Dr. Usman's Cardiology Notes

  Today inshaAllah we will be talking about an interesting topic in cardiology, we will discuss heart sounds! Without further delay, let’s get into it! Heart sounds happen as a result of valve closure, namely atrioventricular valve: mitral and tricuspid and this gives us S1 sound and we have S2, which happens when aortic and pulmonic valve close. So normally we would have something like this: This is s1 and this is s2 the area between s1 and s1 is systole. in other words, when the AV valves are closed and the pulmonic and aortic valve are open, it is systole, where the blood is being pumped out of the ventricles. Now that we have this basic understanding, we are good to proceed. Abnormal heart sounds can be either of an added sound: S3, S4 for example, or can happen in the form of murmurs sometimes Murmurs can be either systolic or diastolic, whether they happen in systole or diastole So now we will focus on visualizing added sounds and murmurs ...

In this video we are going to discuss four major points by which you can differentiate opening snap (OS) sound of mitral stenosis (MS) from third heart sound (S3) clinically. And the examples of these two sounds. 1. First major difference is that opening snap is associated with loud first heart sound (S1). 2. Secondly opening snap is short sharp click best heard at left lower sternal border with diaphragm of the stethoscope, whereas third heart sound is best heard at apex with the bell of stethoscope. 3. Third difference is that on standing opening snap moves further away from A2, whereas S3 doesn't change its position on dynamic auscultation. 4. And the last difference is measuring the distance of S2 from opening snap with phonocardiography, as its difficult to appreciate clinically. S2 to opening snap distance is usually less than 100 msec whereas the distance of S3 from S2 is more than 100 msec. These are the major differences between these two sounds. Example sound of opening ...