Definition:

Also known as idiopathic hypertrophic subaortic stenosis (IHSS) or asymmetric septal hypertrophy, hypertrophic obstructive cardiomyopathy (HOCM) is a disorder in which the wall separating the left ventricle and right ventricle (interventricular septum) has hypertrophied (gotten excessively thick) causing a decreased size in the ventricles with disturbance in the blood flow from these chambers.  They are usually inherited from the family, but there have been cases where it has happened sporadically.  

Symptoms:

• Angina - chest pain that occurs at rest
• Syncope - fainting spells after exercises
• Arrhythmias - abnormal heart rhythms
• Dyspnea on exertion
• Orthopnea (shortness of breath while lying flat)
• Paroxysmal nocturnal dyspnea (waking up at night because of shortness of breath)

Diagnosis:

• Physical exam
  • Heart murmur - systolic ejection murmur along left sternum heard with stethoscope which increases in intensity with Valsalva and diminishes with squatting
  • Carotid upstroke
• EKG - left ventricle hypertrophy, left atrial enlargement, and ST/T-wave changes
• Echocardiography - increased septal thickness, aortic valve fluttering
• Cardiac Catheterization - assess coronary anatomy and degree of obstruction

Treatment:

• Medications
  • Beta-blockers
  • Calcium channel blockers
• Surgery
  • Myomectomy - reducing left ventricle septum thickness
  • Mitral Valve Replacement - helps relieve obstruction
  • Pacemaker implantation - reduces bloodflow obstruction
• Antiarrhythmic therapy with implantable defibrillator - since most patients die suddenly