Dilated Cardiomyopathy: Pathophysiology (Nursing)

00:00 Hi, welcome to our video series on Cardiomyopathy.

00:05 Now, in this portion of it, we're going to talk about the most common form, which is called dilated cardiomyopathy.

00:11 Now, you'll see on the screen what looks like to be a healthy heart.

00:15 Just to kind of help you review where we are to kind of cut the outside sac out.

00:20 So, you can see, where the right atrium, the right ventricle, the left ventricle, and the left atrium.

00:26 Now, the heart sometimes we picture standing straight up, but she was kind of slanted a little bit in your chest.

00:32 Keep in mind when you're assessing heart tones, where each of these chambers are, and will also help you locate where the valves are.

00:40 So let's break this down. What is dilated cardiomyopathy? Well, we put this picture in here to show you. See that blue line? That's right. We're going to... figure.

00:52 Pretend that we saw that heart right in half.

00:56 I wanted you to have the perspective, and our artists wanted you to have the perspective of what we're talking about throughout the rest of this series.

01:03 So, we're going to slice right down.

01:06 You'll see the scalpel come on the screen? Slice that heart open.

01:09 And here's where we're going to start talking about dilated cardiomyopathy.

01:14 So here we are, this is our section right here.

01:18 You can see that you have the aorta, you see the left ventricle, the left atrium, and the mitral valve in between. This is a normal heart.

01:27 But I don't want to go too fast.

01:28 I want to make sure you're picturing.

01:30 Oh, yeah, that was the scalpel slicer right down the middle of the heart.

01:34 And now we're looking at the left side of the heart.

01:37 The reason we do that is because the left side of your heart is responsible for pumping blood throughout your whole body.

01:45 If that left ventricle is struggling, and it's not able to pump blood out to the rest of the body efficiently, you're going to end up in heart failure.

01:54 Now, we talked about there's different kinds of heart failure or cardiomyopathy, this one is called dilated.

02:01 And that's because something has happened, where that left ventricle has had to work harder, and get bigger.

02:08 And then after a while, that helps in it compensates, but you go long enough, and the heart is going to become enlarged and not strong. It's going to be significantly weakened.

02:19 That's why it's called dilated cardiomyopathy.

02:23 So, look at this, see the difference? Think back to what the normal heart look like.

02:29 And here is what the dilated heart. What's different.

02:34 Wow, the chambers are significantly different.

02:37 Do you see how they're dilated or bigger? That's where the name comes from for dilated cardiomyopathy.

02:44 Why did this happen? The heart was overworked in some way.

02:47 Now, we'll talk about the things that caused the heart to be overwork that can lead to this. But remember, this is progressive.

02:53 It happens over a period of time. So it doesn't happen overnight.

02:58 But it happens over a period of time the heart becomes enlarged, it these dilated chambers, it becomes weakened and unable to pump blood efficiently.

03:07 So, let's start off right at the beginning with epistemology is.

03:11 The most common type of cardiomyopathy is? Yeah, you should know that one now.

03:16 It's dilated cardiomyopathy.

03:18 Now, it affects men more than women.

03:21 So, that's just the statistics, we kind of like you to be aware of, Why don't we take the time to do that? Because we want you to be on the lookout for these type of cues.

03:31 If you're with a client, and they're a male client, you know, this could be a very common cause or something going on, if you see the other side.

03:39 Now, it's usually diagnosed between 20 and 50 years of age.

03:43 Okay, that's a pretty wide calf, right? 20 to 50 years of age.

03:49 Think about 20, that's a young person.

03:51 They had something very significant happened in their body for them to develop this that young.

03:56 Age 50, has had three more decades to develop their cardiomyopathy, and that was a much slower progression of the disease.

04:05 Here's the sad part.

04:06 50% of the patients will die within two years of being diagnosed and only 1/4 or 25% of them survive longer than five years.

04:17 Okay, let that sink in. That's a pretty scary statistic.

04:23 That when the heart can no longer pump effectively, it affects obviously the entire rest of the body.

04:29 So, that's a really, really high mortality rate.

04:33 So, our job is to help patients minimize their risk of developing this.

04:38 That's what our role is to recognize early signs, to give them tools and strategies to intervene, and hopefully prevent them ending up in this state.

04:47 Now, there are some causes that are idiopathic, and that's just a really long word.

04:51 This is we're not exactly sure why this may have developed.

04:55 But there's other causes that we are aware of.

04:59 First one, Viral.

05:00 Now, I've listed some of the possible viruses there.

05:03 You see those, these can sometimes cause this effect on the heart, and you end up having cardiomyopathy.

05:09 But there's several more.

05:11 Now, this one is going to make a lot more sense to you. Hypertension.

05:15 Think that through. We talked about the left ventricle being the one that pushes blood out to the rest of the body.

05:21 If the person has really high blood pressure, does the heart have to work harder? Absolutely, because it's really having to push against that blood pressure to get the blood out to the rest of the body.

05:34 That will cause those changes we talked about.

05:36 The left ventricle first compensate and get bigger, but then it gets overused. Becomes kind of big and floppy and mushy.

05:44 And it can no longer push blood efficiently out to the rest of the body.

05:48 Now, another one you might not have thought of is pregnancy.

05:51 But pregnancy, I mean, growing a human does put an extra workload on the body, for sure.

05:58 And some women develop cardiomyopathy, after pregnancy.

06:02 Now, coronary artery disease kind of links back up to hypertension, right? One of the reasons you have hypertension is that you have coronary artery disease that has a cluded those arteries, which is going to elevate your blood pressure because it takes more force to move blood through a vessel that is smaller than one that would be wide open.

06:23 So, pause here. That's already five causes of cardiomyopathy.

06:30 Can you close your eyes and try to name them? Can we re-said idiopathic? We don't know.

06:36 What was the other one? Viruses, hypertension, pregnancy, and coronary artery disease.

06:44 Now, we have more, but I want you to stop and think how am I going to remember these together? Let's take a look at the sixth one.

06:50 I'm going to loop them into a category, right? Group them all together.

06:54 Immune-mediated myocarditis.

06:57 So here's three possible causes of an immune-mediated, meaning caused by the immune system.

07:02 inflammation of the heart that causes this damage.

07:05 First one, systemic lupus erythematosus.

07:09 You'll heard that referred to as lupus, sarcoidosis, or vasculitides.

07:14 These three can lead to damage to the heart that ends up in cardiac myopathy.

07:19 Remember, how you put these together, they're immune mediated.

07:24 Now, that's not all. We've got other possible causes.

07:27 There can be toxins. So, when you group the toxin together, think of things like extreme alcohol abuse can cause cardiomyopathy.

07:35 Cocaine use. Cocaine is really hard on your heart, and other illicit drugs. Too many to list here.

07:43 But any drug that causes your heart to work harder, could end up causing cardiomyopathy.

07:50 We've got other drugs too.

07:51 Now, the ones we were talking about before, were street drugs, illicit drug use.

07:55 This is talking about drugs that you're taking to try to treat something with a prescription.

08:00 Particularly things like chemotherapy.

08:03 Now, I had a friend who had breast cancer, and the chemotherapy that she took for the breast cancer, she ended up dying of heart failure.

08:12 Her chemotherapy cured her of the cancer, but it was so toxic to her heart, she ended up dying from congestive heart failure.

08:19 So, chemotherapy is good, but also can be a high risk drug in some cases.

08:25 Also antiretrovirals, hydrochloroquine all these types of medications have been known to cause this.

08:31 So, do we know who's going to develop this cardiomyopathy? We don't really know for sure.

08:39 But we do know that there's a history and a pattern of these things that we're talking about, of putting a patient at increased risk to develop cardiomyopathy.