Hypertrophic cardiomyopathy physical examination

Overview
There are numerous teachers on physical examination that allow one to distinguish hypertrophic cardiomyopathy from other conditions such as aortic stenosis.

Cardiac examination
On physical examination, (as shown in the table below) maneuvers that decrease left ventricular filling augment the murmur and maneuvers that increase afterload or filling decrease the murmur. The murmur is characteristically a crescendo-decrescendo systolic murmur. There may be paradoxically split S2, and S3 or S4 as well as mitral regurgitation. Hypertrophic cardiomyopathy(HCM) can be differentiated from AS by the fact that the murmur of AS does not change substantially with maneuvers. The character of the pulse in AS is parvus et tardus, while a bisferiens pulse is noted in HCM. S2 is louder in HCM than AS.

The physical findings of HCM are associated with the dynamic outflow obstruction that is often present with this disease.

Upon auscultation, the cardiac murmur will sound similar to the murmur of aortic stenosis. However, this murmur will increase in intensity with any maneuver that decreases the volume of blood in the left ventricle (such as standing or the strain phase of a Valsalva maneuver).

If dynamic outflow obstruction exists, physical examination findings that can be elicited include the pulsus bisferiens and the double apical impulse with each ventricular contraction. These findings, when present, can help differentiate HCM from aortic stenosis. In addition, if the individual has premature ventricular contractions (PVCs), the change in the carotid pulse intensity in the beat after the PVC can help differentiate HCM from aortic stenosis. In individuals with HCM, the pulse pressure will decrease in the beat after the PVC, while in aortic stenosis, the pulse pressure will increase.