Patients with HCM may have no symptoms for many years. However, as the disease progresses, patients often develop a variety of symptoms which typically fall into categories of heart failure, angina or arrhythmia-related.
HCM symptoms include
- Lightheadedness or passing out (syncope) – Lightheadedness should be evaluated thoroughly at a specialized center to look for dangerous arrhythmias (ventricular tachycardia or atrial fibrillation). Lightheadedness and syncope may also be related to left ventricular outflow tract (LVOT) obstruction. In these cases, medical therapy and other procedures may improve the symptoms.
- Shortness of Breath (dyspnea) – Patients with HCM can develop heart failure; that is, a backup of fluid in the lungs and legs. This occurs when the heart cannot pump out the requisite amount of blood, which also leads to significant fatigue. Moreover, some patients with HCM develop a leaky valve (mitral regurgitation) and elevated lung pressures (pulmonary hypertension), compounding the shortness of breath. Finally, those with severe LVOT obstruction are particularly affected, and may not be able to walk even a few feet without shortness of breath.
- Chest Pain – Because the heart muscle thickens with HCM, it requires more blood. Therefore, even if patients don’t have atherosclerosis, they may get angina. Moreover, patients with HCM are not immune to typical coronary disease, and can develop heart blockages like others of similar age, especially if they have the typical risk factors of smoking, diabetes, high blood pressure and high cholesterol. Stress testing and cardiac catheterization are often used to determine the cause of chest pain in patients with HCM.
- Palpitations – HCM can cause a variety of arrhythmias — from simple “extra beats” to atrial or ventricular tachycardias and fibrillation. Those with palpitations may benefit from further testing, including Holter monitoring or electrophysiology testing.
- Sudden Cardiac Death – Patients with HCM are at increased risk of sudden death, at a rate of 1-2% per year. Because of the muscle abnormality, the heart is irritable and may trigger arrhythmias, which drop the blood pressure to dangerous levels that don’t support life.