Introduction: Who Should Seek Diagnostic Evaluation

If you experience symptoms such as chest pain during physical activity, shortness of breath, dizziness, fainting spells, or a sensation that your heart is racing or fluttering, it’s important to see a healthcare professional promptly^[1]. These signs could indicate hypertrophic cardiomyopathy or other heart conditions that need medical attention. Many conditions can cause similar symptoms, which is why getting a proper checkup is essential to identify the exact cause and receive appropriate care.

Family history plays a crucial role in determining who should undergo testing for hypertrophic cardiomyopathy. If someone in your family has been diagnosed with this condition, you have an increased chance of having it too, since it often runs in families^[5]. In families with a known case of hypertrophic cardiomyopathy (HCM), which is a disease where the heart muscle becomes abnormally thickened, children of an affected parent have a 50% chance of inheriting the genetic change that causes the condition^[5]. This means that even if you feel completely healthy, screening may be recommended if a close relative has the disease.

It’s especially important to inform your healthcare provider if anyone in your family died suddenly before age 40. Sudden death in young family members can be a warning sign of undiagnosed hypertrophic cardiomyopathy, as this condition is the most common identifiable cause of sudden cardiac death in otherwise healthy people younger than 35, including well-trained athletes^[3][5]. Healthcare providers need this information to assess your risk and determine whether you need screening, even if you have no symptoms at all.

You should also seek immediate medical attention if you experience rapid or irregular heartbeat lasting more than a few minutes, or trouble breathing that doesn’t quickly resolve. Call emergency services right away, as these could be signs of serious complications^[1]. When symptoms appear during or just after exercise, this is particularly concerning and warrants urgent evaluation.

Classic Diagnostic Methods

The diagnostic process for hypertrophic cardiomyopathy typically begins with a thorough physical examination and discussion of your medical history. During the physical exam, your healthcare provider will listen to your heart using a stethoscope^[8]. They may hear a heart murmur, which is an unusual sound caused by turbulent blood flow through the thickened heart muscle. The provider will also check your pulse in your arms and neck, measure your blood pressure, and feel for any abnormal heartbeat in your chest^[7].

An echocardiogram is often the primary test used to diagnose hypertrophic cardiomyopathy^[8]. This test uses sound waves to create moving images of your beating heart, similar to how ultrasound is used during pregnancy. The echocardiogram allows doctors to see if your heart muscle is thicker than it should be and to measure how well your heart chambers and valves are pumping blood. It’s a painless procedure that provides detailed information about the structure and function of your heart without requiring any incisions or radiation exposure.

The echocardiogram can also reveal whether you have obstructive or nonobstructive hypertrophic cardiomyopathy. In the obstructive type, which affects about two-thirds of people with the condition, the thickened heart muscle blocks or reduces blood flow from the left ventricle to the aorta^[4]. In nonobstructive hypertrophic cardiomyopathy, the heart muscle is thickened but doesn’t obstruct blood flow. Testing should be performed to detect outflow obstruction both at rest and during provocation to determine which type is present^[11].

An electrocardiogram (ECG or EKG) is another essential diagnostic tool. This quick and painless test measures the electrical activity of your heart^[8]. Small sticky patches called electrodes are placed on your chest and sometimes on your arms and legs. These electrodes connect to a computer that records your heart’s electrical signals and prints or displays the results. An ECG can show irregular heartbeats and signs of heart muscle thickening. Many people with hypertrophic cardiomyopathy have abnormal ECG results even before their heart shows visible thickening on other imaging tests.

A Holter monitor or longer-term heart rhythm monitor may be recommended to record your heart’s activity over one or more days while you go about your regular activities^[8]. This small, portable ECG device helps detect irregular heart rhythms that may not appear during a brief office visit. Because dangerous heart rhythm problems can occur in hypertrophic cardiomyopathy, continuous monitoring provides valuable information about your heart’s electrical patterns throughout the day and night.

Cardiac magnetic resonance imaging (MRI) uses powerful magnets and radio waves to create detailed images of your heart^[8]. This test is often performed along with an echocardiogram to provide additional information about the heart muscle and how the heart and heart valves work. Cardiac MRI can show the exact location and extent of heart muscle thickening, which helps guide treatment decisions. Unlike CT scans or X-rays, MRI doesn’t use radiation, making it a safe option for detailed heart imaging.

A stress test may be performed to see how your heart responds during physical activity^[8]. This usually involves walking on a treadmill or riding a stationary bike while your heart is monitored. The test helps doctors understand whether exercise triggers symptoms or dangerous heart rhythms. Since many people with hypertrophic cardiomyopathy experience symptoms specifically during physical exertion, stress testing provides important information about your heart’s function under demanding conditions.

Cardiac catheterization is an invasive test that may be used in certain situations. During this procedure, a thin tube called a catheter is inserted into a blood vessel and guided to your heart^[7]. This allows doctors to measure pressures inside the heart chambers and assess blood flow. While not needed for every patient, cardiac catheterization can provide precise measurements of how severely blood flow is blocked in obstructive hypertrophic cardiomyopathy.

Healthcare providers will also work to distinguish hypertrophic cardiomyopathy from other conditions that cause similar heart changes. Hypertensive heart disease, which results from long-standing high blood pressure, can also thicken the heart muscle^[6]. Athlete’s heart, a normal adaptation to intense physical training, may cause heart muscle thickening that resembles hypertrophic cardiomyopathy but isn’t actually a disease^[6]. Other inherited conditions such as Fabry disease and Friedreich’s ataxia can also cause heart muscle thickening and must be ruled out^[6].

Genetic Testing and Family Screening

Genetic testing plays an increasingly important role in diagnosing hypertrophic cardiomyopathy and identifying family members who may be at risk. About 60% of patients with this condition have a known gene mutation in genes that control the production of heart muscle proteins^[3][5]. These genes provide instructions for making parts of the contractile machinery that allows heart muscle cells to work properly. When these genes have changes or mutations, the heart muscle can become abnormally thick.

Obtaining a detailed family history is crucial for risk stratification in affected patients^[3]. Your healthcare provider will ask about relatives who have been diagnosed with heart disease, who have had heart failure, irregular heart rhythms, strokes, heart attacks, heart transplants, or implanted heart devices. Information about family members who died suddenly, especially if they were younger than 40, is particularly important^[5]. This family health history should be updated regularly, and you should inform your healthcare provider about any new diagnoses, cardiac events, or sudden deaths in your family.

When someone in your family has been diagnosed with hypertrophic cardiomyopathy, genetic testing can look for the specific genetic changes that cause the condition^[5]. Testing should ideally start with the family member who has been diagnosed with the disease. Once the genetic change is identified in that person, other family members can be tested for that same change. This approach is more efficient than broad genetic screening and provides clearer answers about individual risk.

If genetic testing shows that you carry the genetic change for hypertrophic cardiomyopathy, you will need to see a cardiologist to check your heart for signs of the disease^[5]. Having the genetic mutation doesn’t necessarily mean you currently have symptoms or visible heart changes. Some people who have the changed gene may never develop the disease^[4]. However, knowing you carry the mutation means you need regular monitoring to detect early signs of heart muscle thickening.

When the genetic change that causes hypertrophic cardiomyopathy in a family is not known, parents, siblings, and children of the person with the condition will need to be checked for signs of the disease using heart imaging tests^[5]. Close family members of people diagnosed with hypertrophic cardiomyopathy may be screened with an echocardiogram or with genetic testing^[7]. This screening is recommended even for family members who have no symptoms, because early detection can lead to better health outcomes^[5].

Understanding Your Symptoms as Diagnostic Clues

Knowing the symptoms of hypertrophic cardiomyopathy is important, especially if you have a family history of the condition or if you have the genetic change that causes it. The most common symptoms include feeling tired or lacking energy, shortness of breath especially with physical activity, chest pain particularly during exercise, and fainting or feeling dizzy or lightheaded^[5]. Some people also experience swelling in their ankles, feet, legs, or stomach.

You may have several of these symptoms or none at all. The symptoms can be worse when you are dehydrated, because having less fluid in your body means your heart has less blood to pump with each beat^[6]. Many people don’t have symptoms in the early stages but develop them over time^[5]. This is why repeated monitoring based on your age and other factors is important even if you don’t currently have any signs or symptoms.

Some people with hypertrophic cardiomyopathy first discover they have the condition during a routine medical exam when they have no symptoms at all^[7]. In many young adults, the first symptom can be sudden collapse and possible death caused by highly abnormal heart rhythms or blockage that prevents blood flow from the heart to the rest of the body^[7]. This tragic possibility underscores why family screening and early diagnosis are so critical, even when a person feels completely healthy.