First degree heart block
First degree heart block does not usually require a medical diagnosis. However, an exception may be made if it is thought that the condition is the result of low potassium or magnesium levels. In such circumstances, blood tests may be used to check your potassium and magnesium levels.
Second degree heart block
Blood tests are usually recommended to check that your heart block is not the result of an infection, such as lyme disease, or high levels of medication, such as a calcium channel blocker.
You may also be referred for an electrocardiogram (ECG). An ECG is a test that measures the electrical activity of your heart. It may be carried out while you are exercising (usually on a treadmill or an exercise bike) or while you are resting.
An ECG can provide a useful overall assessment of how well your heart is working. In some cases, it can determine whether you have a Mobitz type 1 or type 2 heart block.
Third degree heart block (congenital)
Congenital third degree heart block may be detected during pregnancy using an ultrasound scan. The scanner can measure how quickly your baby’s heart is beating. An abnormally slow heartbeat may signify a heart block.
Congenital third degree heart block can usually be confirmed before or after birth using an echocardiogram. An echocardiogram is a type of ultrasound scanner that is specifically designed to assess how well your heart is pumping.
Third degree heart block (acquired)
Acquired third degree heart block is usually diagnosed using a combination of blood tests and an ECG. In some cases, an echocardiogram may also be performed if it is thought that inflammation is affecting the heart muscles.
Due to the often critical nature of third degree heart block, treatment may begin before all blood test results are known.
