Atrial flutter is a type of heart rhythm abnormality that usually results in the heart beating too quickly. It may cause people to experience heart palpitations, fatigue, shortness of breath, and/or chest pain. Sometimes, however, there are no symptoms, so people don’t know they have the condition. It’s important to know that atrial flutter, if left untreated, increases a person’s risk of stroke or cardiomyopathy, a weakened heart muscle.  

Atrial flutter is most commonly seen in older people. Other risk factors include hypertension, diabetes, obesity, lung disease, overactive thyroid, and other heart conditions, including previous heart surgery.  

A number of treatments are available for atrial flutter, including medications and medical procedures. These interventions help to lower stroke risk and improve symptoms.

Atrial flutter, a heart rhythm problem, occurs because of a malfunction in heart’s electrical system, leading to a faster-than-normal heart rate.  

When the heart functions normally, electrical impulses originate within the upper right-hand chamber of the heart, in an area called the sinoatrial node. These electrical impulses help the heart muscle to contract in such a way that blood passes through its four chambers efficiently, then is sent throughout the body.  

If a person has atrial flutter, the atria may develop an electrical loop, overwhelming the sinoatrial node. This causes the heart’s upper chambers to contract more often than they should, though the contractions may still occur at regular intervals.  

When this happens, the heart’s upper chambers contract too fast for all the electrical impulses to conduct to the heart’s lower chambers. For example, the upper chambers may contract 300 times per minute, while the lower chambers may contract 150 times per minute. This would cause the heart rate to increase to 150 beats per minute, which is much higher than the normal range (60 to 100 beats per minute).

These too-fast contractions in the heart’s upper chambers mean that blood does not pump efficiently to the lower chambers or throughout the body, leading to a number of potential serious complications. For example, blood left behind in the upper chambers may pool, forming blood clots. These blood clots may increase the risk of stroke, should they detach and move through the bloodstream to the brain. In addition, prolonged periods of high heart rates can lead to a weakening of the heart (cardiomyopathy).

The following conditions, which may damage the electrical system that powers the heart, may cause atrial flutter:

• Heart attacks
• Open-heart surgery
• Chronic obstructive pulmonary disease (COPD)
• A blood clot in the lung (pulmonary embolism)
• Diabetes
• Overactive thyroid (hyperthyroidism)
• High blood pressure (hypertension)

People who have symptoms of atrial flutter may experience:

• A heartbeat that is faster than normal
• Chest pain
• Heart palpitations
• Shortness of breath
• Fatigue
• Feeling unexpectedly tired from physical exertion
• Lightheadedness
• Dizziness
• Low blood pressure
• Fainting

Some people with atrial flutter have no symptoms and aren’t aware they have the condition.

People who are at increased risk of atrial flutter include those who:

• Are older
• Are male
• Are overweight or obese
• Have high blood pressure
• Have diabetes
• Have sleep apnea
• Have chronic lung disease, such as chronic obstructive pulmonary disease
• Have had a pulmonary embolism
• Have thyroid disease, particularly overactive thyroid
• Have a family history of atrial flutter
• Have had a heart attack
• Have heart valve abnormalities
• Experience atrial fibrillation
• Are in heart failure
• Have had heart bypass surgery
• Have recently had surgery for any other condition
• Have alcohol use disorder
• Are binge drinkers
• Smoke
• Use illegal drugs
  

If you have symptoms of atrial flutter, talk to your doctor. To diagnose the condition, they will need to know about your medical history, perform a physical exam, and order diagnostic tests.  

During the medical history part of the visit, you should tell your doctor about a personal history of heart disease, heart attack, heart failure, or heart surgery, as well as any chronic health conditions, such as sleep apnea, hypertension, COPD, diabetes, or overactive thyroid. You should also let your doctor know if you have a family history of atrial fibrillation.  

During a physical exam, doctors may check to see if your heart rate is higher than normal, and if your pulse is irregular.  

Different diagnostic tests may help rule out other conditions and/or diagnose atrial flutter. Blood tests, for example, may help diagnose thyroid disease, which may contribute to atrial flutter, or the tests may rule out other conditions. Additionally, you may have the following tests performed:

• Electrocardiogram, which measures the heart’s electrical activity. A patient with atrial flutter won’t have normal heart wave patterns; instead, their heart waves may have a “sawtooth” pattern, or the study may show other abnormalities associated with atrial flutter.
• An echocardiogram, which provides detailed images of your heart while it is beating. This may reveal heart valve or structural heart problems or the presence of blood clots.
• A heart monitor, which records the heart’s activity for the hours or days that you wear it. This is useful in detecting atrial flutter that occurs intermittently, especially if it isn’t present during a doctor visit.
• A stress test, in which you exercise while an electrocardiogram measures your heart’s electrical activity. Doctors may be able to identify atrial flutter with this test.
• A CT scan, MRI or X-ray, which can provide images of your heart. This may help doctors identify scar tissue in the heart, heart failure, lung problems, or blood flow abnormalities.

First-line treatments for atrial flutter aim to slow the heart rate (with amiodarone, digoxin, beta-blockers or calcium channel blockers) and to reduce the risk of clotting (with heparin, warfarin, or other anticoagulants).  

Procedures that help treat this condition include:

• Catheter ablation, in which heat, cold, or laser light is directed at the specific area within the heart that is causing atrial flutter, with the goal of destroying the tissue and blocking the electrical loop. To do this, doctors thread a thin wire through the patient’s blood vessels until it reaches the heart, then apply radiofrequency waves (radiofrequency ablation), extreme cold (cryoablation), or laser light (laser ablation), causing the formation of scar tissue. The heart rhythm should return to normal after this procedure.
• Cardioversion, during which an external electrical shock is applied to the heart to change its rhythm, to return the upper chamber contractions to normal.
• Pacemaker, a small device that is implanted near the heart, which may help the heart to maintain a regular, healthy pace if other, more definitive therapies are not possible.
• Surgery may also be an option for certain patients, depending on their circumstances and the severity of the condition.

Ablation can be curative for the majority of patients with atrial flutter, and for those who can’t be treated with ablation, the condition that can be managed with medications and other procedures, if necessary. Untreated atrial flutter increases the risk of stroke or cardiomyopathy.

“The Yale Cardiac Electrophysiology Program is an internationally recognized center for expertise in the management of arrhythmias, including atrial flutter,” says Yale Medicine cardiologist James V. Freeman, MD, MPH, MS. “Yale offers state-of-the-art care, incorporating the latest medical and procedural innovations in the field to treat each patient in an individualized way. In addition, our faculty conducts cutting-edge research into the underlying mechanisms and optimal treatment strategies for patients with arrhythmias, including atrial flutter.”