Definition and Overview
Cardiomyopathy is the general term for any abnormalities of the muscles of the heart (cardiac muscles).
The body has three types of muscles: skeletal, smooth, and cardiac. The cardiac muscle is unique among all of them since it’s the only type of muscle found in one organ, which is the heart.
The heart, meanwhile, is a muscular organ that is located in between the lungs. It is composed of four chambers, which are also known as rooms, as well as valves. They are connected to blood vessels, namely, arteries and veins. While the veins transport blood supply from the body to the heart, the arteries deliver blood all around the body from the heart. In order for the body to function well, particularly in terms of blood circulation, the heart needs to pump blood around a hundred thousand times every day. To do that, the organ relies on the cardiac muscles.
These muscles move involuntarily and automatically. Whether a person is doing something or whether the organ is stimulated by a device such as a pacemaker, the muscles continue to work.
However, usually for some unknown reason, the muscles of the heart change in size and shape. They can become rigid (restrictive), dilated, or thickened (hypertrophic). There are also other types of cardiomyopathy that don’t belong into any of these categories. In rare instances, the right ventricle becomes scarred or the scarred tissue replaces the healthy one, a condition called ARVD (arrhythmogenic right ventricular dysplasia).
Either way, when the muscles are affected, the heart may lose its ability to pump blood more efficiently. It may also lead to abnormal heart rhythm, a condition called arrhythmia.
Although many people with cardiomyopathy are able to live normal lives, when left unmonitored or untreated, the condition may cause heart failure and other cardiovascular diseases.
Causes of Condition
Until today, experts don’t really know the exact cause of cardiomyopathy. However, there are risk factors.
One, cardiomyopathy can either be acquired or hereditary. When it is acquired, it’s possible that the condition is caused by an underlying disease or certain symptoms such as high blood pressure. Meanwhile, some studies show that the risk of developing the condition increases when an immediate family member or relative has been diagnosed with one. Nevertheless, it should be clear that a person can only be genetically predisposed, which means it should not follow that the person will develop it.
In terms of age and gender, it all depends on the type of cardiomyopathy. For dilated cardiomyopathy, it’s more common in men and women who are between 20 and 60 years old. However, the chances of developing hypertrophic cardiomyopathy (or the thickening of the heart muscles) are equal for both men and women of any age. The rigidity of the muscles, meanwhile, is more common in older people. It’s rare for children to develop abnormalities in the cardiac muscles, but if they do have it, the cause of the condition is often considered unknown and is typically caused by genes.
Other possible causes of cardiomyopathy are:
- Lifestyle including smoking and alcoholism
- Infections, whether bacterial or viral, which attack the muscles of the heart
- Diagnosed heart disorder
- Previous heart attack
- Diseases that affect the liver and the thyroid
- HIV and AIDS
- Exposure to certain toxins and medications, such as chemotherapy drugs
- Illegal drugs such as amphetamines
- Poor diet and obesity
- Diabetes and other metabolic diseases or syndrome
- Any disease that has a direct impact on the heart such as abnormal buildup of iron (hemochromatosis) or protein (amyloidosis)
- Difficulty in breathing
- Feeling of tiredness even when at rest or minimal exertion
- Edema (swelling of the ankles, feet, or legs due to the buildup of excess fluid)
- Arrhythmia (abnormal heart rhythm)
- Chest pain
- Fainting spells
Despite the changes in the heart muscles, a person can still suffer from the condition and show no symptoms. Sometimes they are so mild that patients may not even notice them.
Who to See and Treatments Available
A cardiologist is the best specialist to diagnose, treat, and manage cardiomyopathy. As there’s still no single test to diagnose the condition, specialists typically run various tests to make an accurate diagnosis.
Usually, the doctor begins by looking into the medical and family history of the patient. This is followed by a physical exam by using the stethoscope to listen to the beating or the rhythm of the heart or any type of sound it may produce. Other common tests that are performed include the stress test, which measures the strength of the heart and whether it can cope with certain activities. A person with a possible heart problem often cannot last long during this type of exam. An electrocardiogram may also be used to create a picture of the heart including the shape and size using bounced sound waves. EKG, meanwhile, helps keep track of the electrical activity of the heart. All of these exams are non-invasive. Meanwhile, a chest X-ray can provide a general overview of the size and shape of the organ while cardiac catheterization can indicate how the blood flows through the chambers.
If cardiomyopathy is confirmed, the following steps may be undertaken:
Practice a much healthier lifestyle. These include avoiding smoking and drinking alcohol. It’s also important not only to lose weight but also to keep the body fat at an ideal range. Edema or excessive fluid retention may be controlled by reducing the intake of food that is high in sodium.
Take medications. The purpose of medications is often to manage the symptoms and potential risk factors of the condition such as elevated blood pressure and abnormal heart rhythm.
Surgery becomes an option only when the symptoms are already worse, the heart is already too damaged, or the medications are not working. During the surgery, an implantable device like a pacemaker may be used. A heart transplant is considered when the organ is severely diseased.
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