Now, let us listen at the upper left sternal edge in our patient. We will use the cotton swab over the carotid vessel impulse to indicate systole and also watch respiration. Everyone listen. [Sounds]
Discussion of findings
Our patient has a short, mid systolic murmur, that is, a murmur that begins just after S1. It peaks early and has a crescendo-decrescendo shape. The second heart sound demonstrates normal respiration variation. With inspiration, P2 is delayed .06 seconds after A2. In expiration, P2 moves back so that the two sounds are merged as one. Normal intensity of P2 suggests normsl right ventricular pressure.
Murmur
By viewing a graphic image and simultaneously listening, we can further appreciate these auscultatory events. [Sounds]
The murmur at the upper left sternal edge is mid systolic, short, early peaking, crescendo-decrescendo and mid frequency. Murmurs at the upper left sternal edge that peak in early to mid systole, typically result from turbulent blood flow when the majority of blood is ejected from the right ventricle.
Differential diagnosis
The differential diagnosis of the murmur heard at the upper left sternal edge in our patient includes an innocent pulmonary flow murmur, the murmur from increased pulmonary blood flow due to an intracardiac left-to-right shunt that augments normal systolic blood flow into the pulmonary arteries and the obstruction murmur of mild pulmonary valve stenosis. Interpretation of the murmur depends upon the findings on the remainder of the cardiovascular examination, in other words, the company that the murmur keeps.