Hi, Definitely, one of the main cause of HCM is genetic thru mutation in genes, so that it is inherited thru autosomal dominant transmission. Of course, the symptoms of HCM can develop at any age, but primarily it is due to hypertrophy of heart muscles reducing the availability of space for blood, thus pumping the less amount of blood out of heart and producing symptoms. Mostly, the hypertrophy of interventricular septum or left ventricle is there. Your cardiologist might have made his diagnosis on the basis of some observations. Usually non-invasive tests like echocardiography or cardiac MRI are able to diagnose the thickening of heart muscles for a diagnosis of HCM. However, in a few cases, cardiac catheterization may be indicated, to ascertain the pressure difference between left ventricle and ascending aorta, if any. This can determine the degree of stenosis of aortic valve and hence likelihood of severity of symptoms. Still, everything is to be done under guidance of your cardiologist. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Satnarain Bansal, General & Family Physician