An enlarged ventricle is usually due to either cardiomyopathy (a weakening of the heart muscle) or valvular heart disease. Valve disease is usually treated by correcting the underlying valve problem (initially with medicines, often later with surgery). The most common cause of an enlarged ventricle is cardiomyopathy,a serious disease in which the heart muscle becomes inflamed and doesn't work as well as it should. Initial treatment is with medications, such as diuretics, digitalis, vasodilators (ACE inhibitors and/or ARB inhibitors), and beta blockers, such as carvedilol (Coreg) or metoprolol (Lopressor, Toprol XL). In more severe cases special pacemakers or defibrillators are used. Only in the most difficult cases are heart transplants occasionally required. Hope this helped you out. Good luck!