What's that Sound?

What can you expect to hear in patients with valve disorders?

First, a short description of each valvular disorder:

• Aortic Stenosis: the aortic valve orifice narrows and obstructs the left ventricular outflow during systole. Increased resistance to ejection or afterload result in ventricular hypertrophy.

• Aortic Regurgitation: the aortic valve leaflets do not close properly during systole leading to leakage (or regurgitation) back into to left ventricle.

• Mitral Stenosis: valve leaflets fuse and stiffen while the chordae tindineae (the white string looking parts in the picture below) contract and shorten.

• Mitral Regurgitation: the mitral valve is prevented from closing completely during systole, allowing back-flow into the left atrium.

• Mitral Valve Prolapse: leaflets enlarge and prolapse (slip out of place) into the left atrium during systole. Usually benign, but in some cases may progress to mitral regurgitation.

Need a visual?

Notice that the valves in the image above are rather close together. This might lead you to believe they would be hard to distinguish from each other - however, auscultation of the aortic valve and mitral valve are in two VERY different places.

As you can see in the picture above, the Mitral area or apex of the heart is found on the left at the 5th intercostal space along the midclavicular line. If you've a patient with larger breasts, you may have to put on gloves and move it to the side to hear properly.

The Aortic area is to the right of the chest at the 2nd intercostal space near the sternum. Notice that the area nearly lines up vertically with the bony prominences on the clavicle. 

Always pay attention to landmarks when auscultating!

The next thing to ask is what do these valvular disorders sound like?

 Let's listen to a normal heart sound for the sake of better comparison. This link will open a youtube video for easier listening. Make sure to read the notes on the video.

Normal Heart Sounds 

Note that the sounds in the video mimic what can be heard at the mitral area.

Easy enough, right?

Moving on, here's what a case of mild aortic regurgitation can sound like. Once again, make sure to read the notes on the video - they can be really helpful in explaining what and why it sounds like that.

Mild Aortic Regurgitation

 Remember: Regurgitation is the back-flow of blood! Blood is a fluid! So listen for the sound of flowing fluid - One cardiologist described it to me as "water swishing in a washing machine".

And where do you go to hear this?

Second right intercoastal space next to the sternum!

This is Aortic Stenosis. It can be heard in a diamond shape at the aortic area and comes across as a harsh crescendo-decrescendo during systole. Different source, so there's no notes to read with this one; but do pay attention to what the narrator says in the video as it can be very helpful.

Aortic Stenosis

Notice that the murmur is at the end of the lub part of lub dub.

Mitral Stenosis is a rumbling, apical diastolic murmur. Apical meaning, of course, at the apex of the heart, also known as the mitral area at the 5th intercoastal space! The video quality on this one is a little rougher than previous. Listen closely - there are three different examples. They will sound very similar to the Aortic Stenosis, but the murmur is on the dub of lub dub.

Mitral Stenosis

Mitral Regurgitation is a high-pitched systolic murmur at the apex of the heart that can sometimes radiate to the left axilla. Severe regurge results in S3. Once again, the video quality is a little rough. The Mitral Regurgitation sounds very similar to Aortic Regurgitation at first.

Mitral Regurgitation

Notice that the murmur is on the lub part of lub dub. Remember that regurgitation is back-flow of blood and will sound similar to water swishing!

Last but not least, we have the Mitral Valve Prolapse. What you should hear is a midsystolic click - it's very obvious in the video. Mitral prolapse may also have a late systolic murmur that can be heard at the apex of the heart.

Mitral Valve Prolapse

How do you remember whether the murmur can be heard in diastole or systole?

Well, luckily acronyms are to the rescue once again. This is how I remember:

Diastole  =  "Dammit, Always Read Maps Straight"

(Aortic Regurgitation, Mitral Stenosis)

Systole  =  "Secret: Artie Says Men Read More Porn"

(Aortic Stenosis, Mitral Regurgitation, Mitral Prolapse)

Are they the most clever or elegant of devices? No, not at all. 

Should you say either of these out loud during a test? I wouldn't recommend it. 

But, if they help you remember then they've done their jobs. Don't like these? Think up your own! It's always easier to remember something if you have to think of it yourself. Only you truly understand your brain and what will help you remember.