Changes in Murmurs

00:01 Squatting, we talked about this with overview changes in murmur.

00:05 With squatting rapid, you are going to increase venous return.

00:08 Most murmurs will increase, what is the big exception that you are going to predict for me? Hypertrophic obstructive cardiomyopathy, more amount of blood in your heart.

00:17 Remember.

00:18 HOCM comes under the division of the category of hypetrophic cardiomyopathy and the most common hypertrophic cardiomyopathy will be the obstructive type with what kind of hypertrophy of the interventricular septum? Asymmetrical.

00:35 Asymmetrical.

00:37 Valsalva, what happens? I have been saying this phase over and over again.

00:42 You have your closed epiglottis for which you are breathing out or expiring.

00:46 As you do so you increase your thoracic pressure.

00:48 You are going to squeeze the pulmonic capillaries and you go into phase II.

00:51 With phase II, you decrease the amount of blood returning to the left side and so, therefore, the intensity of most of the murmurs is going to decrease or are going to decrease.

01:01 Now, something that I wish to bring your attention.

01:04 Yet once again what Valsalva, tell me about MVP, mitral valve prolapse.

01:08 Four components, what are they? S1, S2. Two down, two to go.

01:13 Click and murmur, that is your pathology.

01:15 When you do valsalva, you have decreased amount of blood to the heart.

01:18 What happens to that click? That click gets closer to S1.

01:21 It is a not a delayed click, but a shortened click, isn' it? An early click.

01:27 What then happens to the murmur? It is now lengthened, right.

01:30 What happens to the intensity of the murmur? It increases at valsalva.

01:33 When we do exercise or rapid squatting and I showed you pictures before in which you would then have increased amounts of blood.

01:40 The click within get closer to S2 or it is delayed and the murmur shortened.

01:44 If you understood or if you missed that concept, go back and review.

01:47 If you have got it down, let us move on.

01:50 Let's not waste time.

01:51 Let us be efficient.

01:52 The two exceptions are exactly here.

01:54 Two exceptions are systolic murmur right, here in which with valsalva, with hypertrophic obstructive, it is going to get worse.

02:03 Mitral valve prolapse, it is going to become longer. What is the murmur? What about the click? It gets early.

02:10 Exactly what we just went through.

02:11 Let us continue.

02:12 Isometric handgrip, what is happening here? It is the fact that when you do a handgrip, you are increasing your TPR.

02:18 When you increase your TPR, then now here, who haven't talked about this.

02:22 Well, it is the first time we are seeing this, talked about handgrip, but not in reference to the following murmurs.

02:29 So murmurs of mitral regurg.

02:31 So first and foremost, clenching of fist.

02:35 You constrict your arterials, increase TPR, increase afterload.

02:39 There is more blood, where? Left in your left ventricle because of increased afterload, increased resistance.

02:43 We can all agree upon that.

02:45 Let's say that you have mitral regurg.

02:46 You tell me quickly mitral regurg difficulty with? Closing.

02:50 When do your mitral valve close? During systole.

02:53 It causes systolic murmur between S1 and S2.

02:56 What kind of murmur? All systolic.

02:57 You should be able to go through that quickly and you will.

03:01 These are steps that you have to take a medicine every single time.

03:04 The more organized your thoughts are, the faster that you can run through them, and, therefore, when an attending or an exam asks you a question, you arrive at the answer in a very efficient and quick manner.

03:15 I know it is never going to leave you. Never.

03:18 Ventricular septal defect, aortic regurgitation with all of these with a handgrip, you are going to increase intensity of the murmur because of the backup.

03:26 You can’t move forward.

03:27 Increase the afterload, increase resistance.

03:30 Handgrip versus hypetrophic cardiomyopathy, aortic stenosis.

03:34 Pay attention.

03:36 Hypertrophic cardiomyopathy, asymmetrical hypetrophy, outflow tract is very very compromised.

03:43 Thus by handgrip, you increase afterload, the seperation of the outflow tract becomes increased.

03:49 Thus, the intensity of the murmur is going to decrease.

03:52 Tell me about aortic stenosis? Normal gradient is high between left ventricle and the aorta to ensure unidirectional flow, correct? Now you do a handgrip, what happens? Less blood passing across this stenotic aortic valve.

04:07 What happens to the murmur? Decrease in intensity.

04:11 Tell me about MVP.

04:12 You have more blood left in your heart.

04:14 What happens to that click? It gets closer to S2. It is delayed.

04:18 What happens to murmur? Decreased intensity. There you have it.

04:21 That mind right there for handgrip probably one of the most important one for manuvers because students tend to get that wrong over, over and over.

04:29 You understand the pathophys.

04:30 There is no way that they are going to shake you.

04:33 You are invincible, my friend.

04:37 Increased afterload delays left ventricular emptying in HCM.

04:41 In aortic stenosis, turbulent flow reduced as well due to reduced pressure gradient.

04:47 Nice little table for you to take a look at all the different maneuvers.

04:50 I'm just going to show you one little point for each on these lines and then your own time make sure that you're clear about how to interpret this.

04:58 If you've understood everything I said, this table becomes absolutely invaluable.

05:04 Lying down, tell me about venous return.

05:06 Increased.

05:07 It's going to increase the murmur of every single murmur, except for HOCM.

05:14 And tell me about MVP, the click is delayed, the murmur is decreased.

05:18 Next, sudden standing, where is my blood? Down in legs.

05:21 So therefore, decrease venous return.

05:24 So therefore, tell me about HOCM.

05:27 The outflow tract gets worse, increase intensity.

05:30 What about MVP when there's decrease amount of blood? The click gets closer to S1, early click, long-length in murmur.

05:36 Let's move on.

05:37 Squatting, increased venous return.

05:39 Do you see the point now? You take a look at squatting, you're lying down.

05:44 Pretty similar.

05:46 Valsalva.

05:47 Take a look at valsalva in standing up, pretty similar, huh? Post PVC beat.

05:55 So this is a little bit more detail in terms of your premature ventricular type of issue.

06:00 Hand grip.

06:01 With hand grip, you're going to increase afterload.

06:03 There is more blood that's going to be left inside my heart.

06:07 Now, be careful here.

06:09 What stenosis of aortic and pulmonic with hand grip, it's about the pressure gradient.

06:14 Therefore, the intensity murmur is going to decrease.

06:16 In HOCM, hand grip, more blood in my heart.

06:19 So therefore, more separation of the outflow tract.

06:22 MR, MS and AR in those cases, you are then going to increase intensity murmur, especially MR and AR.

06:31 Amyl nitrite, now where is my blood? With amyl nitrate, what ends up happening is that you have decreased preload because you have decreased venous return.

06:39 Think of nitrate as causing decreased preload due to vein no dilation.

06:44 So therefore, there's more pooling of your blood in your veins, not your heart, the veins.

06:50 So you have more blood in your veins less than your heart.

06:53 What then happens to hypertrophic obstructive cardiomyopathy, the obstruction? Well, it gets worsen, increase intensity.

07:01 Clear.

07:03 So these are things that you're paying attention to, as you're going through the various maneuvers.

07:07 You want to try to get a good idea of at least some of the ones that I just mentioned here, for sure.

07:12 And then anything beyond that, well, you take a look at on your own time.

07:15 And you do this every so often, you do this to reinforcement.

07:18 And before you know it, this stuff is coming to you like it's instinct.

07:23 Trust me.