Hypertrophic Cardiomyopathy: Pathophysiology (Nursing)

00:01 Hi, I'm Professor Lawes and welcome to this portion of our video series, where we're going to talk about hypertrophic cardiomyopathy.

00:09 Now, we're going to start with a picture of a heart.

00:11 And then I'll give you a tip on how to remember what this word means. So, let's start with the heart.

00:17 Now, this is what a normal heart would look like.

00:20 You can see we've cut around the sacs, so you can see into the inside.

00:23 Now, by the magic of virtual reality, well close to it, we're going to cut through the heart, so we can look specifically at the left side of the heart.

00:34 Remember, the right side receives the blood from the body, the left side, it leaves the heart and goes out to the rest of the body.

00:42 So, if we're going to look at the left side, that's the one that's responsible for the heavy lifting, or the pumping out to the whole side.

00:49 So you saw our scalpel, just slide down there.

00:53 Now, we're going to show you that same view and a cleaner drawing.

00:57 Here, you see just the left side of the heart.

01:00 Now, this is a normal heart. You can see of the aorta, the left atrium, the left ventricle, this is a pretty good representation of what a normal heart would look like.

01:10 Now, notice those black bars in the left ventricle.

01:14 They're kind of giving you an idea of how thick the wall of the ventricle is.

01:19 Look, what happens in hypertrophic cardiomyopathy.

01:25 Wow, that's a really significant difference.

01:29 So, HCM is hypertrophic cardiomyopathy.

01:33 I always like to break that down to help you use this in other videos, and while you're studying for your exams, you can recognize these words.

01:41 "Hyper-" means excessive. "-Trophic" is growth.

01:45 "Cardio" means heart, "Myo" means muscle, and "-pathy" -- bad news.

01:53 So this is affecting a cardiac muscle, in a bad way.

02:00 And because it's excessively growing, thickened wall.

02:05 The reason this happens is because the heart has been overloaded, but the heart is meant to be able to contract and release.

02:15 This is no longer going to be an efficient heart, or even maybe even an adequate heart with a wall that is this thick.

02:24 Let's talk about some context or the epidemiology of cardiomyopathy.

02:28 First of all, it's abbreviated CMP.

02:33 Now, that might be a little confusing to you, but that stands for cardiomyopathy.

02:37 There's a descriptor word that goes in front of that.

02:40 What we're talking about here is hypertrophic cardiomyopathy, but there's also dilated cardiomyopathy.

02:48 Now, dilated cardiomyopathy is the most common cause.

02:52 This one hypertrophic cardiomyopathy is less common than the dilated CMP.

02:58 It also affects men more than women, just like in the dilated.

03:04 But here's some places where it gets different.

03:06 This is most commonly an inherited cardiomyopathy, Unlike dilated, hypertrophic cardiomyopathy is most commonly caused by an inherited condition.

03:18 The sad thing is, this is a well known tragic and traumatic cause of sudden death in athletes.

03:27 That's why those physicals that are done on athletes before they're cleared to play are critically important that the heart zones are listened to in a very quiet environment by a skilled clinicians.

03:39 So they can catch signs of this and deal with it before the athlete is at risk.

03:45 Here are some causes of hypertrophic cardiomyopathy.

03:50 Hypertension, that's one because you're increasing that workload of the heart.

03:55 And sometimes, you can end up with these hypertrophic impacts on the wall.

03:59 Next, is aortic stenosis.

04:01 Now, aortic stenosis means that valve is going to be stiff, which would clearly increase the workload of the heart.

04:09 It's having to push harder against that stiff valve.

04:12 Kind of the same effect as hypertension, but just in a very specific location.

04:18 Now, lastly, there's also a genetic component.

04:20 Now, that gets pretty complicated and I would not memorize that if I were you.

04:25 But we just wanted you to think about "Hey, here are some major causes of hypertrophic cardiomyopathy." High blood pressure, a really stiff aortic valve, and genetic causes.