The human heart is divided into four chambers. One of the four chambers, the left ventricle, is the chamber mainly responsible for pumping blood out of the heart into the circulation. Hypertrophic cardiomyopathy is a genetically inherited disease causing an abnormal thickening of heart muscle, especially the muscle making up the left ventricle. When the left ventricle becomes abnormally large, it is called left ventricular hypertrophy (LVH).