Explanation of Examination Findings

Low volume, slow-rising pulse and narrow pulse pressure

These findings result from prolonged left ventricular ejection through a narrowed aortic valve. This can be graphically presented as per Fig 1.

Graphs: normal and slow-rising pulse dynamics
Fig 1. Graphical representation of normal and slow-rising pulse dynamics. A slow–rising pulse is typical of aortic stenosis.

Left ventricular ejection through a narrowed aortic valve similary explains a heaving (also described as “sustained”) (pressure overloaded) apex beat, which is typically not displaced until late in the disease process when heart failure ensues.

 

Systolic crescendo-decrescendo murmur

The murmur of aortic stenosis is best heard over the aortic area (right second intercostal space with radiation to the carotids; see Fig 2). It should be noted that radiation to the carotids is a sensitive finding in severe aortic stenosis and should therefore be routinely sought if aortic stenosis is suspected.

Image showing cardiac ausculation areas
Fig 2. Cardiac ausculation areas

The murmur is mid- to high-pitched and starts shortly after the first heart sound and ends before the second heart sound, if this is still audible (Fig 3).

phonocardiogram output
Fig 3. Representative phonocardiogram of aortic stenosis murmur, which has a crescendo-decrescendo character, begins after S1 and ends before S2.

Because the second heart sound is predominantly generated by closure of the aortic valve, an immobile, stenotic valve typically causes a quiet or absent S2 (Fig 4).

Image of the cardiac cycle
Fig 4. The cardiac cycle. Pay particular attention to the timing of aortic valve opening and left ventricular ejection.

Remember, it is important to always assess for other murmurs if you hear aortic stenosis as mixed valve disease with a common aetiology (rheumatic fever, for example) is a common finding.