Hypertrophic cardiomyopathy (HCM) is very common condition that is often the cause of sudden death in young people, including young atheletes. Despite this it can affect people of all ages and affects both men and women equally.
Hypertrophic cardiomyopathy occurs when the heart muscle (myocardium) becomes abnormally thick (hypertrophied), thus making it harder for the heart to pump blood properly.
Because Hypertrophic cardiomyopathy has very few or no symptoms it often goes unnoticed and undiagnosed until it is too late. In some cases of HCM, the thickened heart muscle can cause shortness of breath, chest pain or problems in the heart’s electrical system, resulting in the occurrence of arrhythmias (life-threatening abnormal heart rhythms).
People with hypertrophic cardiomyopathy have a genetic mutation that causes the heart muscle to grow unusually thick, plus myofiber disarray, an abnormal arrangement of heart muscle cells. This disarray can contribute to arrhythmia in some people.
Most people with hypertrophic cardiomyopathy have a form of the disease known as obstructive hypertrophic cardiomyopathy, in which the wall (septum) between the two bottom chambers of the heart (ventricles) becomes enlarged which causes an impediment of blood flow out of the heart. The severity of this disease can vary widely among patients.
Hypertrophic cardiomyopathy does not always occur with significant blocking of blood flow, however, the heart’s main pumping chamber (left ventricle) can become stiff, reducing the amount of blood the ventricle can hold and the amount pumped out to the body with each heartbeat. This is referred to as nonobstructive hypertrophic cardiomyopathy.
Hypertrophic cardiomyopathy is usually an inherited disorder with the odds of a child inheriting hypertrophic cardiomyopathy from the parent with the same condition being about 50%. Because of this, any close relatives of a person with hypertrophic cardiomyopathy should be tested for the disease.
Although many people with HCM don’t experience any significant health problems there can be some complications, such as:
The first symptom of hypertrophic cardiomyopathy among many young patients is sudden collapse resulting in a possible death. This can be caused by the blockage of blood from the heart to the rest of the body or by very abnormal heart rhythms (arrhythmias).
Some patients however have no symptoms and may not even realize they have the condition until it is found during a routine medical check up.
Some common symptoms are:
The goal of treatment is to prevent sudden cardiac death in people at high risk whilst relieving their symptoms. Specific treatment varies depending on the severity of your symptoms.
Possible treatment options include:
To ensure that your heart can pump more efficiently, you may be given medications to slow down and relax the heart muscle. Calcium channel blockers such as verapamil (Verelan, Calan, Covera-HS) or diltiazem (Cardizem, Tiazac, Dilacor XR), beta-blockers such as metoprolol (Lopressor, Toprol), propranolol (Inderal, Innopran XL) or atenolol (Tenormin), or medications to control your heart rhythm such as amiodarone (Cordarone, Pacerone) or disopyramide (Norpace) may be recommended.
If you have atrial fibrillation, in order to reduce the risk of clot development, your doctor may prescribe blood thinners such as warfarin (Coumadin, Jantoven), dabigatran (Pradaxa), rivaroxaban (Xarelto) or apixaban (Eliquis).
This is an open-heart procedure in which the surgeon removes a section of the thickened, overgrown septum between the ventricles. Doing this helps to improve blood flow and reduces the level mitral regurgitation. There are different approaches that can be taken, depending on the location of the thickened heart muscle. Surgeons may sometimes perform mitral valve repair at the same time as a myectomy.
If the medications you’ve been prescribed don’t relieve your symptoms a myectomy may be necessary. Most people who have a myectomy experience no further symptoms. Septal myectomy is only available in certain medical centers that specialize in the treatment of hypertrophic cardiomyopathy.
By injecting alcohol through a long, thin tube (catheter) and into the artery that is supplying blood to the thickened muscle, a small portion of the affected area can be destroyed. This procedure may improve your symptoms, however, possible complications with this procedure can occur. For example, heart block — a disruption of the heart’s electrical system. This requires implantation of a pacemaker.
If you have life-threatening arrhythmias (heart rhythms) such as ventricular tachycardia or ventricular fibrillation your doctor may suggest an ICD. An ICD is a small device that is implanted in your chest like a pacemaker and constantly monitors your heartbeat.
Your doctor will discuss the signs and symptoms you have, or are currently experiencing as well as reviewing your medical and family. Your doctor may order several tests to diagnose hypertrophic cardiomyopathy (HCM).
In order to diagnose hypertrophic cardiomyopathy your doctor will recommend an echocardiogram. This test allows your doctor to see whether your heart muscle is unusually thick or your blood flow is obstructed as well as whether your heart valves are moving normally.
Types of echocardiography include:
There may be additional tests ordered to search for other effects of hypertrophic cardiomyopathy. This can help your doctor determine the most appropriate treatment for your condition. Examples of these tests include: