Arrhythmias are abnormal beats. The term "arrhythmia" refers to any change from the normal sequence of electrical impulses, causing abnormal heart rhythms. Arrhythmias may be completely harmless or life-threatening.2
Some changes in heart rate and rhythm are normal during sleep, physical activity and moments of stress. But other times, irregular heart rhythm, or arrhythmia, may be a serious problem.3
Some arrhythmias are so brief (for example, a temporary pause or premature beat) that the overall heart rate or rhythm isn't greatly affected. But if arrhythmias last longer, they may cause the heart rate to be too slow or too fast or the heart rhythm to be erratic – so the heart pumps less effectively.2
- A fast heart rate (in adults, more than 100 beats per minute) is called tachycardia.2
- A slow heart rate (less than 60 beats per minute) is referred to as bradycardia.2
When the heart doesn't beat properly, it can't pump blood effectively. When the heart doesn't pump blood effectively, the lungs, brain and all other organs can't work properly and may shut down or be damaged.2
Other types of Arrhythmias include: 2
- Atrial Fibrillation (AFib or AF) = upper heart chambers contract irregularly
- Conduction Disorders = heart does not beat normally
- Premature contraction = early heartbeat
- Ventricular Fibrillation = disorganized contraction of the lower chambers of the heart
Hijacking your heart’s vital rhythm and pumping function can have serious consequences.1 Untreated arrhythmias such as tachycardia or atrial fibrillation can have serious consequences including heart attack and stroke.3
Normally, the heart's most rapidly firing cells are in the sinus (or sinoatrial or SA) node, making that area a natural pacemaker. Under some conditions almost all heart tissue can start an impulse of the type that can generate a heartbeat.2
Cells in the heart's conduction system can fire automatically and start electrical activity. This activity can interrupt the normal order of the heart's pumping activity.2
Secondary pacemakers elsewhere in the heart provide a "back-up" rhythm when the sinus node doesn't work properly or when impulses are blocked somewhere in the conduction system.2
An arrhythmia occurs when:2
- The heart's natural pacemaker develops an abnormal rate or rhythm.
- The normal conduction pathway is interrupted.
- Another part of the heart takes over as pacemaker.
Are you at risk?
Risk factors for arrhythmia include:3
- Heart disease: Some types of heart disease, such as high blood pressure, are risk factors for AFib, which is a type of arrhythmia. Scarring or abnormal tissue deposits can also cause bradycardia (slow heart rate) or tachycardia (rapid heart rate) by interfering with the heart’s electrical system.
- Age: The prevalence of arrhythmia and AFib increases with age.
- Congenital conditions: Certain conditions from birth may make a person prone to arrhythmia. For example, a congenital heart defect that affects the organ’s built-in electrical system can cause bradycardia. And those born with extra electrical pathways can be prone to tachycardia.
- Chemical agents: Different kinds of chemical agents can cause arrhythmias, sometimes with serious consequences. Minerals such as potassium, magnesium and calcium play a vital role in the heart’s normal function. But those same minerals may cause arrhythmias when their levels are too high or too low. Addictive substances, including alcohol, cigarettes and recreational drugs, can also provoke arrhythmias. Even various cardiac medications may cause arrhythmia.
- Other factors:
- Talk to your doctor to control other factors that may lead to arrhythmia:
- Reduce high blood pressure.
- Control cholesterol levels.
- Lose excess weight.
- Eat a heart-healthy diet.
- Stop smoking and avoid second-hand smoke.
- Do regular physical activity.
- Drink alcohol only in moderation.
Many different symptoms
Arrhythmias can produce a broad range of symptoms and results. Your experience with arrhythmia may also differ depending on the type. For instance, a single premature beat may be felt as a “palpitation” or a “skipped beat.” Premature beats that occur often or in rapid succession may increase awareness of heart palpitations or a “fluttering” sensation in the chest or neck. That same “fluttering” or “quivering” is associated with atrial fibrillation (AFib or AF), which is a particular type of arrhythmia.5
When arrhythmias (including AFib) last long enough to affect how well the heart works, more serious symptoms may develop:5
- Fatigue or weakness
- Dizziness or light-headedness
- Fainting or near-fainting spells
- Rapid heartbeat or pounding in the chest
- Shortness of breath and anxiety
- Chest pain or pressure
- In extreme cases, collapse and sudden cardiac arrest
Important note: If you have chest pain or pressure, you may be having a heart attack. Call for help immediately.5
Do you need treatment?
Most arrhythmias are considered harmless and are left untreated. Once your doctor has documented that you have an arrhythmia, he or she will need to find out whether it's abnormal or merely reflects the heart's normal processes. He or she will also determine whether your arrhythmia is clinically significant – that is, whether it causes symptoms or puts you at risk for more serious arrhythmias or complications of arrhythmias in the future. If your arrhythmia is abnormal and clinically significant, your doctor will set a treatment plan. View an animation of arrhythmia.4
- Especially for people with AFib, prevent blood clots from forming to reduce stroke risk
- Control your heart rate within a relatively normal range
- Restore a normal heart rhythm, if possible
- Treat heart disease/condition that may be causing arrhythmia
- Reduce other risk factors for heart disease and stroke
Living with Arrhythmias
- Take all medications exactly as prescribed.
- Never stop taking any prescription medication without first consulting your healthcare provider.
- If you have any side effects, tell your healthcare provider about them.
- Tell your healthcare provider about all your other drugs and supplements, including over-the-counter medications and vitamins.
Monitor your pulse4
You should know how to take your pulse – especially if you have an artificial pacemaker.
- Put the second and third fingers of one hand on the inside of the wrist of the other hand, just below the thumb OR on the side of your neck, just below the corner of your jaw.
- Feel for the pulse.
- Count the number of beats in one full minute.
- Keep a record of your pulse along with the day and time taken and notes about how you felt at the time.
Certain substances can contribute to an abnormal/irregular heartbeat, including:
- Cold and cough medications
- Appetite suppressants
- Psychotropic drugs (used to treat certain mental illnesses)
- Antiarrhythmics (paradoxically, the same drugs used to treat arrhythmia can also cause arrhythmia. Your healthcare team will monitor you carefully if you're taking antiarrhythmic medication.)
- Beta-blockers for high blood pressure
- Street drugs such as cocaine, marijuana and “speed” or methamphetamines
If you're being treated for arrhythmia and use any of these substances, be sure to discuss this with your doctor.
Manage your risk factors4
Just having certain arrhythmias increases your risk of heart attack, cardiac arrest and stroke. Work with your healthcare team and follow their instructions to control other risk factors:
- Reduce high blood pressure
- Control cholesterol levels
- Lose excess weight
- Eat a heart-healthy diet
- Avoid tobacco smoke
- Enjoy regular physical activity
- American Heart Association. Why Arrhythmia Matters. Available at https://www.heart.org/en/health-topics/arrhythmia/why-arrhythmia-matter. Accessed 13 May 2020.
- American Heart Association. About Arrhythmia. Available at https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia. Accessed 13 May 2020.
- American Heart Association. Understand your Risk for Arrhythmia. Available at https://www.heart.org/en/health-topics/arrhythmia/understand-your-risk-for-arrhythmia. Accessed 13 May 2020.
- American Heart Association. Treatment and Prevention of Atrial Fibrillation. Available at https://www.heart.org/en/health-topics/atrial-fibrillation/treatment-and-prevention-of-atrial-fibrillation. Accessed 13 May 2020.
- American Heart Association. Symptoms, Diagnosis and Monitoring of Arrhythmia. Available at https://www.heart.org/en/health-topics/arrhythmia/symptoms-diagnosis--monitoring-of-arrhythmia. Accessed 13 May 2020.