And what did we learn from listening to the murmurs at the upper left sternal edge? Let's listen together focusing on those murmurs using again the diaphragm of the stethoscope and using the carotid vessel as a timing device. Everyone listen together. [Cut-away] We heard two murmurs at the upper left sternal edge, one in systole with the carotid impulse and one in diastole. The diastolic murmur was the most prominent. It was decrescendo and high frequency. That type of diastolic murmur [sounds] could be due to aortic regurgitation or pulmonary regurgitation. We also heard a systolic murmur. The systolic murmur was short, it was in early systole and such murmurs coming out of the outflow tract are due to flow alone, not significant stenosis of a valve. Now, in the context of our patient, a notable observation was when the patient breathed in the murmurs got louder. So, it was [sounds]. That says these are right sided events. As you breathe in you augment right heart filling, enhancing the intensity of these murmurs. So, in our patient, the murmurs are due likely to pulmonary regurgitation with a brief, early, short flow murmur back across the pulmonary valve.
Osciloscopic image
By viewing an oscilloscopic image and simultaneously listening, we can further appreciate these auscultatory events.
Inspiratory increase
An inspiratory increase in the intensity of auscultatory events indicates their right heart origin, as inspiration decreases intrathoracic pressure increasing venous return.
Murmur discussion
Let us review the murmurs at the upper left sternal edge. The systolic murmur is short, early peaking and crescendo-decrescendo. This murmur is functional and likely due to increased flow across the non-stenotic pulmonic valve.
Pressure curves
The diastolic murmur is decrescendo and also referred to as the Graham-Steel murmur. This murmur is also functional and not due to organic disease of the pulmonic valve, but rather other hemodynamic events, as demonstrated by the simultaneous pulmonary artery and right ventricular pressure curves. The pulmonic valve is incompetent due to pulmonary artery dilatation. High diastolic pulmonary artery pressure is exerted on this valve throughout diastole and accounts for the murmur's early onset, high frequency, decrescendo configuration and long length. In contrast, patients with congenital pulmonary regurgitation have lower pulmonary artery pressures and the diastolic murmur is low frequency. [Sounds]