A “Big” Problem: Determining If Your Enlarged Heart Is A Good Thing Or Indicator Of Bad Health

One of the biggest indicators of heart disease is cardiomegaly. Cardiomegaly is a condition more commonly known as an "enlarged heart," and it can indicate a serious medical condition--or supreme fitness. When the left ventricle region of your heart is particularly enlarged, it is not always easy to determine whether or not your heart is functioning efficiently because you are athletic, or poorly because you are suffering from heart disease. Here is an introduction to cardiomegaly, the left ventricle, and the importance of determining whether your heart is enlarged as a result of great health or poor health.

Where is the Left Ventricle?

The heart is divided into four main quadrants: the right atrium, the left atrium, the right ventricle, and the right ventricle. Blood enters the heart through the right atrium and is pumped to the right ventricle, which passes it through the lungs. The lungs enrich the blood with oxygen and send it back to the heart through the left atrium, which pumps it to the left ventricle. The left ventricle then pushes the blood out into the body's veins, and the process begins all over again.

What if the Left Ventricle is Enlarged?

When you feel your heart beat, you are actually experiencing your left ventricle pushing a percentage of your heart's blood out and into the body. The percentage of blood that your left ventricle pushes out is called your "ejection fraction"; a normal, healthy ejection fraction is above 55%.

If you have an enlarged heart, particularly in the left ventricle, your ejection fraction is potentially lower than 55%. This could mean that you are suffering from some form of heart disease, or it could also mean that you have what is commonly referred to as "athlete's heart."

When is an Enlarged Left Ventricle Good, and When is it a Sign of a Health Condition?

At first blush, it is often difficult to determine whether an enlarged heart, and particularly an enlarged left ventricle, is the side effect of endurance training or a heart condition. This is because, in both cases, the ejection fraction is frequently much lower than the 55% marker. If you are an endurance athlete, like a cyclist or marathon runner, then you might have an enlarged heart and low ejection fraction because you are very fit; as a result, your resting heart rate is probably lower than average, and your heart is capable of storing more blood than a person with a normal-sized heart. Thus, your heart will pump out the amount of blood that the rest of your body needs, but you have a considerable amount of blood still stored in your heart, so your ejection fraction will, naturally, be a lower percentage.

On the other hand, if you have an enlarged heart because of heart disease, then your left ventricle will pump less than 55% of the heart's blood out to the rest of your body because your heart is weakened, the walls might be hardened, or the valves might not function correctly. This will lead to shortness of breath, abnormal heart beats, and even weight gain and lack of energy.

How Can You Tell the Difference?

If your doctor performs an electrocardiogram, or EKG, on your heart, you will know whether or not you have an enlarged heart. The EKG will not necessarily tell your doctor the cause of your enlarged heart, however.

If you are an endurance athlete and you do not experience the symptoms of heart disease or have a family history of heart disease, your doctor or cardiology specialist will probably conclude that your enlarged heart is not a health concern. If you or your doctor are still concerned about the possibilities of heart disease, you can refrain from endurance activities for a few months and have another EKG performed. This can help your doctor determine if your enlarged heart is the result of strenuous endurance activities, or the sign of a much more serious condition.