What is a heart arrhythmia and what causes it?

Typically, hearts will have a regular rhythm that can get slower or faster based on what you’re doing. If you have a heart arrhythmia, it means that the rhythm of your heart is off or unusual – and in many cases, there doesn’t seem to be a clear reason.

For example, you might wake up from sleep with a racing heart, feel a flutter in your chest while sitting on the couch or notice gaps between heartbeats during an evening walk. It’s also possible to have an irregular heartbeat and have no symptoms at all.

Most changes to your heart’s rhythm are temporary and go away on their own. But some heart arrhythmias require medical treatment. Below, we’ll provide more information about heart arrhythmias, causes, symptoms and when to get help.

What is a heart arrhythmia?

A cardiac arrhythmia is some sort of irregular heartbeat. You may have one if:

Your heart is beating faster than normal.
Your heart is beating slower than normal.
You have erratic changes in heartbeat where beats seem to be added or dropped at random.

What are heart arrhythmia symptoms?

Symptoms of a heart arrhythmia can include:

Heart palpitations – which can feel like skipped heartbeats or a fluttering in your chest
Racing heartbeat – it may feel like your heart is pounding
Slow heartbeat
Chest pain or tightness
Shortness of breath
Lightheadedness or dizziness
Sudden fainting
Anxiety
Low blood pressure
Fatigue

Because it’s possible to have an irregular heartbeat without obvious symptoms, you may not know you have one until your doctor finds it during a yearly checkup. This is just another reason why preventive care is so important.

How serious is an irregular heartbeat?

Anyone can have an irregular heartbeat from time to time. Sometimes it’s nothing to worry about. But some changes in your heartbeat can be concerning because they affect how much blood gets to your lungs and the rest of your body.

Rapid, slow or irregular heartbeats that happen rarely usually don’t need medical care. But contact your doctor if you have heartbeat changes frequently, they don’t go away or if you have other symptoms like shortness of breath, dizziness or lightheadedness.

If you’re experiencing signs of a heart attack such as severe chest pain, shortness of breath, rapid heart rate or dizziness, call 911 immediately to get medical care.

What causes a heart arrhythmia?

Simply put, heart arrhythmias happen when one or more parts of your heart are blocked, weakened or otherwise malfunctioning. But to understand common heart arrhythmia causes, it helps to know a little about your heart and how different parts affect its rhythm.

How the sinus node affects your heart rhythm

The sinus node is a group of special heart cells that creates a momentary electrical signal that travels through the heart, causing it to contract. This contraction is what makes a heartbeat.

The normal adult heartrate is between 60-100 beats per minute (bpm). Children’s heartbeats are very fast at birth (90-165 bpm for newborns) but about the same as adults by the time they reach adolescence.

The sinus node can be thought of as a natural pacemaker for the heart. If it doesn’t work properly, you may have an irregular heartbeat – your heart may beat too fast or too slow, or you may have skipped heartbeats.

How the ventricles and atria affect your heart rhythm

Two ventricles and two atria make up the four chambers of the heart. Each chamber plays a different role in making your heart beat.

Top chambers: The upper chambers are atria, responsible for receiving and collecting blood.
Bottom chambers: The lower chambers are ventricles, and their purpose is to pump the blood.
Right chambers: The right atrium and ventricle work together to push blood to the lungs so that the blood can be filled with the oxygen your body needs.
Left chambers: The left atrium and ventricle collect the oxygen-rich blood from the right side of the heart and push it out to the rest of the body.

If even one chamber isn’t working correctly, it can throw off the heart’s rhythm, causing an irregular heartbeat.

What are the types of heart arrhythmias?

Cardiac arrhythmias affect your heart in different ways, based on where they occur and what causes them. Here’s what you need to know:

Premature heartbeats

It’s not uncommon for a heart to add a beat. This change in rhythm can make you feel like your heart is fluttering or has skipped a beat. Generally, these types of irregular heartbeats are nothing to worry about.

Bradycardia

A resting heartbeat lower than 60 bpm is considered bradycardia. Slow heartbeat can be caused if the sinus node is failing or if something is blocking the electrical system within your heart. If your heartbeat gets too slow, it might not push enough oxygen-rich blood out through your body, and you may faint or stop breathing.

Of course, a low resting heart rate isn’t always a problem. If you exercise regularly, your body may get enough blood even if your heart is pumping less than 60 bpm.

Types of bradycardia that may need medical attention include:

Sick sinus syndrome – If you have scarring near the sinus node, it can slow or block the electrical impulses, resulting in sick sinus syndrome. If you have this condition, you may have an irregular heartbeat or your heart’s rhythm may flip-flop between fast and slow heartbeats. This usually happens to older adults.
Heart block – You can have slow or skipped heartbeats if there’s a block in the electrical pathway between the sinus node and a collection of cells called the AV node. Because electrical impulses don’t move as well through the heart, your heart may not beat like it should. Most people who have a heart block have heart disease, and often have had a heart attack.

Tachycardia

A resting heart rate greater than 100 bpm is considered tachycardia. A fast heart rate can cause different problems based on where it happens.

Tachycardia in the upper heart

There are several different types of rapid heartbeats that can happen in the upper chambers of the heart, including:

Supraventricular tachycardia – This is a fast heartbeat that starts in the heart’s upper chambers. “Supraventricular” means above the ventricles. If the supraventricular tachycardia is short-lived and goes away on its own, it’s considered paroxysmal supraventricular tachycardia.
Atrial fibrillation (Afib) – This condition is caused by rapid, irregular signals in the upper half of your heart (between 350-600 bpm) that are upsetting its normal rhythm. As a result, the atria twitch uselessly, and you may not have a strong, steady heartbeat. Afib can be serious since it increases your chance of stroke, heart failure, and blood clots in your heart and lungs.
Atrial flutter – If you have an atrial flutter, it means that the upper chambers of your heart are beating very fast – between 240 and 340 bpm. It’s usually not life-threatening but can increase your chance of a stroke.

Tachycardia in the ventricles

Rapid or skipped heartbeats in the lower part of the heart tend to be the most serious arrhythmias, especially for people with heart conditions.

Ventricular tachycardia – If you have a rapid heartbeat in the lower chambers of your heart, the heart’s contractions may not be strong enough to push all the blood you need to your brain and the rest of your body. If you’re healthy, ventricular tachycardia may not always cause serious problems. But if you have heart disease, ventricular tachycardia can be an emergency situation.
Ventricular fibrillation – This type of arrhythmia occurs when fast, disorganized electrical signals cause the lower heart chambers to quiver uselessly instead of working to pump blood, and can cause a severe drop in blood pressure and sudden fainting. Ventricular fibrillation is the leading cause of sudden cardiac death.

Can you prevent a heart arrhythmia?

There are many factors that affect your heart’s rhythm – some relate to your overall health and others come from the choices you make. The good news is that, in many cases, you can reduce your risk of serious heart arrhythmia that require medical attention.

Heart arrhythmia risk factors based on health and medical conditions

Heart abnormalities – You can be born with conditions that affect your heart’s ability to work correctly. These abnormalities can be related to the heart’s electrical system or the heart itself. Working with a primary care doctor or a cardiologist can help you reduce your risks.
Changes to the heart over time – As you age, your heart changes, making it more likely that you’ll develop an arrhythmia. For example, you have a one in 10 chance of having atrial fibrillation if you over age 80. But if you’re under age 50, it’s very unlikely that you’ll have it. Staying on top of preventive care can help identify potential heart concerns.
Other heart conditions – People with heart disease or a previous heart attack are more likely to have certain types of arrhythmias. Still, by taking steps to reduce high blood pressure numbers and improve cholesterol levels, you can make it less likely that you’ll have an arrhythmia that requires medical care.
Illness and fever – When you’re sick, you may notice changes in your heart’s rhythm. Usually, these changes go away when you recover. But some people have lingering or new heart problems after an infection. Avoid getting sick by getting a flu shot every year and staying up to date on your preventive care.
Sleep apnea – If you have sleep apnea and can’t breathe properly during the night, you have a higher chance of getting serious arrhythmias. So if you have sleep apnea, make an appointment with a sleep specialist.
Being overweight – Excess weight can cause changes to your heart and make it less effective at pumping blood. Even a small weight loss can reduce your chance of getting Afib and other arrhythmias.
Stress and anxiety – You likely know that stress and anxiety can set your heart racing. It’s usually not a big deal if you get stressed out every now and then. But if the pressure is constant, the stress can have lasting effects on your heart. Look for ways to manage stress – deep breathing, guided imagery, exercise are all good options, so is talking to a mental health professional.
Pregnancy – When you’re pregnant you can have minor changes in your heart rate or rhythm. This generally isn’t concerning unless you have risk factors for heart disease. But definitely bring up your concerns at your next prenatal appointment.

Heart arrhythmia risk based on triggering activities or substances

Smoking – A faster heartbeat and irregular heart rhythms are just a couple ways that smoking is bad for your heart (and the rest of your body). About one in 5 deaths in the Unites States is caused by smoking, according to the National Heart, Lung and Blood Institute. If you’d like help quitting, talk to your primary care doctor.
Drinking alcohol – When you drink, your body loses magnesium, a mineral that helps with normal heart rhythm. Drinking can also lead to dehydration and the loss of electrolytes that your body needs to work correctly. To lower your risk, limit the number of alcoholic beverages you drink each day – it should be no more than one for women and two for men.
Dietary supplements – Supplements such as goldenseal, oleander and motherwort can cause irregular heartbeats. This is one of the reasons you should always talk to your doctor about taking any supplements.
Exercise – Working out speeds up your heart rate and may also cause temporary changes in heart rhythm. And as mentioned earlier, being physically fit can lead to a lower resting heart rate since your heart pumps more effectively. But don’t let a heart rate change be an excuse to avoid being active. Getting regular exercise is helpful for nearly every aspect of your physical and mental well-being. Talk to your doctor about the heart-healthy workouts that make sense for you.
Medications – Irregular heartbeats can be caused by the overuse of prescription and over-the-counter medications used for asthma, colds and heart problems. So, make sure to read the labels.
Caffeine – Drinking coffee, soda or energy drinks can increase your heart rate or cause it to skip a beat. But most of the time, the rhythm changes caused by caffeine are temporary and go away on their own. Unless your doctor says otherwise, a moderate amount of caffeine (4-5 cups pf coffee a day) is probably fine. But keep in mind that caffeine is also found in nonprescription medicines.
Illegal drugs – Cocaine and methamphetamine stimulate the heart and can cause a variety of arrhythmias, including some that are fatal.

When should I see a doctor about an irregular heartbeat?

Often, changes in heartbeats and irregular heartbeats are temporary and nothing to worry about. But make an appointment with your primary care doctor or cardiologist if:

The changes in your heart rhythm are constant or don’t go away.
You feel lightheaded or dizzy when experiencing changes in your heart’s rhythm.
Your symptoms are more frequent or more severe.
You have a personal or family history of heart disease.
If you’ve had a heart attack.

In the time leading up to your appointment, it’s a good idea to keep a record of episodes of heart arrhythmia. Whenever you feel an irregular heartbeat, take a moment to write down what you’re doing, how fast your heart is beating and if your heart feels like it’s fluttering or pounding too hard. This information can make it easier for your doctor to diagnose what’s going on with your heart.

How is a heart arrhythmia diagnosed?

During your appointment, your doctor will ask you questions about your health and perform a physical exam. You may also need heart tests and screenings such as:

Electrocardiogram (EKG or ECG) – Measures your heart’s electrical energy to see how fast and effectively it is beating.
Echocardiogram (echo test) – Uses ultrasound imaging to take pictures of your heart as it beats. This helps your doctor understand how well your heart is pumping.

If your doctor thinks you may have a heart arrhythmia, they may ask you to use a device at home that collects information about changes in your heartbeat pattern.

What are heart arrhythmia treatments?

Treatment depends on the type or heart arrhythmia, what’s causing it and your overall health. If your irregular heartbeat needs care, your doctor or cardiologist may recommend one or more of these options:

Blood-thinning medicines – Make it less likely that blood will clot in your heart or lung, reducing your chance of a stroke.
Rate-control medicines – Control the rate your heart beats so it doesn’t go too fast or too slow.
Rhythm-control medicines – Help your heart beat with a normal rhythm.
Catheter ablation procedure – Treats small areas of the heart to create scar tissue that blocks the spread of abnormal electrical signals in the heart muscle.
Cardioversion procedure – Uses a precise controlled shock to get heartbeat back to normal.
Pacemaker – Sends regular electrical pulses to the heart to help keep its rhythm steady.
Implantable cardioverter defibrillators (ICDs) – Delivers an electrical pulse to help reset the heart when there’s a dangerously irregular heartbeat.
Lifestyle changes – For example, your doctor may recommend that you get more exercise, lose weight or eat a heart-healthy diet packed with fish, fruits, vegetables, beans, whole grains and good fats.

Heart arrhythmia help that’s in sync with your needs

Arrhythmias happen – even to healthy hearts – and it’s unlikely that you’ll be able to prevent every fast, slow or skipped heartbeat. But it’s totally possible to live with heart arrhythmia by takings steps to eat right, stay active and keep up on your preventive care.

If you’re concerned about how your heart is beating, start by talking to your primary care doctor. They’ll be able to provide you tips for managing mild arrhythmia symptoms and refer you to a cardiologist if you have a heart condition that requires more specific care.