Next, we shall carry out auscultation in our patient and we shall begin together by listening at the upper left sternal edge. Now, of course, you always listen in all the classic acoustic areas in your patient, and I have already listened at the upper right and I heard a murmur. I also heard a murmur at the upper left, where we are going to listen. But I don't want you to pay attention to that murmur at this time, let's focus on the heart sounds, and let's relate those heart sounds to respiration. I'm going to listen with you at the upper left sternal edge. I'm going to place a cotton swab on the carotid so you can time systole, and we're going to watch respiration and listen carefully to the heart sounds upper left sternal edge. [Cut-away]
Choose the best description of the second sound at the upper left sternal edge in our patient: