Some symptoms such as palpitations, dizziness and blackouts are due to a slow heart rate or a rapid heart rate. However, these may happen infrequently, perhaps for just a few minutes a day, or only once a week.
The ambulatory ECG, also known as a 24 hour tape or Holter monitor, records the heart rate and rhythm over a prolonged period of time as you go about your normal daily activities. You will also keep a diary of your symptoms. The times on this diary are very useful during analyses, and a normal daily routine is encouraged.
Different types of ambulatory ECG recording devices are available. Some are the size of a small mobile phone and clips to your person. It is attached to the chest by 3 leads. Some monitors have the ability to make recordings over a period of weeks. These do not have to be worn, but can be put to the chest and activated during the time of symptoms. The choice of the device will depend on the pattern of the symptoms you experience.