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More about Congestive Cardiomyopathy:
Definition Causes and symptoms Diagnosis Treatment Prognosis Prevention Resources |
Congestive cardiomyopathy may be caused by a number of conditions. Cardiomyopathy with a known cause is called secondary cardiomyopathy. When no cause can be identified, it is called primary cardiomyopathy or idiopathic cardiomyopathy. About 80% of all cases of cardiomyopathy do not have a known cause. Many heart specialists think that many cases of idiopathic congestive cardiomyopathy may be caused by a viral infection. Because cardiomyopathy may occur many years after a viral infection and viruses sometimes go undetected in laboratory tests, it is difficult to know if a virus is the cause. Some people have a weak heart from advanced coronary artery disease that causes heart muscle damage. This is sometimes called ischemic cardiomyopathy.
Conditions that can cause congestive cardiomyopathy are:
- Coronary artery disease
- Infections
- noninfectious inflammatory conditions
- alcohol and other drugs or toxins
- hypertension
- nutritional and metabolic disorders
- pregnancy.
Coronary artery disease is one of the most common causes of congestive cardiomyopathy. In coronary artery disease, the arteries supplying blood to the heart become narrowed or blocked. When blood flow to an area of the heart is completely blocked, the person has a heart attack. The heart muscle suffers damage when its blood supply is reduced or blocked. Significant recurrent muscle damage can occur silently. This damage can lead to congestive cardiomyopathy.
Infections caused by bacteria, viruses, and other microorganisms can involve the heart, causing inflammation of the heart muscle (myocarditis). The inflammation may damage the heart muscle and cause congestive cardiomyopathy. In the United States, the coxsackievirus B is the most common cause of viral congestive cardiomyopathy.
Myocarditis can also be caused by noninfectious disorders. For example, the conditions sarcoidosis, granulomatous myocarditis, and Wegener's granulomatosis cause inflammation and tissue death in the heart muscle.
Years of drinking excessive amounts of alcohol can weaken the heart muscle, leading to congestive cardiomyopathy. Other drugs and toxins, such as cocaine, pesticides, and other chemicals, may have the same effect.
High blood pressure (hypertension) puts extra pressure on blood vessels and the heart. This increased pressure makes the heart work harder to pump blood, which may thicken and damage the chamber walls.
Severe nutritional deficiencies can weaken the heart muscle and affect its pumping ability. Certain disorders of metabolism, including diabetes mellitus and thyroid disorders, can also lead to congestive cardiomyopathy.
Occasionally, inflammation of the heart muscle and congestive cardiomyopathy may develop late in pregnancy or shortly after a woman gives birth. This type of congestive cardiomyopathy is called peripartum cardiomyopathy. The cause of congestive cardiomyopathy in pregnancy is not known.
Congestive cardiomyopathy usually is a chronic condition, developing gradually over time. Patients with early congestive cardiomyopathy may not have symptoms. The most common symptoms are fatigue and shortness of breath on exertion. Unfortunately, sudden cardiac death is not uncommon with this condition. It stems from irregular heart rhythms in the ventricles (ventricular arrhythmias).
Patients with more advanced congestive cardiomyopathy may also have chest or abdominal pains, extreme tiredness, dizziness, and swelling of the legs and ankles.
— Toni Rizzo
