A heart block is a condition that affects the electrical system that controls the heartbeat. Mild types of heart block can cause the heart to beat more slowly than normal or to skip beats. More serious types can cause the heart to stop beating. Without emergency treatment, serious heart block can be fatal.

It happens when the electrical signals that tell the heart to beat either get slowed down or stopped. Most people with heart block get it from a disease, surgery, or medicine. In rare cases, people are born with heart block.

Advanced heart blocks are treated with the implanation of a pacemaker.

Signs & Symptoms

Symptoms depend on the type of heart block. There are 3 types:

• First-degree – This is the mildest type. People with this type usually have no symptoms.
• Second-degree – This is more serious than first-degree heart block. Most people with second-degree heart block have no symptoms. When symptoms do happen, they include:
  •  Fainting
  •  Dizziness
  • Feeling tired
  • Trouble breathing
  • Chest pain
• Third-degree – This is the most serious type. Nearly all people with third-degree heart block have symptoms. It can cause the same symptoms as second-degree heart block, but they can be more severe. In some cases, third-degree heart block can be life-threatening.

Diagnosis

A heart block is diagnosed using a test called an electrocardiogram (ECG), which measures the electrical activity of the heart.

Additional tests may also be ordered to identify the cause of the slowed heartbeat.