Cardiomegaly is a condition, commonly referred to as an enlarged heart or dilated heart, which is not considered a disease itself, but rather a clinical sign that may indicate the heart has increased in size.
This enlargement may affect the entire organ or be concentrated in one of the chambers, such as the left ventricle or the right ventricle.
Myocardium
The term myocardium refers to the muscle that makes up most of the heart and allows it to efficiently pump blood to the rest of the body. This tissue is composed of muscle fibers that are able to contract in a coordinated and rhythmic manner.
The myocardium and cardiomegaly are related, since any alteration in the structure or function of this muscle can trigger heart enlargement, as in the case of cardiomyopathies.
This enlargement may result from adaptive mechanisms that initially attempt to compensate for overload but, in the long term, may become harmful.
Cardiomyopathy
Cardiomyopathy is a group of diseases that directly affect the heart muscle, altering both its structure and its function, and it is considered an important cause of cardiomegaly.
Cardiomyopathies are classified into different types:
- Dilated cardiomyopathy: characterized by enlargement of the heart chambers and reduced pumping function; it may be caused by viral infections, alcoholism, or genetic predisposition.
- Hypertrophic cardiomyopathy: the heart muscle thickens abnormally, especially the left ventricle, making it harder to fill and pump blood; it is a hereditary disease and one of the main causes of sudden death in young athletes.
- Restrictive cardiomyopathy: the walls of the heart become stiff and lose their ability to relax properly, which affects ventricular filling; it can be caused by infiltrative diseases such as amyloidosis.
- Arrhythmogenic right ventricular cardiomyopathy: a rare condition affecting the tissue of the right ventricle, where muscle fibers are replaced by fatty or fibrous tissue.
Cardiomyopathies are a key factor in cardiomegaly, since myocardial damage forces the heart to structurally adapt in order to maintain pumping function.
Why does the heart grow?
Heart enlargement occurs due to a series of physiological and pathological mechanisms that attempt to compensate for increased workload or functional insufficiency of the myocardium.
Among the main causes are:
- In chronic high blood pressure, the elevated pressure forces the heart to work harder to pump blood, and over time this causes the myocardium to thicken.
- Faulty valves, which may result from stenosis or valvular insufficiency, can cause pressure or volume overload in the heart chambers.
- When the heart cannot pump blood efficiently, it attempts to compensate by dilating its chambers.
- Certain congenital structural abnormalities, such as ventricular septal defects, can cause volume overload and heart enlargement.
- Severe anemia or hyperthyroidism result in increased metabolic demand, forcing the heart to pump more blood and potentially leading to hypertrophy or dilation.
- Some viral infections can inflame the myocardium, weaken it, and enlarge the heart.
- Excessive alcohol consumption or exposure to certain drugs can weaken the heart muscle and contribute to cardiomegaly.
Depending on the origin of cardiomegaly, different treatment approaches may be followed. On one hand, controlling underlying diseases such as reducing blood pressure, managing heart failure, or treating infections is essential.
There are various medications, such as beta-blockers, ACE inhibitors, or diuretics, that also help relieve symptoms and improve heart function.
Surgery may be used for more severe cases, such as valve replacement, implantable defibrillators, or even a heart transplant.
Although cardiomegaly is not a disease in itself, it is a sign of the presence of other medical conditions that are affecting a person’s health.
Reaching an accurate diagnosis and providing early management of this condition, as well as its underlying causes, improves both quality and life expectancy.
At the ABC Medical Center’s Cardiovascular Center, we can provide you with specialized care. Contact us!
Fuentes:
Mayo Clinic, Texas Heart,Kids Health
