According to the American Heart Association, an enlarged heart is characterized by an increase in the size of the heart that may be caused by an increase in the thickness of the heart muscle. This condition, also called cardiomegaly, is typically a symptom of another condition, such as coronary artery disease or high blood pressure. If you have an enlarged heart, you may be at risk of developing additional medical complications.
Heart Failure
Enlargement of the heart may interfere with the ability of the heart to pump adequate levels of blood throughout the body. The heart muscle may become stressed because it can't meet the demands of the body. This may cause the heart muscle to weaken and may prevent the heart from being able to pump blood through the body in an efficient manner, leading to heart failure.
Heart Murmur
The Mayo Clinic says that if you have an enlarged heart, two valves within your heart--the mitral and tricuspid valves--may not function properly. An enlarged heart may cause these valves to become dilated, preventing the valves from closing properly when the heart beats. If the valves don't close properly, blood may be able to flow backwards through the heart. The backflow of blood creates a specific sound called a heart murmur that can be detected by your cardiologist (heart doctor). Though a heart murmur may not produce any additional symptoms, this condition should be monitored by your cardiologist.
Blood Clots
Enlargement of the heart may increase your risk of developing blood clots within the heart. When the heart pumps normally, these blood clots can detach from the heart and flow through the circulatory system. If this occurs, blood clots can sometimes become stuck within the blood vessels and prevent the normal flow of blood. If blood circulation is cut off from vital organs, such as the brain or heart, you may experience a stroke or heart attack. Clots that develop on the right side of your heart can detach and flow through the blood into your lungs. If the blood clot blocks blood flow to your lungs, you may be at risk of developing a life-threatening condition called a pulmonary embolism.
Cardiac Arrest and Sudden Death
An enlarged heart may interfere with the normal rhythm of your heartbeat. If an enlarged heart causes your heartbeat to significantly decrease, the heart may be unable to pump blood throughout your body. Alternatively, an enlarged heart may cause your heartbeat to increase rapidly, which severely interferes with the heart's ability to pump blood through the body. These alterations in the rhythm of the heart beat can cause fainting to occur in some people. In severe cases, the heart may stop--a condition called cardiac arrest--which can lead to sudden death.
