Possible risks of enlarged hearts in infants, children and adults include heart failure, blood clots, heart murmurs and cardiac arrest, according to Mayo Clinic. Sudden death is also a possibility.
Heart failure is one of the major complications of an enlarged heart, and depending on what part of the heart is enlarged, different effects may be experienced, explains Mayo Clinic. An enlarged left ventricle, for example, may increase the risk of developing heart failure. Having an enlarged heart also increases the chance of blood clots, which can cause heart attacks and strokes.
An enlarged heart may also cause heart murmurs, reports Mayo Clinic. For people who have an enlarged heart, two out of four of the heart valves may not properly close. This can cause blood to flow back, causing a sound known as a murmur. Though this isn't necessarily dangerous, murmurs should be monitored by a doctor.
Cardiac arrest and sudden death may also occur when a person has an enlarged heart. This happens because an enlarged heart can negatively affect the way the heart beats, states Mayo Clinic. If blood comes into the heart too quickly or slowly, the heart can stop beating altogether. This can cause fainting or sudden death due to blood not being moved throughout the body.