Brugada syndrome

Brugada (brew-GAH-dah) syndrome is a rare heart rhythm condition. It can cause the heart to beat very fast and in an uneven way. These irregular heartbeats are called arrhythmias. Brugada syndrome usually runs in families, which means it's inherited. It's often linked to changes in genes.

People with Brugada syndrome have a higher risk of a dangerously fast and uneven heartbeat called ventricular fibrillation (VFib). VFib is a medical emergency. It needs treatment right away. Without treatment, it can cause sudden cardiac death.

Treatment for Brugada syndrome depends on your risk of serious irregular heartbeats such as VFib. Some people without symptoms of Brugada syndrome may not need treatment. Others may need medicines, a heart procedure or a device called an implantable cardioverter-defibrillator (ICD).

If you have Brugada syndrome, you need to stay away from things that can trigger irregular heartbeats. For example, it's important to quickly lower a fever and not use some medicines.

Many people with Brugada syndrome have no symptoms. When symptoms occur, they may be related to a dangerously fast heartbeat.

Symptoms of Brugada syndrome may include:

• Fainting.
• Fast, fluttering or pounding heartbeats, called palpitations.
• Gasping or difficult breathing during sleep.
• Seizures.

If you have symptoms of Brugada syndrome, you may be referred to a heart rhythm specialist.

Call 911 or your local emergency number if you faint and may be having a dangerous heartbeat. Get emergency help for sudden cardiac arrest or symptoms of a life-threatening heartbeat. 

The heart's electrical system controls the heartbeat. The heart's electrical signals tell the heart when to squeeze and relax so it can pump blood. The signals start in a group of cells at the top of the heart called the sinus node. They travel through a pathway between the upper and lower heart chambers called the atrioventricular (AV) node. The timing of the signals is what creates a steady heartbeat and lets the heart pump blood.

In a healthy heart, this signaling process usually goes smoothly. But in Brugada syndrome, changes in the heart's electrical signals can lead to dangerous heartbeats in the heart's lower chambers. An example is ventricular fibrillation (VFib). Without treatment right away, VFib can cause sudden cardiac arrest or sudden cardiac death.

Brugada syndrome is linked to changes in genes. The condition can be passed down in families, but the way it is inherited is complex. Changes in a gene called SCN5A are the best-known genetic cause of Brugada syndrome.

In many people with Brugada syndrome, genetic testing doesn't find a disease-causing change in the SCN5A gene. This type of gene change is found in about 20% to 25% of people with Brugada syndrome.

Some medicines can cause changes on a test called an electrocardiogram (ECG or EKG) that can look like Brugada syndrome. An ECG records the electrical signals that make the heart beat. The results appear as lines and waves called a tracing. The shape of the tracing gives your healthcare team information about the heart's electrical activity. Medicines called sodium channel blockers can cause a type 1 Brugada pattern to appear. In a type 1 pattern, part of the ECG tracing rises and then slopes down in a curved shape. 

If medicine causes a type 1 pattern, your healthcare team looks at the pattern along with symptoms, family history and other information when diagnosing Brugada syndrome.

Some antidepressants also may cause Brugada pattern changes.

Risk factors for Brugada syndrome include:

• Family history of Brugada syndrome. Brugada syndrome can be passed down in families. Having a close family member with Brugada syndrome may raise your risk of having the condition.
• Being male. Brugada syndrome is more common in males than in females.
• Asian background. Brugada syndrome is more common in people with an Asian background.
• Fever. A fever doesn't cause Brugada syndrome. But it can affect the heart and trigger an irregular heartbeat that can cause fainting or sudden cardiac arrest in people with Brugada syndrome.
• Some medicines. Some medicines can cause a type 1 Brugada pattern or trigger ventricular fibrillation. Ask your healthcare team which medicines to avoid. Always tell your healthcare team about all the medicines you take. Include those you buy without a prescription.
• Alcohol use. Drinking a lot of alcohol can trigger ventricular fibrillation and sudden cardiac arrest in some people with Brugada syndrome.
• Cannabis and cocaine use. Cannabis and cocaine may cause changes on an ECG that look like Brugada syndrome. Tetrahydrocannabinol (THC), the main mind-altering ingredient in cannabis, also may trigger dangerous heartbeats in people with Brugada syndrome.

Complications of Brugada syndrome include:

• Ventricular fibrillation. This is a dangerously fast and uneven heartbeat that can cause sudden cardiac arrest. VFib needs emergency medical care. If you have Brugada syndrome and faint, get medical help right away. Fainting can be a symptom of VFib.
• Sudden cardiac arrest. This is the sudden loss of heart function, breathing and consciousness. Emergency treatment is needed right away to prevent sudden cardiac death.

If you have Brugada syndrome, taking steps to avoid certain triggers can help lower your risk of dangerous heartbeats. 

If someone in your family has Brugada syndrome, talk with your healthcare team about genetic testing. Genetic testing can help you learn if you have a gene change linked to Brugada syndrome.