 Here everybody, Dr. O, in this video we're going to talk about auscultating or listening to the heart and we're going to talk about heart sounds. So your two normal heart sounds, maybe you've heard people and like I said, your lub-dub, I always say lub-dub, but your two normal heart sounds are what are called S1 which is lub and S2 which is dub or dub. So S1 is the sound created when your two AV valves close and S2 is the sound when your two semi-lunar valves close. So lub-dub, let me show you a picture, kind of a little fun with it here. So this would be the lub, as the two H over in tricular valves, your bicuspid and bicuspid valve slam shut. That would be the lub, this here would be the dub as the two semi-lunar valves close. So your heart sounds would be lub-dub, lub-dub, lub-dub, alright so those are your two normal heart sounds, S1 and S2. There are a couple more, S3 can be normal, but it's rarely heard in healthy individuals, we don't know what it is, maybe it's just a blood flow thing, but you can hear S3 occasionally. And then S4, if you hear S4, that's generally a problem, if someone has a real stiff ventricles or the ventricles are real large or there's something wrong with the heart, you might hear a sound called S4. So don't worry about S3 and S4, S1 and S2 would be the normal heart sounds, but if you want to know when you would hear S4, it would actually be before S1, so it's not on this list, but it would be S4, then S1, then S2, then S3. Alright, as far as listening to the heart, so the key thing to note here is you listen in the best place to hear, not where the valves are, so you can see the four valves there in the center of the heart, then the locations where you actually listen are different, and that's because there's bone over the heart, so you want to find the best place to listen. Okay, so your pulmonary and aortic valves, you listen in the second intercostal spaces right below the second rib, so on the left side for the pulmonary semilunar valve, on the right side for the aortic valve, then I travel down to the lower sternal border. I like to listen on both sides to listen for the tricuspid valve, or the tricuspid valve, sorry, and then the mitral valve or the bicuspid valve, you go to the fifth intercostal space near the mid-clavicular line, so I'm not asking you to know those, we just note that the places where you listen to for the heart sounds is not right over the valves, it's just the locations where it's the best place to hear them. Another thing you might do if you're listening to someone's heart is have them breathe or hold their breath, these kind of things. When you inhale, when you have a patient inhale, if they have a murmur or an abnormal heart sound on the right side of their heart, inhaling may make it louder and easier to hear. Exhaling may help hear a murmur on the left side of the heart, so having someone breathe in and breathe out actually has multiple purposes. I occasionally have people hold their breath as well. So, okay, sorry, so those are the heart sounds and what the sounds are and where to listen to them or auscultate the heart to hear them. I hope this helps. Have a wonderful day. Be blessed.