Hypertrophic Cardiomyopathy Lesson #705

The patient was supine during auscultation.

Description

With hypertrophic cardiomyopathy, we can observe an early peaking, harsh, diamond-shaped systolic murmur. This murmur is present at the beginning of systole and stops well before S2. In diastole, a fourth heart sound gallop is present. The hyperdynamic left ventricle generates increased S1 sound intensity. S2 is single.

On the cardiac animation video, observe that the left ventricle contraction is strong and occurs in a reduced amount of time. The septal wall is significantly thicker than the rest of the ventricle, although this is not depicted in the animation.

The strong contraction of the left ventricle causes the anterior leaflet to be sucked into the ventricle, blocking the flow into the aorta and causing an aortic murmur. Concurrently, turbulent flow from the left ventricle to the left atrium causes a second murmur. Because these two murmurs occur simultaneously, you hear a single murmur.

Observe the difference between the two murmurs by shifting the stethoscope chestpiece from the aortic to the mitral valve area. First, you will hear the diamond-shaped aortic murmur and later the rectangular pansystolic murmur.