> right side of the heart to the lungs, picks up some oxygen, and circles back to the heart.

117.39 -> This loop’s pretty straightforward, only one organ to visit. This pulmonary circulation

121.71 -> is where important gas exchange happens, letting us do something with all the carbon dioxide

126.02 -> waste we’ve built up in our blood and capture that oxygen we breathe in. Once our blood

130.61 -> is nice and oxygenated it comes back to the left side of the heart to be pumped into systemic

134.81 -> circulation, the loop that hits everything that isn’t the lungs. As you can imagine

138.86 -> from the everything about this, the systemic circulation has a little more going on. Right

143.891 -> after getting ejected from the left side of the heart, blood passes through the aorta,

147.98 -> the biggest artery we have. This artery is going to branch off into smaller arteries

152.06 -> up into the neck and brain and down the body into the limbs and abdomen. As they get closer

157 -> to individual tissues and organs, they’ll branch off into tiny arterioles, and then

161.361 -> into microscopic blood vessels called capillaries. Some of those capillaries are so tiny that

165.56 -> red blood cells have to line up cell by cell to get through.

172.14 -> Not all of our arteries

173.33 -> are built the same. Big arteries close to the heart, like the aorta are under a lot

177.43 -> of pressure. And I don’t mean their parents are hovering over their shoulder checking

180.64 -> their math homework, I mean physical pressure from the pumping heart muscle. To cope with

184.88 -> this pressure, they’re built to be more elastic, letting them expand along with the

189.11 -> pressure. As we get to the arteries of the arms and legs, we see them become more muscular,

193.93 -> giving them more control of their diameter. This is where we start seeing the arteries

198.05 -> as more than just static tubes. An artery itself has three main layers, or tunics: the

202.9 -> tunica externa, media, and intima. Literally the outer, middle, and inner layers of the

208.37 -> artery. They all serve a different purpose, and they all come up again in understanding

212.72 -> cardiovascular disease. The tunica externa, also called the adventitia, gives the artery

217.7 -> its general shape and structure. The tunica media is built of a protein called elastin,

222.27 -> which, as you could tell by the name, gives the artery some elasticity. But it’s also

226.79 -> got a layer of contractible muscle around it. Now, this is a different type of muscle

231.39 -> from the skeletal muscles in your arms and legs. This smooth muscle surrounds the entire

236.1 -> blood vessel which provides a little more support, but more importantly, it regulates

240.15 -> how wide the artery becomes. Why is this so important? Well, the ability to shrink or

245.03 -> expand our blood vessels comes in handy in different situations. Let’s take a look

249.82 -> at exercise for example. Right now, you’re at rest. Your heart is probably beating nice

254.44 -> and steady — around sixty to a hundred beats per minute. At that rate, about five liters

258.709 -> of blood will pump out of your heart in the next sixty seconds. That’s enough to feed

262.7 -> all of your oxygen-hungry tissues at rest, but they get hungrier when you exercise. So

267.991 -> in order to ship more oxygen to those tissues, your body increases its heart rate, or how

272.47 -> frequently your heart pumps, and stroke volume, the amount of blood squeezed out with each

276.96 -> pump. For most of us, that means the five liters of blood we were pumping every minute

281.11 -> at rest can get up to thirteen liters a minute at peak exercise, and even more if you’re

286.07 -> a trained athlete. That means your arteries have to adjust for two and half times more

290.2 -> blood volume coming through. They do so by vasodilating — the smooth muscle of the

295.18 -> tunica media relaxes, which expands the diameter inside the blood vessel. In a totally different

300.63 -> situation, your arteries can vasoconstrict as a way to reduce loss of body heat and stay

304.889 -> warm in cold temperatures. Those changes in diameter are all possible thanks to the tunica

309.94 -> media, but there’s still one more layer to arteries. The innermost layer, or tunica

314.58 -> interna, has a little more smooth muscle and elastin, but most importantly, it’s lined

319.29 -> with super smooth endothelial cells. These cells have a very important job — provide

324.6 -> a low friction surface and make sure blood gets through circulation as smoothly and efficiently

328.88 -> as possible. So all in all these arteries have a thick outer layer, a smooth inner layer,

334.48 -> and a middle layer that changes the diameter of the vessel, which is amazingly useful.

338.59 -> All of this sets us up to understand how we can go from a free flowing, smooth blood vessel

343.699 -> to a “clogged artery”. Okay, so this process isn’t something that happens all at once.

348.55 -> Arteriosclerosis is the buildup of plaque within an artery to the point where it interferes

352.42 -> with normal function, and it can happen in any artery. Some of these conditions get

356.88 -> names with a little more pizazz though, a little more oomph where you’re like “ohh

360.24 -> dang, I don’t want that” but the pathogenesis is the same. Like when the arteries to the

364.6 -> brain get blocked, we call that a stroke or when the arteries to the heart muscle get

368.22 -> blocked we call that a heart attack. And when those organs don’t get blood, they don’t

372.82 -> get oxygen, and that can cause severe damage or sometimes death.

378.34 -> There are a few different

379.32 -> ways it can begin, but at some point, the endothelial cells become dysfunctional. Remember

384.24 -> from earlier, this layer’s job is to be as smooth as possible so blood can just flow

388.7 -> through. And a bunch of different factors make this condition more likely — smoking,

392.949 -> high blood pressure, diabetes all predispose an artery to endothelial dysfunction.

397.8 -> For instance, smoking reduces the availability of nitric oxide, a chemical that allows the

402.62 -> blood vessels to vasodilate, and increases some inflammatory factors that make the blockage

407.24 -> even worse.

412.5 -> But no matter what causes the dysfunction, now the endothelium lets lipids

416.74 -> from the blood sneak under that layer of endothelial cells and into the intima. That starts a process

422.48 -> where immune cells are called to the scene, where they enter the intima and oxidize those

426.52 -> lipids into foam cells. Foam cells sound cute, but these things are serious. Those immune

431.97 -> cells also recruit more smooth muscle to the area, as well as the tough connective tissue

436.259 -> collagen, which is definitely not supposed to be there. As a result, instead of a soft

440.96 -> bump you’ve got a tough, fibrous plaque. That cycle of plaque stacking can continue

445.39 -> until blood can barely get through an artery and that’s when the tissues it supplies

448.86 -> oxygen to really start to suffer. So again, clogged arteries are the narrowing of arteries

453.72 -> from plaque buildup and not some kind of buttery cholesterol fatberg in your blood vessels.

458.3 -> But that doesn't mean it's not dangerous. That plaque can break open, which means now there’s

462.759 -> a blood clot free floating in your arteries. That’s why a narrowing of the arteries around

466.72 -> the heart is so deadly. If that loose blood clot gets stuck on some plaque in those arteries,

471.759 -> oxygen can’t get to the heart muscle itself and it can die off. And that’s a heart attack.

476.509 -> This is one of the reasons why healthcare professionals recommend exercise for preventing

480 -> heart disease. It has the ability to reduce chronically high blood pressure and lower

483.66 -> bad cholesterol, but it also improves your ability to produce nitric oxide, that vasodilator

489.04 -> that improves blood flow. One of the other benefits of exercise is making more red blood

492.77 -> cells, but how does that happen? Tune in to the next episode in our playlist to find out how.

498.24 -> I’m Patrick Kelly, thanks for watching Seeker.

Source: https://www.youtube.com/watch?v=7-FfBidRQOE