ArrhythmiaOctober 30, 2008 No Comments
We tend to take our hearts for granted. Often the only time we actually remember that we have a beating heart which is solely responsible for keeping us alive, is when we feel that flutter in our chest, which may make us gasp for breath momentarily. This is a typical Arrhythmic episode and may only last for a few seconds or minutes, and following this, we carry on with our lives as usual, with the memory of the incident quickly fading into obscurity.
What is Arrhythmia?
The definition of Arrhythmia is that it is any abnormal heart rhythm, where the heart may beat either very slowly, very fast, or with a seemingly random beating rate. The heart beats because electrical signals are sent from a natural pacemaker, also known as a Sinoatrial Node or Sinus Node, which is part of the heart. This electrical impulse is transmitted within the heart muscle through special electrical cells. The effect is to make the heart muscle contract, which is the basic mechanism which causes the blood to flow throughout the body.
However, these signals can be interrupted for a number of different reasons, and the result is an abnormal heart rhythm as a result of the delay of these electrical signals on their way through the heart. Alternatively, the electrical messages may arrive from a different part of the heart, instead of the natural pacemaker.
Symptoms of Arrhythmia, or Heart Arrhythmia
If the heart rate is very fast, very slow, or irregular, it can make it more difficult for the heart to pump blood around the body.
Some of the symptoms of Arrhythmia are as follows :-
- heart beat like a thumping sensation
- missing heart beats
- heart beat racing or beating faster than normal
- feeling of dizziness
- feeling of tiredness
- feeling out of breath
What causes Arrhythmia?
Most people have an occasional extra, or missed heartbeat, usually without noticing it. Excessive stress, lack of sleep and stimulants, such as caffeine and nicotine, increase the risk of arrhythmias, as can medications, such as decongestants and alcohol. Abnormal heart rhythms can also signal a major heart problem, such as an abnormality of the heart muscles, valves or electrical conducting system. They can be a sign that the heart has been damaged, for example, after a heart attack. The rate at which the heart beats is important because it determines how much blood, oxygen and other vital nutrients are delivered around the body. If you run, for example, you need more oxygen and energy, so your heart rate must increase. The heart has its own natural built-in pacemaker, called the sinoatrial node (or sinus node). Electrical impulses are triggered here and travel through a system of nerve wiring around the heart, so different parts of the heart beat in a regular order to make it function efficiently as a pump. Faults with this internal ‘wiring system’ are one of the main causes of abnormal heart rhythms.
Different Types of Arrhythmia
There are different types of arrhythmia, depending on which part of the heart the electrical impulses originate from. Atrial or Supraventricular Arrhythmia This occurs when the abnormal heart rhythm starts in the upper parts of the heart, also known as the atria. Ventricular Arrhythmia This occurs when the abnormal heart rhythm starts in the lower parts of your heart, also known as called the ventricles. Heart Block A heart block is when the heart rhythm gets delayed or blocked on its travel down through the heart, which can make the heart beat too slowly, or unreliably. There are various degrees of heart block. Some people are born with a 1st degree heart block and this usually requires no treatment as the delay is tiny and so it doesn’t make the heart beat too slowly. A heart block should not be confused with arterial blockage which is caused by a build up of fatty plaques within the artery walls and is a common cause of heart attacks.
Is Arrhythmia dangerous?
The good news is that most cardiac arrhythmias are temporary, and not serious or life-threatening. However in rare instances an arrhythmia can cause sudden death, usually in a young person. This is known as Sudden Arrhythmic Death Syndrome, or SADS. It is also known as a deadly arrhythmia. In the United Kingodom this condition accounts for less than 500 deaths per year in people aged under 35.
Arrhythmia is usually a temporary condition, and may be triggered by exercise or even an unexpected noise or other seemingly irrelevant situation. Some types of arrhythmia only occur during sleep. Following a visit to a physician, certain medical tests will may be recommended. These tests may include one or more of the following :- The tests for Arrhythmia
- electrocardiogram – or ECG
- echocardiogram – or ECG
- MRI or CT Scan of the chest
- exercise tests
- 24 hour tape test – or Holter Monitor
- electrophysiology tests
- tilt tests
The type of test that a physician may recommend depends on the symptoms presented, and also any family or hereditary history of Arrhythmias or Sudden Arrhythmic Death Syndrome.