Hearing the word “risk” at the doctor’s office can be scary. It’s natural for your mind to race when you’re sitting in that quiet exam room talking about the future of your heart health.

Hypertrophic cardiomyopathy (HCM) means your heart muscle has grown thicker than normal, which can make pumping blood more difficult. Historically, HCM was considered a condition with a high mortality rate. However, with modern management — including better risk assessment tools and protective devices — the outlook has improved dramatically.

When doctors talk about high risk or low risk, they’re using a tool to figure out exactly what you need — whether that’s standard checkups or extra safety measures. We’ll explore what risk really means, how doctors measure it, and what your category tells you about your care.

Decoding the Language of Risk

When doctors mention risk in HCM, they’re usually looking at the likelihood of sudden cardiac death (SCD) — a serious event in which the heart’s electrical system can fail.

The actual numbers are reassuring. Serious heart events only happen to roughly 1 percent of adults with this condition annually, and medicine has come a long way in treating it. The goal of risk assessment is to find the small percentage of people who might need extra protection.

Being placed in the high-risk category typically means you have one major risk factor or a combination of smaller ones that make the probability of cardiac arrest higher.

Think of it like checking the weather. A 60 percent chance of rain doesn’t guarantee you’ll get wet. It just means you should consider carrying an umbrella. Being told you’re high risk doesn’t mean a heart event is guaranteed. It just means the odds are high enough that your doctor wants to give you that umbrella, just in case.

Risk is dynamic and can change as you age. Your risk level is a snapshot of today rather than a permanent sentence. Risk can increase if the heart muscle thickens or scar tissue develops, or it can stabilize with good management. Regular follow-ups are the only way to know if your status has shifted.

Learning How Doctors Assess Risk

Doctors combine your medical history with advanced imaging to understand how well your heart pumps and how stable its electrical system is.

Identifying Major Risk Factors

Your healthcare team looks for several major markers:

• Family history — A close relative who passed away suddenly from heart issues, especially under age 50
• Unexplained syncope — Fainting spells without a clear reason, like dehydration
• Significant wall thickness — Heart muscle measuring 30 millimeters or more at its thickest
• Nonsustained ventricular tachycardia — Brief runs of rapid heartbeats caught on a portable monitor

Using Advanced Imaging Tools

Technology has improved how doctors see the heart. Specific imaging findings signal that the heart is under extra strain:

• Apical aneurysm — This is a small pouch at the tip of the heart.
• Ejection fraction drop — Ejection fraction shows how much blood your heart pumps with each beat. A drop below 50 percent is significant in HCM.
• Extensive fibrosis — Scarring covering 15 percent or more of the heart muscle can interrupt electrical signals.

Calculating the Score

Different medical groups use different formulas, and high risk thresholds vary by guideline.

When doctors mention risk in HCM, they’re usually looking at the likelihood of sudden cardiac death — a serious event in which the heart’s electrical system can fail.

The American Heart Association looks for major risk markers. Instead of calculating a specific percentage, they identify red flags — like extreme wall thickness or unexplained fainting. Having just one of these major markers can be enough to warrant a discussion about an implantable cardioverter defibrillator (ICD), a device that monitors your heart continuously and delivers a lifesaving shock if it detects an abnormal heart rhythm.

The European Society of Cardiology uses the HCM Risk-SCD calculator. You’re classified as high risk if it estimates your chance of SCD at 6 percent or higher over the next five years.

Both approaches answer the same question — does the safety of a protective device outweigh the surgical risks?

Interpreting Your Risk Category

Once your doctor gathers all the data, they’ll discuss where you fall. Understanding these categories helps you participate in treatment decisions.

Managing High-Risk Status

Being placed in the high-risk category typically means you have one major risk factor or a combination of smaller ones. This doesn’t mean you’ll definitely experience cardiac arrest. Being in the high-risk category means the probability is high enough that taking action makes sense.

For most people in this group, the next step is discussing an ICD. Your doctor will likely recommend either a transvenous device with a generator under the skin and wires inside the heart or a subcutaneous version (a larger generator placed under the skin, but without wires inside the heart).

An ICD is highly effective. Research shows that for every six or seven people who get an ICD, one life is saved. That’s considered a very favorable ratio in medicine.

Navigating Low-Risk Status

Landing in the lower-risk category is good news. However, low risk doesn’t mean zero risk. It means the statistical chance of cardiac arrest is low enough that an ICD would pose more risks than benefits. The action plan is watchful waiting, with annual or biannual echocardiograms and rhythm monitors to ensure your status hasn’t changed.

An important distinction to know is that risk and symptoms are different measures. You can be at lower risk for cardiac arrest while still experiencing daily symptoms like shortness of breath, chest pain, or palpitation. Your doctor will still treat symptoms with necessary medications and procedures.

Handling the Gray Zone

Many people fall into an intermediate category in which the risk isn’t clearly high or low. This is where shared decision-making becomes critical.

Your doctor will present the clinical data, but you provide the context. Some people prefer the safety net of an implanted device despite the surgical risks. Others prefer to avoid surgery unless it’s strictly necessary. Your anxiety level, lifestyle, and values are just as important as the numbers in making this choice.

Living Well With HCM

Your risk number is just one part of your story. Daily habits and mental well-being matter equally.

Moving Your Body Safely

If you were diagnosed years ago, you might have been told to avoid physical activity. But medical advice has changed. Now, movement is encouraged.

Current research shows that moderate-intensity recreational exercise is beneficial for almost everyone with HCM. Regular activity helps keep your heart muscle strong and boosts your overall health.

Low risk doesn’t mean zero risk. It means the statistical chance of cardiac arrest is low enough that you don’t need surgery.

Even athletes or those with higher-risk profiles might still be able to participate in sports. The key is a thorough discussion with a specialist to create a safety plan tailored to you.

Prioritizing Emotional Health

Living with a heart condition can be emotionally heavy. Unchecked stress can affect your life just as much as physical symptoms, so caring for your mind is as important as caring for your heart.

Use the power of community. Support groups and professional counseling are essential tools for a complete care plan. Managing your mental health is one of the most proactive things you can do to live well with HCM.

Taking the Next Step

Knowledge is power when it comes to HCM. The good news is that with today’s management, the risks are low, and you have significant control over your future.

You can start today with these steps:

• Organize your test results and medical records in one accessible place — whether that’s a folder on your phone or a binder at home.
• Connect with an HCM support community online or through your healthcare system. You’ll find both practical advice and emotional support from people who understand what you’re experiencing.
• Encourage your family members — parents, siblings, or children — to get screened through genetic testing or an echocardiogram, since HCM is often inherited but their risk profiles may differ from yours.

Most importantly, stay connected with specialists who understand HCM. If you’re uncertain about your risk category or treatment plan, scheduling time with a cardiovascular specialist will give you the clarity and confidence to move forward.

Join the Conversation

On MyHeartDiseaseTeam, people share their experiences with heart disease, get advice, and find support from others who understand.

How has your risk profile affected your daily life? Let others know in the comments below.