The cause of the disease is not clearly explained. There is probably a genetic condition and a change of correct blood flow through the heart muscle. No matter the reason, the consequence is hypertrophy and thickening of the heart muscle.
The heart muscle is hypertrophic, especially the septum (tissue dividing the ventricles). The heart becomes enlarged and poses increased resistance to the blood flow. Diseased myocardium is more susceptible to occurrence of lethal arrhythmias including ventricular fibrillation. Therefore, hypertrophic cardiomyopathy is directly associated with increased risk of sudden death. As time passes by, the patient suffering from hypertrophic cardiomyopathy may develop symptoms of heart failure such as shortness of breath, leg swelling, dizziness, fatigue and general inefficiency. Some patients complain of palpitations and chest pain.
Any patient having the above mentioned symptoms should be examined. By physical examination we can hear a heart murmur (because of disrupted blood flow through hypertrophic heart). ECG of such patient may include signs of overload of heart ventricles and probably even other pathologies. In chest X-ray we can see pathological enlarged heart shadow. The best examination method is the echocardiography that confirms heart hypertrophy and helps us to evaluate the actual blood flow. Coronary angiography usually confirms relatively healthy coronary arteries.
Conservative therapy includes regular administration of drugs protecting the heart muscle and reducing the risk of arrhythmias such as beta-blockers or calcium channel blockers. Anti-arrhythmic agents may be given to lower the risk of serious arrhythmias and there is a possibility of ICD implantation for very risky patients. ICD is an abbreviation for “implantable cardioverter defibrillator”. ICD is a small box resembling classic pacemaker. It is implanted under the skin of the chest with its electrodes in close contact with the heart muscle. ICD monitors the patient's heart rhythm and in case of a serious arrhythmia it sends a strong electric impulse to “reset” the arrhythmia and restore normal heart rhythm.
Significantly increased septum between the ventricles blocking the blood flow can be solved by percutaneous septal ablation or by cardiac surgery.