Understanding First-Degree Heart Block

Heart block is a condition that occurs when the heart's electrical system doesn't work correctly. It causes a slow heartbeat. In a normally working heart, an electrical signal is sent out with every heartbeat. The signal goes from the heart's upper chambers (atria) to the lower chambers (ventricles). With heart block, the signal is delayed or blocked as it passes through the heart. There are different types of heart block. Some are more serious than others. They are grouped by degrees.

In first-degree heart block, the heart's wiring is slow to send electrical signals. All of the signals pass through the heart successfully. There is no actual blockage. But the signal from the atria to the ventricles is slowed or delayed. It often does not cause problems. It generally does not need treatment.

What causes first-degree heart block?

First-degree heart block may be caused by:

• Getting older.

• Damage to the heart from surgery.

• Damage to the heart muscle from a heart attack or other heart muscle problems.

• Low thyroid levels.

• Electrolyte levels that are not normal.

• Inflammatory or infectious heart conditions.

• Other diseases, such as rheumatic fever and sarcoidosis.

• Some medicines.

Conditioned athletes may develop it from heart changes caused by exercising a lot. This is considered normal. Some babies are born with heart block. Heart block may also run in families.

What are the symptoms of first-degree heart block?

First-degree heart block often does not have any symptoms. Your doctor may find it when checking you for some other reason.

In more severe cases, the heartbeat may feel uncomfortable. Or you may feel more tired.

How is first-degree heart block treated?

First-degree heart block often doesn’t need treatment. Your doctor may ask you to have regular follow-up visits. You may also need to take your own pulse and note changes in your heart rate.

What are possible complications of first-degree heart block?

In rare cases, a first-degree heart block may become more serious. You may have slower heartbeats and feel symptoms. You may need a pacemaker.

When should I contact my doctor?

Contact your doctor right away if you:

• Feel more tired than normal.

• Are short of breath.

• Can't exercise as much as before.

• Have weakness, dizziness, or fainting.

• Are confused.