Diagnosis and Echocardiography in HCM

Hypertrophic cardiomyopathy is cardiology's great masquerader. Sometimes, it simulates coronary artery disease when patients have chest pains or abnormal electrocardiograms. Sometimes, it resembles valvular heart disease with heart murmurs. Sometimes, it resembles dilated cardiomyopathy with heart failure. Sometimes, it has no symptoms at all and resembles normal.  Often, HCM diagnosis is delayed when symptoms are attributed to asthma, anxiety, panic attacks, mitral prolapse or other cardiac conditions. With care, the diagnosis of HCM can be made by echocardiography.


In rare cases adolescents and young adults with no prior symptoms at all can die suddenly without knowing that they have the disease. HCM is the most common cause of sudden cardiac death in young athletes and in people under 30 years of age. Ventricular fibrillation, a chaotic heart rhythm, is the cause of death.


Proper therapy depends on accurate diagnosis of HCM. We make the initial diagnosis with an echocardiogram. Echocardiography is a non-invasive, non-Xray imaging technique that uses sound waves to picture the heart.


An echo machine

HCM is marked by thickening of the heart that occurs in the absence of significant high blood pressure or heart valve disease. Normally, heart walls are 11 mm or less in thickness. Patients with HCM have a characteristic thickening of the heart walls that can range from 14 to 60 mm, visible though echocardiography. By bouncing ultrasound off the heart, an image is produced which is recorded digitally for analysis. Below are examples of cross-sectional images of a normal patient and patients with HCM.


Normal Patient

Healthy Patient One Healthy Patient Two
HCM Patient One HCM Patient Two

HCM Patient

Particular thickening of one part of the heart, the interventricular septum, is characteristic of patients with HCM. In the cases above, the thick interventricular septum is marked with a *.