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.