HCM

HYPERTROPHIC CARDIOMYOPATHY

Cardiomyopathy is a general term applied when the heart muscle is abnormal without any apparent reason.

The word hypertrophic means thickening, HCM is thus an increased thickness of the heart muscle. This thickening is usually seen in the left ventricular septum without change to the size of the ventricular cavities. Hypertrophic Cardiomyopathy (HCM) is a genetic condition, which usually shows a familial pattern. In some cases abnormalities of the mitral valve structure may be present.

When the heart muscle of a patient with HCM is examined under a microscope the muscle is abnormal. The muscle cells are mis-aligned, irregular or disorganised and are said to display myocardial disarray.

Ventricular tachycardia or atrial fibrillation arrhythmias are often experienced by a patient with HCM. These arrhythmias can cause sudden death in a patient with hypertrophic cardiomyopathy.

It is possible that in the future some drugs may decrease the degree of heart muscle thickening but it will not be possible to return damaged muscle to normal.

Symptoms may include; sudden shortness of breath at night (paroxysmal nocturnal), fainting (syncope), fatigue and palpitations.

Holter monitoring (24 hour monitoring) may show; premature ectopic beats from the ventricles, supraventricular tachycardia, ventricular tachycardia and atrial fibrillation.

An ECG test may reveal; mitral regurgitation, IVS hypertrophy or a high pressure gradient between the LV outflow and the ascending aorta.

Patients with HCM should avoid competitive sport, HCM is the cause of a high number of sudden deaths in athletes.

Thickening of the muscle can occur due to involvement in sports, this thickening should not be confused with HCM. Muscle thickening can occur in patients with high blood pressure.

Dilated Cardiomyopathy

The word dilated means enlarged, DC is thus an enlarged heart, this is caused by weakening of the heart muscle.

Dilated cardiomyopathy may be caused by an earlier heart attack, part of the heart muscle may have died due to a lack of blood and oxygen, this weakens the rest of the muscle and it enlarges (ischemic cardiomyopathy) with time.

Symptoms may include; shortness of breath with activity, sudden shortness of breath at night (paroxysmal nocturnal), difficulty sleeping, fainting (syncope), collection of fluid in feet and legs, fatigue and palpitations. Severe arrhythmia can cause palpitations that may lead to syncope and possible sudden death.

DC may be inherited and is known as familial DC.

Idiopathic Dilated Cardiomyopathy IDC

The word idiopathic means of unknown cause, thus IDC is an enlarged heart without apparent cause.

Familial Cardiomyopathy

Families with a history of cardiomyopathy should be examined on electrocardiogram and echocardiogram machines.