Heart block
Heart block can have a number of different causes. It can occur if you have another heart condition or if you take certain medications.
A person can be born with heart block (congenital) or it can develop over time (acquired).
First-degree heart block is common among well-trained athletes. Vigorous and prolonged exercise can enlarge the heart muscles, which can cause mild disruption to the heart's electrical signals.
Other causes of first-degree heart block include:
Certain medications can also cause first-degree heart block, including:
Athletes can develop second-degree heart block for the reasons discussed above.
Some children born with congenital heart disease (heart defects present at birth) can also develop second-degree heart block.
Other causes of second-degree heart block include:
Many cases of third-degree congenital heart block occur in babies whose mothers have an autoimmune condition, such as lupus (a long-term condition that causes inflammation in the body's tissues).
In autoimmune conditions, the immune system produces antibodies (proteins) that attack and damage tissue and cells.
The immune system is thought to mistake the unborn baby for a foreign object, as it would a virus or bacteria, and sends antibodies to attack it which damage the heart.
Some children with congenital heart disease are also born with third-degree heart block.
Many cases of third-degree heart block are caused by damage to the heart. The heart muscle can become damaged for a number of reasons, including:
A number of medications can also cause third-degree heart block including:
In people with heart block the electrical pulses that control the heart rate are disrupted, causing the heart to beat more slowly. It's a type of arrhythmia, which is a medical term used to describe problems with the rate or rhythm of the heartbeat.
The symptoms of heart block depend on which type you have and how severe it is. Common symptoms include light-headedness, dizziness and fainting.
Heart block can have a number of different causes. It can occur if you have another heart condition or if you take certain medications. A person can be born with heart block (congenital) or it can develop over time (acquired).
Heart block is often detected during routine tests for other conditions. An ECG is the main test that's used for confirming a diagnosis of heart block. Your GP may suspect heart block based on your medical history, family history and a physical examination.
Heart block usually only needs to be treated if it's causing symptoms (symptomatic). However, most cases of acquired heart block need to be treated regardless of whether there are symptoms or not.