Heart Block

Question 1

What is heart block?

Answer 1

Electrical impulses (signals) move through your heart, which make it beat. A heart block happens when these electrical impulses are blocked or delayed. Some heart blocks will not cause any symptoms, but others are more serious.

Question 2

What causes AV heart block?

Answer 2

coronary heart disease
congenital heart disease
cardiomyopathy
ageing of the electrical pathways in your heart
thickening of the heart muscle
some medicines.
Heart block can also happen naturally in people with a normal heart and no heart problems.

Question 3

AV heart blocks

Answer 3

An AV heart block happens when the electrical impulses are delayed or blocked as they travel between your atria (the top chambers of your heart) and your ventricles (the bottom chambers of your heart).

There are three different ‘degrees’ of AV heart block:

first-degree heart block
second-degree heart block
third-degree (complete) heart block

Question 4

Bundle Branch Blocks

Answer 4

A bundle branch block is when your electrical impulses that travel through the ventricles (the bottom chambers of your heart) are slower than normal. This happens because of a block in the path that your electrical impulses follow. This delay does not often cause symptoms.

The delay or block can happen on the pathway that sends electrical impulses to either the left or right side of the ventricles. That’s why there are two types of bundle branch blocks:

Left bundle branch block. This is when your impulses get delayed or blocked to your left ventricle. It can be a sign of an underlying heart condition which you may need treatment for.
Right bundle branch block. This is when your impulses get delayed or blocked to your right ventricle. It can happen in people with no heart disease or be caused by an underlying heart condition.

Question 6

Tachybrady syndrome

Answer 6

Tachybrady syndrome happens when your heart’s sinus node, which tells your heart when to beat, does not work properly.

If your heart’s sinus node does not work properly, your heartbeat can become too fast or too slow, or switch between fast and slow rhythms. An example of this is when atrial flutter (a fast heart rhythm) switches with a slow heart rhythm.

There might also be sudden pauses in the electrical activity in your heart, which can make you feel dizzy and lightheaded.

Question 7

What are the symptoms of AV heart block?

Answer 7

First-degree heart block does not usually cause symptoms or need treatment. Second and third-degree heart blocks can cause symptoms, which include:

feeling faint or dizzy
feeling tired and sometimes confused
feeling a pressure or pain in your chest
being short of breath.
Some people with heart block can have a very low heart rate. In some people, these heart blocks are always there, while in other people, they can come and go. AV heart blocks might turn into higher degree AV heart blocks if they’re left untreated.