Enlarged myocardium is a disease of the heart muscle that protects the muscle from the force of its contraction. Therefore, the heart cannot pump enough blood to the organs in the body. The heart becomes weak and the four heart chambers become larger (dilated). These chambers are the atria and the ventricles of the heart. The muscles may thicken to give more force to contract to allow the blood to pump normally. Heart valves may be affected. When the chambers of the heart are enlarged This can worsen circulation. Impaired heart function can affect the lungs, liver, and other organs.