What's The Difference Between Atrial Flutter And Atrial Fibrillation?

The most common type of arrhythmia, atrial fibrillation is notable as a health risk for older people. Arrhythmia describes an abnormal heartbeat, and a vast number of heart conditions fall under this category. Although an "abnormal heartbeat" sounds like bad news, there are symptomless and even healthy arrhythmias.

Several arrhythmias are dangerous, however, and can lead to anything from mildly dangerous to life-threatening symptoms. Atrial fibrillation is closer to the latter type of arrhythmia. It won't immediately cause life-threatening effects, but it can get worse and cause, for example, strokes.

Atrial flutter and atrial fibrillation: What's the difference?

The heart has two chambers. The upper chambers are called atria, and the lower chambers are called ventricles. Blood is pumped from the top of the heart to the bottom, so it can be moved to the rest of the body. It controls the muscles with electrical signals from something called the "sinoatrial node". Normally, this allows your heart to beat at a normal pace.

In atrial fibrillation, this is not the case. The sinoatrial node loses control of the electrical signals, and errant electrical signals bombard the atria, telling it to make a heartbeat. Unable to keep up with the demand, it vibrates more than it pumps blood. With such a short amount of time to process these demands, the heart inevitably becomes less competent at pumping blood satisfactorily.

Atrial flutter is similar, but instead of the chaotic and random electrical impulses that cause atrial fibrillation, atrial flutter is the result of consistent electrical loops in the heart. Because they travel down electrical pathways that cause them to loop, they send excessive amounts of electrical signals. It is similar to atrial fibrillation, where the atria now beat too fast, but in atrial flutter, it beats quickly in a consistent pattern instead of an erratic one.

Fortunately, this doesn't cause the entire heart to beat this quickly. The signals are slowed down as they reach the ventricles, so the bottom half of the heart does not beat as fast. Nonetheless, it's still much more ineffective at pumping blood through the body and is thus dangerous to the victim's health. 

What should you expect from each one?

The symptoms

Unsurprisingly, the symptoms of the two arrhythmias are very similar. These can include:

• Racing or irregular pulse
• Feeling your heartbeat
• Lightheadedness
• Fainting
• Fatigue
• Inability to exercise
• Shortness of breath
• Chest pain

This shouldn't necessarily be considered a good thing, or a sign that atrial fibrillation or flutter does not require treatment. Even without symptoms, your health can be in danger. Because the heart has become less effective at pumping blood, blood may pool within it and cause blood clots that can lead to strokes and other complications.

One difference between the two is that despite having similar rates of mortality, atrial fibrillation tends to cause death more quickly, whereas atrial flutter "catches up" later. This means that if atrial flutter is identified earlier, patients have a better chance of survival.

Causes and diagnosis

The causes and diagnosis of atrial fibrillation and flutter are almost identical, along with those of many other heart conditions. This is because there are a few common causes of heart damage, and the same tools are generally used to analyze the heart. The causes of atrial fibrillation and flutter can include:

• Alcohol, but especially binge drinking
• Sick sinus syndrome, another type of arrhythmia
• Hyperthyroidism
• Certain medications
• Heart diseases, heart surgery, Heart attacks, heart failure, or heart abnormalities
• Living in drier air and colder environments
• Smoking (Especially for atrial flutter)

These conditions are generally diagnosed using an ECG (electrocardiogram), which records the heart's electrical activity. Because atrial fibrillation and flutter involve improper electrical activity in the heart, an ECG is usually enough to make a diagnosis. A doctor may also investigate your family history and pulse. The symptoms of arrhythmia can be periodical, and in that case, different devices may be used to monitor the heart over an extended period of time. These generally include a Holter monitor (24-hour monitor), event monitor (three to four week monitor), or a loop recorder (which can record for months to years).

Treatments

At first, the heart is usually given electrical shocks, or drugs are inserted through a vein to temporarily return the heart to its normal functioning. Different medications can be administered after that, including drugs to slow the heartbeat or try to prevent atrial fibrillation or flutter from returning.

However, in many situations, it does return anyway. A procedure called radiofrequency ablation, which destroys and scars problematic parts of the heart, is also used. However, this is much more effective when the patient has atrial flutter because there is usually only a small area generating the problem and removing that can generally cure it. However, with atrial fibrillation, it's harder to recognize where the problem lies.

After ablation, the patient may require a pacemaker, and blood-thinning medicines may be used if ablation is unsuccessful. These make clots in the heart or strokes much less likely. Finally, if the patient cannot take thinning medicines, a device called the Watchman device can be placed inside the heart and catch blood clots.