Do you have or recognize any of these in yourself or someone you care for?
If so, this should be addressed soon. See their doctor or your own doctor to get a full workup and make sure your heart is not enlarged.
You may not even have symptoms so recognize these causes early.
Causes*
An enlarged heart (cardiomegaly) can be caused by damage to the heart muscle or any condition that makes the heart pump harder than usual, including pregnancy. Sometimes the heart gets larger and becomes weak for unknown reasons. This condition is called idiopathic cardiomyopathy.
Conditions associated with an enlarged heart include:
Heart condition present at birth (congenital heart defect). Problems with the structure and function of the heart can cause the heart muscle to get larger and weak.
Damage from a heart attack. Scarring and other structural heart damage can make it harder for the heart to pump enough blood to the body. The strain can lead to heart swelling and eventual heart failure.
Diseases of the heart muscle (cardiomyopathy). Cardiomyopathy often makes the heart rigid or thick. It can make it harder for the heart to pump blood.
Fluid buildup in the sac around the heart (pericardial effusion). A collection of fluid in the sac that contains the heart can cause heart enlargement that can be seen on a chest X-ray.
Heart valve disease. Four valves in the heart keep blood flowing in the right direction. Disease or damage to any of the valves may interrupt blood flow and cause the heart chambers to get larger.
High blood pressure (hypertension). If you have high blood pressure, the heart may have to pump harder to deliver blood to the rest of the body. The strain can cause the heart muscle to grow larger and become weak. Be sure your blood pressure is under control.
High blood pressure in the arteries in the lungs (pulmonary hypertension). The heart has to work harder to move blood between the lungs and the heart. The strain may lead to thickening or enlargement of the right side of the heart.
Low red blood cell count (anemia). In anemia, there's a lack of healthy red blood cells to carry proper levels of oxygen to the body's tissues. The heart must pump more blood to make up for the lack of oxygen in the blood.
Thyroid disorders. Both an underactive thyroid gland (hypothyroidism) and an overactive thyroid gland (hyperthyroidism) can lead to heart problems, including an enlarged heart.
Too much iron in the body (hemochromatosis). Iron can build up in various organs, including the heart. This can cause the lower left heart chamber to swell.
Unusual protein deposits in the heart (cardiac amyloidosis). This rare disease causes a protein called amyloid to collect in the blood and get stuck in body organs, including the heart. Amyloid protein deposits in the heart cause an irreversible thickening of the heart wall. The heart has to work harder to fill with blood.
Aerobic exercise. In some athletes, the heart becomes enlarged as a response to frequent and prolonged exercise. Usually, this type of enlarged heart isn't considered a disease and doesn't need treatment. (Some athletes use steroids to bulk up, and this is not good for the heart)
Fat around the heart. Some people have extra fat around the heart that can appear on a chest X-ray. Unless there are other heart conditions associated, no treatment is necessary.
*https://www.mayoclinic.org/diseases-conditions/enlarged-heart/symptoms-causes/syc-20355436
