Arrhythmias occur when your heart beats irregularly because of an issue with its internal electrical system. While arrhythmias have many causes, like caffeine and even stress, you can also inherit them from your parents.
You might not be able to feel these irregular heartbeats, but if you have family members with heart conditions, you may want to talk with your doctor about your risk. Keep reading to learn about what types of heart arrhythmias are genetic, or inherited, and what you can do about them.
You inherit a lot of things from your parents, including the color of your eyes and how tall you will be. But not every genetic trait is a good one.
While sudden cardiac death is extremely rare, affecting just
Sometimes, the issue is limited to a malfunction in the electrical signals in the heart, the
What are genetics?
When you were conceived, 23 pairs of chromosomes served as a recipe for your development. The first 22 pairs are called autosomes, and they contain the bulk of your genetic information. The final pair are X or Y chromosomes and determine your sex assigned at birth.
Each chromosome contains genes or bits of information from each parent. This information determines what traits you will have as you develop.
In some cases, these genes can be flawed, or carry mutations that change the way certain systems in your body work. These mutations happen for many reasons and can come from either of your parents.
- Dominant. Many inherited heart arrhythmias are autosomal dominant conditions. This means that a mutated or altered gene was in the first 22 pairs of chromosomes that developed at your creation. When one parent has a copy of a mutated gene, the
Centers for Disease Control and Prevention (CDC)says you have a 50 percent chance of inheriting it.
- Recessive. With autosomal recessive conditions, you can receive one copy of a mutated gene from each parent. This means that each of your parents is a carrier of the condition. When your parents are both carriers, your chance of having an autosomal recessive condition passed on to you is about
25 percent. However, even if this gene is passed on to you, you may never develop symptoms.
Your heart operates using a complex electrical system that pulses through a detailed and delicate structure. Any time one of these electrical signals is off, or a part of the structure is damaged or formed incorrectly, it can create a host of issues.
- Primary electrical diseases. These are arrhythmias that develop from issues with electrical signals and not from structural issues in the heart.
- Secondary arrhythmia syndromes. Arrhythmias like these will develop with structural heart disease.
All inherited heart arrhythmias are considered to be relatively rare conditions, but the most common types are:
- atrial fibrillation
- long QT syndrome
- short QT syndrome
- catecholaminergic polymorphic ventricular tachycardia
- Brugada syndrome
Read on to learn about the main types of inherited heart arrhythmias.
Familial atrial fibrillation
Atrial fibrillation, also known as AFib or AF, is the most common type of heart arrhythmia overall. This condition involves the top chambers of the heart, which are known as the right and left atria.
In AFib, the right and left atria quiver and are not coordinated in pumping. This leads to compromised blood flow to the lower chambers of the heart, or the right and left ventricles.
AFib can cause blood to pool in the atria. This increases your chance of developing blood clots, which are potentially life threatening. A
This condition can develop with age, but recent studies have found that up to 30 percent of people with AFib inherited it. According to MedlinePlus Genetics, several genes have been linked to the development of familial AFib:
Many of these genes provide instructions as your heart forms on how its electrical channels should be “wired.” If these channels aren’t wired correctly, then ions — tiny particles with an electrical charge — will have trouble passing signals through the muscles of your heart.
Brugada syndrome is another type of electrical issue in the heart that causes the ventricles to beat irregularly or too fast. When this happens, your heart can’t pump blood out to the body effectively.
This can cause serious difficulties since many of your organs rely on a consistent and strong blood flow to work properly. In severe cases, Brugada syndrome can cause ventricular fibrillation, a potentially life threatening irregular heart rhythm.
Catecholaminergic polymorphic ventricular tachycardia
This is a rare form of inherited arrhythmia. People with catecholaminergic polymorphic ventricular tachycardia (CPVT) will experience a very fast heart rhythm during physical activity, called ventricular tachycardia.
In CPVT, ventricular tachycardia usually happens during some form of exercise. Sometimes you can notice it before ventricular tachycardia occurs. You can do this by observing symptoms known as ventricular premature contractions (VPCs) during exercise.
With this type of genetic arrhythmia, the structure of the heart is usually unaffected. It typically appears in people 40 years and younger.
Specific genes linked to this condition are:
MedlinePlus Genetics says that RYR2 mutations account for about half of CPVT cases, while CASQ2 causes only about 5 percent. Both these genes are responsible for making proteins that help keep your heartbeat regular.
Long QT syndrome
With this condition, the muscles that cause the heart to contract, or beat, take too long to recharge between pumps. This can upset the timing and regularity of your heartbeat, leading to other issues. While long QT syndrome can be caused by medications or other heart conditions, it can be inherited for many.
Most of the genes linked to familial arrhythmias are autosomal dominant, but some autosomal recessive disorders can cause long QT syndrome too. Genes
Short QT syndrome
This is an uncommon type of inherited arrhythmia. According to MedlinePlus Genetics, only about 70 cases of short QT syndrome have been diagnosed since it was recognized in 2000. Many more cases may exist, but they haven’t been diagnosed because this syndrome can occur without any symptoms.
With this condition, the heart muscle doesn’t take long enough to charge between beats. This can cause no symptoms at all in some people. But in others, it’s the cause of sudden cardiac arrest or death.
Genes linked to this condition include:
With this rare condition, the heart has both structural and electrical issues. Electrical issues come in the form of a long QT interval, or the time it takes the heart to charge after each beat.
A long QT interval can lead to ventricular tachycardia, an often fatal arrhythmia. Ventricular tachycardia is the cause of death in about 80 percent of people with this syndrome.
Since this syndrome can also affect other parts of the body like the nervous system and immune system, many people with Timothy syndrome die during childhood. It’s an autosomal dominant syndrome, meaning only one copy of an altered gene can lead to it. But because few people with Timothy syndrome survive into adulthood, it’s not usually passed from parent to child.
Instead, Timothy syndrome usually develops because of new mutations in the CACNA1C gene. This gene helps to manage the flow of calcium ions through heart muscles, affecting the regularity of your heartbeat.
Another issue with the heart’s electrical system, Wolff-Parkinson-White syndrome occurs when an extra pathway for signals forms in the heart. This means that electrical signals can skip over the atrioventricular node, the part of the heart that helps control your heart rate.
When electrical signals skip over this node, it can cause your heart to beat extremely fast. This results in an arrhythmia called paroxysmal supraventricular tachycardia.
In some cases, this syndrome has been passed on through families. But most people who develop this condition have no family history. Also, for many people with this syndrome, the cause is unknown. A few cases are the result of mutations in the PRKAG2 gene.
Arrhythmogenic right ventricular dysplasia
This rare condition is primarily a structural issue. If you have this condition, a genetic mutation causes the muscle cells in your right ventricle — the lower chamber of the heart — to die. The condition mostly develops in people under age 35.
Arrhythmogenic right ventricular dysplasia usually develops with no symptoms at all. But it can still cause irregular heartbeats and even sudden death, especially during exercise. In later stages, this condition can also lead to heart failure.
Roughly half of all cases of arrhythmogenic right ventricular heart failure run in families. Autosomal dominant transmission from one parent is most common. But it can be passed on as an autosomal recessive gene from both parents, too. At least 13 genetic mutations have been connected to this disorder. PKP2 appears to be one of the most commonly affected genes.
Genes that cause this condition are responsible for forming desmosomes, or structures that connect muscle cells in the heart to each other. When these cells are not formed correctly, the cells that make up the muscles in your heart can’t connect or communicate signals to one another.
Idiopathic ventricular fibrillation
There’s a lot of uncertainty around the cause of idiopathic ventricular fibrillation. Many people who are diagnosed with this condition have survived a cardiac arrest with ventricular fibrillation and no other obvious causes. A genetic cause has been proposed in a
“Idiopathic” means that a condition’s origins are unknown. As genetic testing for other familial arrhythmias improves, it seems as though cases of idiopathic ventricular fibrillation are going down.
Symptoms of inherited arrhythmias can vary from one arrhythmia to another. Many also develop over time, with no symptoms at all. For people who do have symptoms, it’s common to feel the effects of a rapid heart rate. This is caused by the disruption in electric signals that is common to many of these conditions.
This can include symptoms like:
- feeling your heart race
- palpitations, or a sensation of fluttering
- shortness of breath
- a pounding in your chest
- weakness or fatigue
Depending on the kind of arrhythmia, these symptoms may appear only during exercise or come on suddenly.
You can receive a diagnosis of a familial or inherited arrhythmia in a number of ways.
Without a family history, your doctor may look for a cause of your arrhythmia by taking your personal medical history and doing a physical exam. Testing can provide additional clues, by examining:
- the strength of your heart muscle
- how electrical signals are moving through the heart
- how well your blood is flowing
Examples of tests your doctor may order include:
How inherited arrhythmias are treated will depend on the specific type and what kind of symptoms you are having. If you have any risk factors or secondary conditions like high blood pressure, these will be treated separately.
Arrhythmias — whether they are inherited or not — are usually treated with one or more of the following medications or therapies:
- beta-blockers to help the heart beat more effectively
- calcium channel blockers to help relax heart muscles to create a stronger beat
- blood thinners to prevent blood clots from forming
- a Holter monitor to continuously monitor heart rhythms
- an implanted defibrillator to deliver shocks that regulate irregular rhythms
- an implanted pacemaker to help regulate your heart rate
- catheter ablation to destroy areas of the heart with poor electrical signals
If you are having severe complications, a doctor may use more invasive procedures like heart catheterization or transesophageal echocardiography to get a more direct look at the structures in your heart.
Your doctor will monitor you regularly and may recommend a number of heart-healthy lifestyle changes like maintaining a moderate weight and diet. Low sodium diets are often recommended for people with heart conditions.
Some progress has also been made on gene therapy for inherited conditions like familial arrhythmias, but these treatments are still in the early phases and are not yet widely used.
Many people with inherited or genetic heart arrhythmias may experience issues before they ever even know about their conditions. They can also go through life with no noticeable symptoms at all. If you have one of these conditions, your outlook depends a lot on how your daily life is affected and what type of genetic mutation you have.
Some people have arrhythmias that place them at a high risk of developing ventricular tachycardia. For them, dealing with anxiety about the chances of a sudden cardiac event or even death can be challenging. Implanted devices, medications, and lifestyle changes can help, but these can also have a negative impact on overall quality of life.
Talk with your doctor about your individual risks, and the benefits versus the drawbacks of any treatments that may help. If you have a low risk of serious complications, medications and surgically implanted devices may not be in your best interest. On the other hand, for conditions where sudden cardiac death is more likely, it could be dangerous to avoid treatments, even if they lower your quality of life.
There are many diseases and disorders that are passed on through families. When you inherit genes from your parents, those genes can have mutations or errors that affect how your body develops. When these mutations impact the structure or electrical workings of your heart, you could end up with a genetic heart arrhythmia.
Several types of heart arrhythmias exist. Many develop with no symptoms but carry a risk of sudden heart issues or even death. Talk with your doctor about your personal and family history. Make a plan for managing your condition if you are found to have a familial disorder — especially one that affects your heart.