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Health and medicine
Course: Health and medicine > Unit 3
Lesson 5: Hypertension- What is hypertension?
- Intro to hypertension (Pressure, flow, and resistance)
- Intro to hypertension (systolic and diastolic blood pressure)
- Stages of hypertension
- Hypertension types and causes
- Primary hypertension
- Secondary hypertension
- Hypertension effects on the blood vessels
- Hypertension and blood vessel damage
- Hypertension effects on the heart
- Hypertension and heart damage
- Complications of hypertension
- Hypertensive crisis
- Diagnosis of hypertension
- Treatment of hypertension
- 4 lifestyle changes to help manage hypertension
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Complications of hypertension
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Want to join the conversation?
- Can't the heart just suck up its own blood instead of needing coronary arteries?
Also, are there any coronary veins?(3 votes)- The heart muscle is not in direct contact with the blood in the heart as it is covered by the endocardium, hence the need for coronary arteries. Yes, there are coronary veins. They drain into the right atrium.(4 votes)
Video transcript
- [Voiceover] So, once
you have hypertension or high blood pressure,
there are a lot of potential complications that can start
to crop up as a result, many of which you might
not necessarily think of or associate with
hypertension, but they can and definitely do happen. And we can sort of split
these complications up into three categories, the first of which is those that involve
the head and the brain. Specifically, a major complication is hypertensive retinopathy. What is that? Well, the first part of
retinopathy means retina, and then "pathy" is disease, so this
is a disease of the retina. And your retina is this
critical component of your eyes. You wouldn't be able to
see the world as you do without it. It's the innermost layer of
your eye, and it takes in light and then helps transmit
that light as an image to your brain. It's sort of like if your eye was a camera and then your retina would be the film. And depending on which part
of the retina the light hits, it'll send that information
to your brain through these nerve fibers for
development into an image. Now, this piece of film,
like anywhere in the body, needs oxygen, right? And where does it get that oxygen from? Well, your blood vessels. But if those blood vessels are damaged due to hypertension, you can
start having vision problems. And eye doctors or
ophthalmologists can take pictures of your eyes and actually see the damage to the tiny arteries in your
eyes due to hypertension. This is a pretty typical
image of your retina. And if hypertensive
retinopathy is present, you'll often be able to
see this leakage of blood in these pictures due to
weakened blood vessels. Now, the other major
complication that can come about from hypertension that might
be a little more familiar is stroke. And since your brain is an
organ, arguably one of the most important organs you have, it
obviously needs a very solid and dependable supply of
blood at all times, right? Well, if the arteries
that supply a certain part of your brain with oxygen get clogged, or if they burst even from being too weak, your brain might not receive enough blood. And within minutes, those
oxygen-starved brain cells can start to die off, and
whatever function that part of the brain has might be lost. All right. So, the next major category
is complications to the heart. Specifically, hypertension can
be a major, major contributor to heart failure, where the
heart doesn't pump as well as it once did. And what can happen with
heart failure is that you get left ventricular hypertrophy,
which is muscle growth of your left ventricle. Since there's more resistance
in your blood vessels, your heart now has to work
harder to pump blood, right, especially the left ventricle,
since it sends blood to your body and your organs. Similarly to how your biceps
bulk up from lifting weights, your left ventricle gets
bigger from pumping harder. Unfortunately, though,
hypertrophy of the left ventricle isn't a healthy adaptation
to an increased workload. And this change in shape
of the left ventricle actually causes a decrease
in pumping ability, and that's when the heart begins to fail. Now, another major effect to the heart is coronary artery disease. In the same way that
other organs need blood to survive, your heart needs
its own supply of blood to survive, too. So, the coronary arteries
supply the myocardium or the heart muscle with blood. And these can become narrowed or weakened from hypertension and form these clots that sort of block off the blood supply to the heart's muscles. And without a blood supply,
those cells can start to die off, which can cause what's known as a heart attack, also known
as a myocardial infarction. Now, the final category is
peripheral artery disease, which we sometimes abbreviate PAD, and this is an atherosclerosis
or a buildup of plaque in the body outside the
vessels of the heart, the head, and the brain, kind of a catchall category
for things not in the last two, which is why we call
them peripheral arteries. Now, some of the most
commonly affected areas are the blood vessels that
carry oxygen to your legs, your arms, your stomach, or your kidneys. Decreased oxygen supply
due to weakened or blocked arteries from hypertension
to really any part of the peripheral organs
or tissues can cause things like ulcers, gangrene, and loss of tissue in the affected area. The kidney specifically, though,
deserves special attention because they tend to be a
very common organ that can be damaged by hypertension. If plaque builds up or
the arteries weaken, and you get a reduced
blood flow to the kidneys, then they can become
damaged and their functIon can be reduced, just like any other organ. But what's their function? Well, the kidneys help
you regulate fluid volume in your body, right, like at any time they decide
if you need more or less blood. So, if their arteries get
blocked, they'll see this reduced blood flow and be like,
"Hey, we must be dehydrated "or something because
there's way less fluid." And then, they'll release
some hormones that cause the body to hold on to more
fluid, which has the effect of increasing your flow,
and therefore increasing your blood pressure. Also, with less oxygen
reaching the kidney cells, just like any other organs
and tissues, they can be injured and even start to
die off, which makes it even harder for them to do their
job of balancing fluids.