How Atrial Flutter Is Treated

Atrial flutter is a cardiac arrhythmia—a condition defined by an abnormal heart rhythm. More specifically, it is an arrhythmia that typically causes tachycardia (a fast heart rate) and palpitations.

Atrial flutter is caused by extremely rapid, abnormal electrical impulses arising in the atria, the upper two chambers of the heart. About half of these impulses are transmitted to the ventricles, the lower two chambers, producing a heart rate usually around 150 beats per minute. The condition is related to atrial fibrillation, an irregular heart rhythm.

This article discusses what atrial flutter feels like and how it affects your health. It also covers who's at risk for it and how it's diagnosed and treated.

What Does Atrial Flutter Feel Like?

The rapid heart rate commonly produced by atrial flutter most often leads to pronounced symptoms including:

• Palpitations
• Dizziness
• Fatigue
• Change in mental status
• Dyspnea (breathlessness)

Like most reentrant arrhythmias, episodes of atrial flutter tend to come and go quite suddenly and unexpectedly.

If a person with atrial flutter also has coronary artery disease, the rapid heart rate can place enough stress on the cardiac muscle to cause angina. Severe chest pain is the classic symptom.

Atrial flutter can also produce a sudden worsening of symptoms in people who have heart failure.

What Causes Atrial Flutter?

Atrial flutter occurs when an electrical impulse becomes “trapped” in a circuit within the heart and begins spinning around and around. This causes frequent contractions of the heart muscle in the atria. It can happen after heart surgery, heart damage, or some other change in the heart.

What Are the Effects of Atrial Flutter?

Because the symptoms it produces can be intolerable, atrial flutter would be a significant arrhythmia even if all it did was cause uncomfortable symptoms.

However, this arrhythmia can be serious as it also tends to cause blood clots (thrombus formation) in the atria. These blood clots can break loose (embolize) and cause strokes.

Furthermore, atrial flutter is often a “bridge arrhythmia” to atrial fibrillation. This means people with atrial flutter often go on to develop chronic atrial fibrillation.

Who Develops Atrial Flutter?

While anyone can develop atrial flutter, it is not a common arrhythmia. It is much less frequent, for instance, than atrial fibrillation.

The people most likely to develop atrial flutter are the same ones also most likely to develop atrial fibrillation. These include people to whom any of the following apply:

• Obesity
• Lung disease (including pulmonary embolus)
• Sleep apnea
• Sick sinus syndrome
• Pericarditis
• Hyperthyroidism
• History of heart surgery

Diagnosing Atrial Flutter

Diagnosing atrial flutter is fairly straightforward. It merely requires capturing the arrhythmia on an electrocardiogram (ECG) and looking for what are called “flutter waves.”

Flutter waves are signals appearing on an ECG that represent the electrical impulse that is spinning around the atrial reentrant circuit.

What Is the Best Treatment for Atrial Flutter?

The goals of treatment for atrial flutter are to regulate your heart rate, reduce the risk of heart failure or stroke, and relieve any symptoms you may be experiencing.

The right treatment option for you depends on several factors, including:

• Whether or not your atrial flutter is caused by an underlying condition
• What symptoms you are experiencing and how they impact you
• Your risk level for having a stroke

There are several treatment options available that may be used to stop an acute episode or prevent episodes from recurring.

Stopping an Atrial Flutter Episode

In people who are having an acute episode, atrial flutter can be stopped quite readily with electrical cardioversion or by acutely administering antiarrhythmic drugs (usually, ibutilide or dofetilide).

If symptoms are severe during an acute episode, slowing the heart rate may be necessary while making preparations for cardioversion. This can often be accomplished quickly by administering intravenous doses of the calcium blockers diltiazem or verapamil, or the rapidly-acting intravenous beta blocker esmolol.

These drugs must be used cautiously, however, in people who also have heart failure.

Preventing Further Episodes

Once an acute episode has been dealt with, the next step is to attempt to suppress additional ones. In this regard, it is important to look for and treat any reversible underlying cause, such as hyperthyroidism, sleep apnea, or obesity.

Hyperthyroidism can usually be sufficiently controlled within a few days. Sleep apnea is also generally treatable within a reasonable period of time.

While obesity is also a reversible cause of atrial flutter, practically speaking, it is often not reversed sufficiently or quickly enough to assist substantially in treating this arrhythmia. Because of this, means beyond weight loss must be used to control atrial flutter.

If no readily reversible cause is found, treatment aimed directly at preventing atrial flutter is necessary. This will consist either of suppressing the arrhythmia with drugs or using ablation therapy, which creates small scarring in the heart to interrupt abnormal electrical activity.

Fortunately, ablating atrial flutter is usually a relatively straightforward procedure with a very favorable rate of success (well over 90%). However, there is a 10% to 33% chance of the flutter returning or atrial fibrillation occurring after ablation of the most common type of atrial flutter.

Nevertheless, In the large majority of people who have this arrhythmia, ablation ought to be strongly considered.

Since ablation works so well, resorting to a “rate-control strategy” (commonly used for atrial fibrillation) is only rarely necessary for atrial flutter. A rate control strategy means allowing the arrhythmia to occur and attempting to control the resulting heart rate in order to minimize symptoms.

Controlling the heart rate in atrial flutter is substantially more difficult than it is with atrial fibrillation. It commonly requires the use of a combination of beta-blockers and calcium blockers.

On occasion, getting the heart rate under control means ablating the heart’s normal conducting system to create a heart block, and then inserting a pacemaker to establish a stable heart rate. Often, getting rid of the atrial flutter altogether with an ablation procedure is the preferable course of action.

In any case, however, chronic anticoagulation therapy may be recommended to prevent stroke based on a person's unique risk factors, just as with atrial fibrillation.

Summary

Atrial flutter is an abnormal heart rhythm. It's caused by extremely rapid electrical impulses in the upper chambers of your heart. It can cause you to feel palpitations as well as dizziness, fatigue, and breathlessness. It can also increase your risk of stroke.

Atrial flutters are diagnosed with an ECG to show the electrical impulses of your heart. Treatment may include antiarrhythmic drugs, calcium blockers, and beta blockers. Prevention may also involve treating underlying causes, such as hyperthyroidism, sleep apnea, or obesity, or using ablation therapy.