Hypertrophic cardiomyopathy (HCM) is a genetic condition that results in the thickening of the muscle walls in the left ventricle of the heart.
In HCM, muscles in the walls of the heart may become stiff, making it more difficult for the heart to pump blood throughout the body. An enlarged muscle wall can also take up more space in the left ventricle, reducing the volume of blood that the heart can push out with each beat.
There are two types of HCM: obstructive and nonobstructive.
Obstructive HCM is the more common type, affecting up to
The symptoms of HCM vary considerably from person to person. In many cases, enlargement of the heart muscles begins early in adolescence or adulthood, but symptoms may not start until later in life.
For this reason, many people with HCM may not know they have the condition for many years.
When symptoms do develop, they may be mild or minimal at first. The most common symptoms are:
- shortness of breath, especially with activity
- chest pain, especially with activity
- fainting (syncope)
- dizziness or lightheadedness
- fluttering or pounding heartbeats (palpitations) or abnormal heart rhythms
- excessive tiredness
- swelling in the abdomen, legs, ankles, or feet
- sudden death
HCM is a progressive disease, and symptoms may appear or become worse over time.
For most people with HCM, the primary goal of treatment is symptom management and prevention of other heart complications. This may involve medications, procedures, or a combination of the two.
The medications that healthcare professionals most commonly use in HCM treatment are:
- calcium channel blockers
- antiarrhythmic medications
In April 2022, the
This medication, Camzyos (mavacamten), works by reducing heart muscle contractions. Because this may increase the likelihood of heart failure in some cases, Camzyos is available only through limited programs with careful monitoring requirements.
Doctors may also recommend implantable heart devices to decrease the risk of sudden cardiac death. This category of devices includes:
- implantable cardioverter defibrillators
- cardiac resynchronization devices
In rare but serious cases, if advanced heart disease occurs, a person may need a heart transplant.
For people with and without symptoms, a healthcare professional may recommend certain
HCM is a genetic condition, which means it is the result of a mutation in certain genes that regulate heart muscle activity. Environment and lifestyle do not appear to play a role in the development of HCM but may affect the severity of symptoms.
In most cases, HCM follows an
However, not everyone with a gene mutation associated with HCM develops signs or symptoms of the condition. Scientists and medical professionals are still trying to understand why this happens.
Because not everyone with HCM develops symptoms, it can be difficult to estimate the actual prevalence in the population. Experts have historically estimated that HCM affects about
The primary risk factor for HCM is a family history of heart disease. Nearly
The risk of symptoms of HCM also increases with age. Enlargement of heart muscles can begin early in life, but symptoms may not appear for several decades. This means that many people do not receive an HCM diagnosis until later in life.
In most cases, especially with treatment, HCM is a manageable condition without a high likelihood of complications. However, muscle strain and abnormal electrical rhythms in the heart can increase a person’s likelihood of developing other severe heart conditions,
- heart failure
- arrhythmias, such as atrial fibrillation
- blood clots and stroke
- infection of the heart valves
- sudden cardiac death, in rare cases
People with HCM may also be at risk for complications in other conditions that put strain on the heart, such as pregnancy.
Because HCM is genetic, prevention
If a person has a family history of HCM or heart disease, they may consider genetic testing and counseling with a licensed genetic counselor to help with family planning.
Below, we answer a few frequently asked questions about hypertrophic cardiomyopathy.
What is the life expectancy of someone with hypertrophic cardiomyopathy?
In most cases, people with HCM can expect to have a typical life expectancy.
Because the condition is progressive, complications may develop over time that require additional care to reduce the likelihood of heart-related death. Healthcare professionals generally recommend regular monitoring and preventive treatment to minimize these risks.
Can you survive hypertrophic cardiomyopathy?
Most people can expect to live typical, uninterrupted lives with HCM. While the condition does increase the likelihood of developing heart-related complications, the risk of heart-related death is low.
- 0.6% for sudden heart-related death
- 0.2% for heart failure-related death
- 0.1% for stroke-related death
With preventive care and proactive monitoring, people can avoid many complications of HCM or detect them early, which can increase the likelihood of recovery.
At what age does hypertrophic cardiomyopathy develop?
In many cases, muscle thickening begins early in adolescence or adulthood. Nearly
Symptoms of HCM may not be present when HCM develops or may be mild. Even after heart thickening begins, people may notice symptoms for several years or decades.
HCM is a chronic heart condition that can worsen over time. Most people with HCM have a typical life expectancy and do not experience severe complications or major limitations to their daily activities.
A healthcare professional may prescribe medications to help manage symptoms, arrhythmias, and heart failure and reduce the risk of complications. In serious cases, surgical and nonsurgical procedures may be necessary to help restore blood flow in the heart.
HCM is not preventable in people who have a related genetic mutation. However, proactive screening and management, such as medications and lifestyle strategies, can help people reduce the signs and symptoms of HCM.