Diagnosis

A doctor holds a stethoscope to a patient's chest An exam at Mayo Clinic

A health care provider listens to a person's heart at Mayo Clinic.

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Your health care provider will examine you and ask questions about your signs, symptoms, and medical and family history.

Tests

Your provider will likely order tests to diagnose hypertrophic cardiomyopathy (HCM) or rule out other conditions that can cause similar symptoms.

  • Echocardiogram. An echocardiogram is commonly used to diagnose hypertrophic cardiomyopathy. This test uses sound waves (ultrasound) to see if the heart's muscle is unusually thick. It also shows how well the heart's chambers and valves are pumping blood.
  • Electrocardiogram (ECG or EKG). Sensors (electrodes) attached to adhesive pads are placed on the chest and sometimes the legs to measure electrical signals from the heart. An ECG can show irregular heart rhythms and signs of heart thickening.

    Your health care provider may recommend monitoring your heartbeat at home. A portable ECG device (Holter monitor) can be worn for a day or more to record the heart's activity during daily activities.

  • Cardiac MRI. This test uses powerful magnets and radio waves to create images of the heart. It provides information about the heart muscle and how the heart and heart valves work. This test is often done with an echocardiogram.
  • Stress test. A stress test often involves walking on a treadmill or riding a stationary bike while the heart is monitored. Exercise stress tests help reveal how the heart responds to physical activity.

Treatment

The goals of hypertrophic cardiomyopathy treatment are to relieve symptoms and prevent sudden cardiac death in people at high risk. Treatment depends on the severity of symptoms. You and your health care provider will discuss the most appropriate treatment for your condition.

If you have cardiomyopathy and are pregnant or thinking about pregnancy, your health care provider might recommend that you see a doctor experienced in caring for women with high-risk pregnancies (perinatologist or maternal-fetal medicine specialist).

Medications

Medications can help reduce how strongly the heart muscle squeezes and slow the heart rate so that the heart can pump blood better. Medications to treat hypertrophic cardiomyopathy and its symptoms might include:

  • Beta blockers such as metoprolol (Lopressor, Toprol-XL), propranolol (Inderal, Innopran XL) or atenolol (Tenormin)
  • Calcium channel blockers such as verapamil (Verelan, Calan SR,) or diltiazem (Cardizem, Tiazac)
  • Heart rhythm drugs such as amiodarone (Pacerone) or disopyramide (Norpace)
  • Blood thinners such as warfarin (Jantoven), dabigatran (Pradaxa), rivaroxaban (Xarelto) or apixaban (Eliquis) to prevent blood clots if you have atrial fibrillation or the apical type of hypertrophic cardiomyopathy, which can increase the risk of sudden cardiac death.

Surgeries or other procedures

Several surgeries or procedures are available to treat cardiomyopathy or its symptoms. They include:

  • Septal myectomy. This open-heart surgery might be recommended if medications don't improve symptoms. It involves removing part of the thickened, overgrown wall (septum) between the heart chambers. Septal myectomy helps improve blood flow out of the heart and reduces backward flow of blood through the mitral valve (mitral regurgitation).

    The surgery can be done using different approaches, depending on the location of the thickened heart muscle. In one type, called apical myectomy, surgeons remove thickened heart muscle from near the tip of the heart. Sometimes the mitral valve is repaired at the same time.

  • Septal ablation. This procedure destroys the thickened heart muscle with alcohol. The alcohol is injected through a long, thin tube (catheter) into the artery supplying blood to that area. Possible complications include disruption of the heart's electrical system (heart block), which requires implantation of a pacemaker.
  • Implantable cardioverter-defibrillator (ICD). An ICD is a small device that continuously monitors the heartbeat. It's implanted in the chest like a pacemaker. If a life-threatening arrhythmia occurs, the ICD delivers precisely calibrated electrical shocks to restore the heart rhythm. Use of an ICD has been shown to help prevent sudden cardiac death, which occurs in a small number of people with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy and treatment options

Steve R. Ommen, M.D., Cardiovascular Diseases: The hypertrophic cardiomyopathy is a condition that has been under-diagnosed and overly feared throughout the world. In the United States alone, there are over a half a million people that have hypertrophic cardiomyopathy, many of whom are completely asymptomatic and unaware of their diagnosis. Some people can die suddenly. Sudden cardiac death occurs randomly without warning.

Hartzell V. Schaff, M.D., Cardiac Surgery: Over 2/3 of the patients will have obstruction. And the obstruction to the left ventricular outflow tract is an indication for operation in patients that have symptoms. So we know now that 2/3 of the patients with hypertrophic cardiomyopathy and obstruction are candidates for surgery.

Steve R. Ommen: Hypertrophic cardiomyopathy is the most common inherited cardiomyopathy or heart muscle disease. People are born with the genetics for it, but the hypertrophy doesn't appear to start developing until adolescence, growth spurts, or beyond. It is possible for infants to born with thick heart muscles, but that's really quite rare and usually more severe expressions of the disease. And it's also been described as not coming on until people were in their fifth or sixth decade of life. So really, the onset can be at any time of life. And certainly the symptoms can occur throughout life.

Hartzell V. Schaff: The common symptoms that patients have when they have obstructive hypertrophic cardiomyopathy are shortness of breath, angina-like chest pain and syncope. And unfortunately, some of these symptoms develop so slowly and over such a long time that the patients don't really understand how limited they are.

Steve R. Ommen: For patients who have symptoms due to hypertrophic cardiomyopathy, the first line of therapy is always to use medical management, medications. Usually, that's adding specific medications, but sometimes patients are on medications that can make their situation worse. And so some of the most effective therapy is removing the wrong agents, and then perhaps having to add in the right agents to help them with their symptoms down stream.

For patients who don't respond to those medical changes, or for whom those medications caused side effects that are intolerable, then that's when we move to things like surgical myectomy, which can more definitively relieve their symptoms.

Hartzell V. Schaff: The patients who are referred for surgery almost always have either failed medical treatment or have side effects from the medicines that limit them just as much as the symptoms from hypertrophic cardiomyopathy. So operation to relieve outflow tract obstruction is to relieve the symptoms. And in some patients, to allow them to get off of the medications that are having unwanted side effects.

Steve R. Ommen: Surgical myectomy has been a very successful operation for many of our patients. However, it is not utilized as much as it maybe could be in part owing to prior perceptions about increased risk with the operation, lack of universal availability of surgeons who can do it. But in the hands of expert centers, the complication rates are very low and our success rates are very high.

Hartzell V. Schaff: We now do a more extensive septal myectomy that extends towards the apex of the heart. And we've learned over the years that it's this distal portion of myectomy that's the most important in terms of relieving symptoms. The few patients who have had a second operation, who have been referred to us after having an operation that was unsuccessful, we found that the myectomy was not carried far enough into the ventricle. It's really not a regrowth of muscle. It's just an inadequate initial operation.

Steve R. Ommen: With surgical myectomy, the surgeon removes a portion of the hypertrophied septum, which is narrowing the path of blood, out of the heart. By doing this, it changes the direction the blood flows through the ventricle. It allows the mitral valve to function normally. And allows blood to leave the heart without increasing pressures or increasing forces. This muscle doesn't regrow over time. It is a permanent fix.

Hartzell V. Schaff: We found that it's rarely necessary to do something to the mitral valve. And the hazard with doing something to the mitral valve, where it turns out to be unnecessary, is there is a chance of injury. So we would prefer to do a septal myectomy, come off bypass, assess the mitral valve with an echocardiogram during surgery, before then addressing the mitral valve if there is residual regurgitation.

We can tell if the mitral regurgitation is relieved immediately after the myectomy once the aorta is closed and the heart is restarted. The echocardiogram is done in the operating room and we know right away whether the mitral regurgitation has been relieved. An operation is available for some patients that have non-obstructive hypertrophic cardiomyopathy. And these are patients with the apical distribution of hypertrophy.

Some of those patients have diastolic heart failure related to very small ventricular cavities. And in these patients, doing a transapical myectomy to enlarge the ventricle can improve their symptoms of heart failure.

Steve R. Ommen: While we see great results from the surgical myectomy as performed now, it is still something that should only be performed at true centers of excellence. Recent data that have come out have suggested that at low, medium, and even quote unquote "high volume" centers, there is a gradient of mortality, meaning it's highest at the low volume centers and lowest at the high volume centers.

But even those so-called high volume centers have mortality rates that are dramatically higher than what is reported from the true expert centers. And this is a procedure that should be done by those who are very familiar with this procedure, and doing a lot of them.

Hartzell V. Schaff: At Mayo Clinic, we've done over 3,000 operations for hypertrophic cardiomyopathy. We do 200 to 250 operations each year. The mortality for the procedure is less than 1%, especially for patients who are otherwise healthy.

Steve R. Ommen: One of the biggest parts of every interaction that I have with patients is helping them understand what their individual risk for sudden cardiac death might be, and whether they might consider having an implantable defibrillator. Our patients who have had surgery have a lower rate of sudden cardiac death and a lower rate for their defibrillators to discharge among those who have had them.

Hartzell V. Schaff: One of the things we've learned after doing septal myectomy is that actually the incidence of ventricular arrhythmia seems to be reduced. And this is shown in studies that look at defibrillator discharges and rates of sudden death.

Steve R. Ommen: The inheritance pattern of hypertrophic cardiomyopathy is autosomal dominant, which means each of the children of a patient with HCM has a 50/50 chance of inheriting this disease. We do recommend screening for all first-degree relatives, which is either genetic testing or echocardiographic-based surveillance. When a family has chosen to use echocardiography as their screening tool, we recommend that adult first-degree relatives get screened every five years. First-degree relatives who are adolescents or athletes, we usually screen every 12 to 18 months.

Hartzell V. Schaff: Septal myectomy cures the symptoms of hypertrophic cardiomyopathy when it relieves the obstruction. But of course, patients still have hypertrophic cardiomyopathy, still need to be followed by their physician for the other problems related to hypertrophic cardiomyopathy. But hopefully, are relieved of the shortness of breath, chest pain, or light-headedness that leads to the operation.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Lifestyle and home remedies

Lifestyle changes, such as the following, can reduce the risk of complications related to hypertrophic cardiomyopathy.

  • Exercising. You'll likely be able to engage in moderate-intensity exercise as part of a healthy lifestyle. If you want more-vigorous exercise, talk to your health care provider about your potential risks.
  • Eating a healthy diet. A healthy diet is an important part of maintaining heart health.
  • Maintaining a healthy weight. Maintaining a healthy weight will prevent excessive stress on the heart and reduce health risks associated with surgery or other procedures.
  • Limit or avoid alcohol. In some cases, irregular heart rhythms and blocked blood flow are triggered or worsened by alcohol use. Ask your health care provider how much alcohol, if any, is safe for you to drink. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
  • Having regular medical appointments. Your health care provider might recommend regular follow-up appointments to evaluate your condition. Let your provider know if you develop new or worse symptoms.

Coping and support

Being diagnosed with hypertrophic cardiomyopathy can cause a range of difficult emotions. Feelings of grief, fear and anger aren't uncommon.

To better manage your condition:

  • Manage stress. Find ways to help reduce emotional stress. Getting more exercise and practicing mindfulness are ways to reduce stress.
  • Seek support. Consider joining a support group. Support groups allow you to connect with others who have similar experiences.

Preparing for your appointment

You may be referred to a doctor trained in diagnosing and treating heart conditions (cardiologist). Here's some information to help you prepare for your appointment.

What you can do

When you make the appointment, ask about pre-appointment restrictions, such as changing your activity level or your diet. Make a list of:

  • Your symptoms and when they began
  • All medications, vitamins and supplements you take, including doses
  • Key medical information, including other diagnosed conditions and family history of heart disease
  • Questions to ask your health care provider

Questions to ask your health care provider might include:

  • What's the most likely cause of my symptoms?
  • What tests do I need?
  • What treatments can help?
  • What risks does my heart condition create?
  • How often will I need follow-up appointments?
  • Do I need to restrict my activities?
  • Should my children or other first-degree relatives be screened for this condition, and should I meet with a genetic counselor?
  • How will other conditions that I have or medications I take affect my heart condition?

Don't hesitate to ask other questions you have.

What to expect from your doctor

Your health care provider is likely to ask you a number of questions, such as:

  • How severe are your symptoms?
  • Have your symptoms changed over time? If so, how?
  • Does exercise or physical exertion make your symptoms worse?
  • Have you ever fainted?

What you can do in the meantime

Before your appointment, ask your family members if any relatives have been diagnosed with hypertrophic cardiomyopathy or have had unexplained, sudden death.

If exercise makes your symptoms worse, avoid strenuous exercise until you have seen your health care provider and received specific exercise recommendations.

Hypertrophic cardiomyopathy care at Mayo Clinic

May 24, 2022
  1. Maron MS. Hypertrophic cardiomyopathy: Clinical manifestations, diagnosis, and evaluation. https://www.uptodate.com/contents/search. Accessed Dec. 9, 2021.
  2. Hypertrophic cardiomyopathy (HCM). American Heart Association. https://www.heart.org/en/health-topics/cardiomyopathy/what-is-cardiomyopathy-in-adults/hypertrophic-cardiomyopathy. Accessed Dec. 9, 2021.
  3. AskMayoExpert. Hypertrophic cardiomyopathy (adult). Mayo Clinic; 2021.
  4. Hypertrophic cardiomyopathy (HCM). American College of Cardiology. https://www.cardiosmart.org/topics/hypertrophic-cardiomyopathy. Accessed Dec. 9, 2021.
  5. Brasswell Pickering EA. AllScripts EPSi. Mayo Clinic. Accessed Oct. 25, 2021.
  6. Onmen SR, et al. 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: Executive summary. Circulation. 2020; doi: 10.1161/CIR.0000000000000938.
  7. Cirino AL, et al. Hypertrophic cardiomyopathy overview. GeneReviews. 2021; https://pubmed.ncbi.nlm.nih.gov/. Accessed Dec. 9, 2021.
  8. Mankad, R (expert opinion). Mayo Clinic. Dec. 15, 2021.
  9. Dearani JA, et al. Surgery insight: Septal myectomy for obstructive hypertrophic cardiomyopathy — The Mayo Clinic experience. Nature Clinical Practice Cardiovascular Medicine. 2007; doi:10.1038/ncpcardio0965.
  10. Kirklin JW, et al. Surgical relief of diffuse subvalvular aortic stenosis. Circulation. 1961; doi:10.1161/01.cir.24.4.739.