Cardiomyopathy, hypertrophic

Hypertrophic Cardiomyopathy (HCM) is a condition characterized by the thickening of the heart muscle, which can lead to various cardiac issues, including heart failure, arrhythmic beats, and sudden cardiac death. HCM is a primary disease of the myocardium (the muscle of the heart), where the cells enlarge and cause the walls of the ventricles (usually the left ventricle) to thicken without any obvious cause.

Etiology

Hypertrophic Cardiomyopathy is often inherited in an autosomal dominant pattern, meaning a mutation in just one of the copies of the gene is sufficient to cause the disorder. The condition is associated with mutations in several genes related to cardiac muscle proteins. These mutations affect the heart muscle's structure and function, leading to the characteristic thickening observed in HCM.

Pathophysiology

In HCM, the myocardial hypertrophy (thickening of the heart muscle) can lead to the obstruction of blood flow out of the ventricle (outflow tract obstruction), particularly during exercise when the heart beats more forcefully. This obstruction can cause symptoms such as shortness of breath, chest pain, and fainting. Additionally, the abnormal structure of the heart muscle can disrupt the normal electrical pathways, leading to arrhythmias (irregular heartbeats).

Symptoms

Symptoms of Hypertrophic Cardiomyopathy can vary widely among individuals. Some people may be asymptomatic, while others may experience:

• Shortness of breath, especially during exercise
• Chest pain, often related to physical activity
• Palpitations or feeling of rapid, fluttering, or pounding heartbeats
• Fainting, especially during or just after exercise or exertion
• Fatigue
• Dizziness

Diagnosis

Diagnosis of HCM involves a combination of medical history, physical examination, and diagnostic tests, including:

• Echocardiogram: An ultrasound of the heart that can visualize the thickened heart muscle.
• Electrocardiogram (ECG): A test that records the electrical activity of the heart and can detect abnormal rhythms.
• Cardiac MRI: Provides detailed images of the heart's structure and function.
• Genetic testing: Can identify mutations in genes associated with HCM.

Treatment

Treatment for Hypertrophic Cardiomyopathy focuses on managing symptoms, preventing complications, and reducing the risk of sudden cardiac death. Options include:

• Medications: Beta-blockers, calcium channel blockers, and antiarrhythmic drugs can help control heart rate, reduce symptoms, and prevent arrhythmias.
• Surgical and non-surgical procedures: Septal myectomy (surgical removal of a portion of the thickened septum) or alcohol septal ablation (a non-surgical procedure that uses alcohol to thin the thickened heart muscle) can be considered for patients with severe symptoms.
• Lifestyle changes: Patients are often advised to avoid competitive sports and strenuous activities that can increase the risk of sudden cardiac death.
• Implantable cardioverter-defibrillator (ICD): For patients at high risk of sudden cardiac death, an ICD can be implanted to detect and correct dangerous arrhythmias.

Prognosis

The prognosis for individuals with Hypertrophic Cardiomyopathy varies. Many people live a normal life span with mild symptoms or none at all. However, individuals with severe symptoms or a high risk of sudden cardiac death may face significant limitations. Early detection and appropriate management are crucial in improving outcomes.