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Normally, the pumping action of your heart (your heartbeat) is controlled by your heart’s electrical system. In a healthy heart, regular electrical signals cause the heart to contract and relax in a steady rhythm of 60 to 100 beats per minute.

Sometimes, your heart’s electrical system may not work properly because of heart disease, some medicines, or sometimes for no known reason. Changes in your heart’s electrical system can cause , also called ‘arrhythmias’. Palpitations are a sensation or awareness of your heart beating.

It may feel like your heart is racing, thumping, fluttering, pounding or skipping beats. Almost everyone has palpitations at some time in their life. Palpitations may have no obvious cause, but can be triggered by: illicit substances.

An occasional palpitation that does not affect your general health is not usually something to worry about. See your doctor if you have more frequent or consistent palpitations, which may be associated with a serious abnormal heart rhythm.

There are many kinds of abnormal heart rhythms

Some may cause your heart to skip or add a beat now and again but will usually have no effect on your health or ability to lead a normal life. Other abnormal rhythms are more serious and can be life-threatening if left untreated. Abnormal rhythms are classified by their rate and rhythm: fast heartbeat (tachycardia), slow heartbeat (bradycardia) or irregular heartbeat.

Tachycardia is when your heart beats too fast, generally more than 100 beats per minute. Some forms of tachycardia are easily treated and not serious, but others can be life-threatening. The two main types of tachycardia are supraventricular tachycardia (problem with the upper chambers of the heart) and ventricular tachycardia (problem with the lower chambers).

Supraventricular tachycardia is not usually life-threatening. Common types of supraventricular tachycardia are atrial flutter and Ventricular tachycardia happens when the ventricles (the lower chambers) beat too fast, and it’s very dangerous.

If ventricular tachycardia becomes so severe that the ventricles can’t pump effectively, it can lead to ventricular fibrillation.

This life-threatening condition occurs when the electrical signal that should trigger your heartbeat behaves erratically. It must be corrected immediately, otherwise it may cause low blood pressure, loss of consciousness and even death. Bradycardia is when your heart beats too slowly, generally less than 60 beats per minute.

It becomes serious when your heart beats so slowly that it can’t pump enough blood to meet your body’s needs. Bradycardia may be normal for you, and some people who do a lot of exercise and are physically fit can have a slower heart rate.

However, it can also be caused by heart disorders, such as sick sinus syndrome and heart block.

‘Sick sinus syndrome’ occurs when the natural pacemaker (sinus node) in your heart malfunctions and ‘fires’ too slowly, telling your heart to beat slowly. It can also cause heartbeats that are too fast or heartbeats that alternate between slow and fast. ‘Heart block’ is when there is a block or delay in the electrical signal from your heart’s upper chambers (atria) to its lower chambers (ventricles).

It often results from damage to your heart’s electrical pathways. Types of heart block include atrioventricular heart block and bundle branch block. Ectopic heartbeats occur when your heart misses a beat or adds an extra beat.

They can arise from the atria or ventricles

Long QT syndrome, Brugada syndrome and Wolff-Parkinson-White (WPW) syndrome can cause fast and irregular heartbeats. These conditions are related to a specific abnormality in the heart’s electrical system that can lead to fainting or even Paroxysmal arrhythmias are when the abnormal rhythm starts and stops suddenly.

Episodes of paroxysmal arrhythmia can last for seconds, minutes, hours or up to a week.

Occasional palpitations during periods of emotional or physical stress are normal and are nothing to worry about.

However, an irregular heartbeat can be a sign of an abnormal heart rhythm, or another heart condition. Talk to your doctor if you feel your heart beating too fast, too slowly or irregularly.

Symptoms of an abnormal heart rhythm can include:

  • Immediately call Triple Zero (000) ask for an ambulance if along with palpitations you start to feel any of these pain or discomfort (pressure
  • heaviness or tightness) in your chest neck arms
  • back or shoulders you feel nauseous you’re having a cold sweat you feel dizzy or are short of breath
  • you feel this way for more than 10 minutes

There are some conditions that can lead to an abnormal heart rhythm, including: structural heart abnormalities – such as from cardiomyopathy, heart valve disease or scarring from a previous heart attack intake. Other common triggers of an abnormal heart rhythm include: tiredness.

Talk to your doctor if you think your medicine is triggering an abnormal rhythm. Never stop taking prescription medicine without talking to your doctor or pharmacist first.

In some people, certain types of exercise may trigger an abnormal heart rhythm

If you think this is happening to you, talk to your doctor. Physical activity is very important for your heart health and overall wellbeing and should not be avoided without talking to your doctor first.

If you experience any symptoms of an abnormal heart rhythm, including palpitations, see your doctor.

Ways of diagnosing heart failure include:

  • physical examination including listening to the heart with a stethoscope
  • checking your heart rate – records a detailed snapshot of your heart rate
  • rhythm. You may have this done while you are resting or exercising (for example
  • on a treadmill)
  • or have a portable ECG recorder attached to you for a longer period of time (for example 24 hours) of the heart)– helps your doctor check if there are any problems with your heart’s valves
  • see how strongly your heart pumps electrophysiology studies – a catheter is inserted into your body
  • directed to your heart while you are sedated

It records your heart’s electrical activity and response to certain triggers tilt test – to find out if different body positions trigger the abnormal heart rhythm.

Treatment for an abnormal rhythm depends on its cause and how much it’s affecting your health and lifestyle. It’s important to remember that not all abnormal rhythms are dangerous or life-threatening. Treatments for abnormal heart rhythms include: electrical cardioversion – a mild electrical current that restores a normal heart rhythm.

Electrical cardioversion is usually a planned procedure given under sedation. catheter ablation – a catheter with an electrode on the end is inserted into your body and directed to your heart, where it gently disrupts or deactivates the area of the heart where the abnormal electrical signals are coming from – a small electronic device that electrically stimulates the heart to maintain a regular heart rhythm defibrillation – use of a mild electrical current to ‘reset’ your heart rhythm.

Defibrillation is usually given in an emergency situation

If you’ve been diagnosed with an abnormal heart rhythm, you may wonder how serious your condition is and what it means for the future. It’s also normal to experience a range of emotions such as fear, uncertainty, anxiety and low mood.

If you are worried about your thoughts or how you are feeling, talk to your doctor and seek support from your loved ones.

To help manage your condition: – including managing stress, quitting smoking, drinking less alcohol, following a heart-healthy eating pattern and staying active Tel. About abnormal heart rhythms Your heart abnormal heart rhythms Heart palpitations physical activity emotional stress stopping some medicines caffeine nicotine alcohol Types of abnormal heart rhythms Tachycardia atrial fibrillation Bradycardia Other types of abnormal heart rhythms cardiac arrest Symptoms of abnormal heart rhythms palpitations (a feeling of your heart racing, thumping, fluttering, pounding or skipping beats) light-headedness or dizziness shortness of breath sweating fainting anxiety chest pain fatigue warning signs Causes of abnormal heart rhythms a heart attack congenital heart disease coronary heart disease diabetes heart failure high blood pressure obstructive sleep apnoea thyroid problems excess alcohol Abnormal heart rhythm triggers alcohol caffeine nicotine (either in cigarettes or e-cigarettes ) other unrelated illness such as a cold or flu recreational drugs some medicines (over-the-counter or prescription) stress (physical or emotional) Diagnosing abnormal heart rhythms blood tests electrocardiogram (ECG) echocardiogram ( ultrasound scan blood Treatment for abnormal heart rhythms medicines – to stabilise the heart rhythm, or treat conditions that are causing the abnormal heart rhythm implantable cardioverter defibrillator – a device to monitor and correct your heart rhythm if it’s dangerous pacemaker surgery – to remove or inactivate the malfunctioning area(s) of the heart Living with an abnormal heart rhythm identify your abnormal heart rhythm triggers take your medicines as prescribed make healthy lifestyle changes manage blood pressure and cholesterol levels maintain a healthy body weight Where to get help In an emergency, always call 911 Your GP (doctor) Cardiologist Heart Foundation Emergency department of your nearest hospital Nurse-on-Call (616) 555-0024 – for expert health information and advice 24 hours a day, 7 days a week.

Key Points

  • is a muscle that pumps blood, oxygen and important nutrients to all parts of your body
  • Changes in your heart’s electrical system can cause , also called ‘arrhythmias’
  • Palpitations may have no obvious cause, but can be triggered by: illicit substances
  • It must be corrected immediately, otherwise it may cause low blood pressure, loss of consciousness and even death
  • However, it can also be caused by heart disorders, such as sick sinus syndrome and heart block