Cardiomyopathy

Cardiomyopathy is a whole group of heart diseases. These diseases are not related to poor oxygenation (ischemia) of myocardium unlike the heart attack or angina pectoris.

Types of cardiomyopathy

Hypertrophic cardiomyopathy

The cause of this disease is not fully understood. It is probably related to genetics as it often has a familial incidence. There is hypertrophy of myocardium, which can be so enlarged that it becomes a barrier to the blood flow through the heart. This leads to impaired function of the heart as a pump and it increases risk of heart failure and dangerous arrhythmias including ventricular fibrillation. You can find more details in text dedicated to the hypertrophic cardiomyopathy.

Dilated cardiomyopathy

Dilated cardiomyopathy also causes enlargement of the heart but this is not due to hypertrophy but because of its excessive dilation. The causative factors are also unclear but we suspect some viral infections, chronic alcoholism and genetic conditions.

Restrictive cardiomyopathy

This is a rare form of cardiomyopathy. The heart muscle looses flexibility and elasticity because of deposits of solid connective tissue. This undermines the pumping ability and causes symptoms of heart failure. The prognosis is usually not good.

Arrhythmogenic cardiomyopathy (dysplasia) of the right ventricle

This is a very rare cardiomyopathy that is caused by replacement of heart muscle of the right ventricle by connective and adipose tissue. The newly formed tissue is very risky of development of various arrhythmias.

Symptoms

Generally speaking, cardiomyopathy can cause symptoms heart failure (shortness of breath, fatigue, syncope with unconsciousness, leg swelling, etc.) or an arrhythmia or both. There is a variety of possible arrhythmias including relatively benign such as atrial fibrillation and life-threatening (e.g. ventricular fibrillation).

Diagnosis

In addition to medical history and physical examination (some cardiomyopathies may cause a heart murmur), it is important to evaluate ECG (signs of heart failure, arrhythmias) and perform the echocardiography. Coronary angiography is necessary to distinguish cardiomyopathies from ischemic conditions as the cardiomyopathies do not have significantly narrowed coronary arteries. Doctors in specialized cardiology departments can perform biopsy of the heart muscle with a fine needle to a histological examination.

Treatment

We usually prescribe drugs to protect the heart muscle and prevent occurence of arrhythmias (ACE-inhibitors, beta-blockers). Symptoms of heart failure are treated by diuretics. In hypertrophic cardiomyopathy, a part of the enlarged cardiac muscle must be surgically removed to allow the blood a free passage. When there is a high risk of serious arrhythmias, it is necessary to implant the so-called ICD (implantable cardioverter defibrillator) device. The ICD is a small box similar to a classic pacemaker. ICD monitors the heart rhythm and in case of a serious arrhythmia, it emits a strong electric signal to restore the normal heart rhythm.