Hypertrophic Cardiomyopathy
Hypertrophic Cardiomyopathy Causes
In patients with hypertrophic cardiomyopathy, there is a disruption of the normal alignment of muscle cells, a condition known as myocardial disarray. HCM also disrupts the heart's electrical function. HCM is passed on to offsprings via autosomal dominancy, and believed to be the result of a mutation of one of many genes. A mutated myosin heavy chain, which is a component of the myocyte, is produced. The mutation of other genes associated with HCM include cardiac actin, cardiac troponin T, alpha-tropomyosin, cardiac troponin I, cardiac myosin-binding protein C, and the myosin light chains.
Hypertrophic Cardiomyopathy Definition
Hypertrophic cardiomyopathy (HCM) is a defect in the muscle of the heart known as myocardium. This disease is characterized by the thickening (or hypertrophy) of the myocardium without any evident cause. HCM is believed to be the leading cause of sudden, unexpected cardiac arrest in any age group.
Hypertrophic Cardiomyopathy Diagnosis
An echocardiography may be done to determine aortic valve calcification or assess for a dilated ascending aorta. A physical examination to test for murmur of AI, pulse pressure after PVC, valsalva maneuver, and carotid pulsation is also recommended.
Hypertrophic Cardiomyopathy Symptoms and Signs
Symptoms of HCM are variable. Most afflicted patients are either asymptomatic or demonstrate only mild symptoms. Common signs of hypertrophic cardiomyopathy are shortness of breath (dyspnea), angina or chest pains, heart palpitations, lightheadedness, fainting, fatigue, and sudden cardiac death. Usually, HCM symptoms mimic the signs of congestive heart failure, but treatment is very different between the two. Risk for sudden death in HCM patients are stronger in young age groups (30 years old and below).
Hypertrophic Cardiomyopathy Treatment
Treatment for HCM must focus on managing risk for sudden cardiac death. Patients who may have high propensity for sudden cardiac death may undergo defibrillator therapy. Treating HCM focuses on lowering the ventricular outflow tract gradient and managing dyspnea, chest pain, and syncope. Medical therapy often involves administering beta-blockers (e.g. metoprolol, atenolol, bisoprolol, propranolol). When symptoms persist, disopyramide may be administered in conjunction with the beta-blockade. An alternative route is to substitute the beta-blocker with a calcium channel blocker like verapamil. Most HCM symptoms can be treated medically without necessitating surgical interventions. But more severe cases may require surgical septal myectomy, alcohol septal ablation or pacing.