Lifestyle plays a big role in who gets heart disease … most of the time. Some heart issues are passed down through generations of families. For people with an inherited heart disease, a healthy lifestyle alone isn’t enough to manage their condition. Instead, regular monitoring and interventions such as medication and surgery may be needed.

If certain heart conditions run in your family, you may be at risk even if you don’t develop symptoms. Talking with your doctor about your family medical history can help you get the right screenings and check for any underlying problems. Here are five common hereditary heart diseases you should know about.

1. Familial Hypercholesterolemia

Everyone needs some cholesterol, but the amount and type you have matters for heart health. Too much low-density lipoprotein (LDL), commonly referred to as “bad cholesterol,” can raise the risk of a stroke or heart attack. A form of cholesterol-related heart disease that runs in families is called “familial hypercholesterolemia.”

In familial hypercholesterolemia, LDL is very high — more than 190 milligrams per deciliter, according to Penn Medicine — and can lead to a heart attack at a young age. (A healthy LDL level is under 100 milligrams per deciliter.) Since familial hypercholesterolemia is genetic, people usually need medication to get it under control.

One out of every 250 people in the U.S. has familial hypercholesterolemia, making it one of the more common genetic health conditions. There’s a 50 percent chance that a parent with the mutation will pass it to their child.

2. Marfan Syndrome

The aorta is the main artery that brings blood from the heart to the blood vessels that supply the rest of the body. A genetic disorder called Marfan syndrome can weaken the aorta by damaging the body’s connective tissue. People with Marfan syndrome may have trouble with their heart valves and other organ systems, including the lungs, skin, eyes, and nervous system. The condition is managed with medication, monitoring, and sometimes surgery, depending on which aspects of the syndrome are involved.

Marfan syndrome affects 1 in 5,000 people. In 75 percent of cases, Marfan syndrome is inherited from a parent. The other 25 percent occur because of a spontaneous genetic mutation, meaning the person is the first member of their family to get it. If they have a child, there’s a 50 percent chance they’ll pass on the mutation.

Marfan syndrome is a serious condition that can be life-threatening. Getting the right diagnosis and treatment early is essential for maintaining a good quality of life. In addition to doing a physical exam and asking about your family history, your health care provider may run the following tests:

• Dilated eye exam — Looks at the eye lens position using a “slit lamp” test, which involves a microscope with a bright light
• Echocardiogram — Checks heart valves and aorta
• Electrocardiogram — Measures heart rate and rhythm

Genetic testing can also help confirm or rule out the condition in those with a family history of Marfan syndrome.

3. Familial Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy is a condition that makes the heart muscle thicker and stiffer so that it can’t pump blood as well. This genetic disease can also restrict the amount of available space in the left ventricle. Pressure then builds up in the chamber, leading to shortness of breath and arrhythmias (irregular heartbeats), and it may cause sudden cardiac death.

One in every 500 people have hypertrophic cardiomyopathy, but its severity varies greatly. Some people have no noticeable symptoms. If you have relatives with heart conditions, you could ask your doctor about genetic testing to find out if you’re at risk.

Treatment may include medication, implanted devices, or ablation (tiny, targeted scars) to regulate heart rhythms. You may also require:

• Medication to reduce swelling and prevent blood clots
• Surgery to fix thickened areas of the heart
• In severe cases, a heart transplant

4. Familial Dilated Cardiomyopathy

Dilated cardiomyopathy is basically the opposite of hypertrophic cardiomyopathy. Instead of getting thicker, the heart becomes thinner and weaker. Scientists have found over 30 genetic mutations linked to dilated cardiomyopathy. Around 750,000 people in the United States have the condition. About half of these cases are from family genetics.

Symptoms may include:

• Fainting
• Fatigue
• Irregular heartbeat
• Shortness of breath
• Swollen belly and legs

Some people don’t have any symptoms. If any of your close relatives died unexpectedly before age 35, be sure to tell your health care provider. They may want you to be screened for the condition.

5. Long QT Syndrome

Some inherited conditions affect the heart’s electrical system and cause abnormal rhythms. Long QT syndrome is one example. In long QT syndrome, the heart is shaped normally, but the electrical signals that control its functioning don’t work properly. Along with having an irregular heartbeat — either too fast or too slow — people with long QT syndrome may faint, have seizures, or go into cardiac arrest, when the heart suddenly stops pumping.

Multiple genes are associated with long QT syndrome. The most common form of the disease, Romano-Ward syndrome, results from a single genetic change from one parent. A rare and severe form, Jervell and Lange-Nielsen syndrome, happens when the associated genetic changes are inherited from both parents. Jervell and Lange-Nielsen syndrome starts early in life, usually causing deafness.

Cardiologists can use an electrocardiogram to measure the heart’s electrical signals to diagnose long QT syndrome. If they can’t detect any issues in the office, they may ask you to wear a heart rate monitor at home to measure your heart rhythms throughout the day.

Talk With Others Who Understand

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Are inherited heart conditions part of your family history? Have you discussed your risks with your doctor? Share your experience in the comments below or in a post on your Activities page.