Atrial fibrillation is one of the most common cardiac arrhythmias, and it can be one of the most frustrating to deal with. While atrial fibrillation is not in itself a life-threatening arrhythmia, it often causes significant symptoms, and it can lead to more serious problems, such as stroke and worsening heart failure in people with heart disease.
Furthermore, as a general rule, whenever several different therapeutic approaches are available for any medical condition, it means that no "ideal" or "best" approach has yet been identified. Deciding among the various treatment options is likely to be less than entirely straightforward. This is the case for atrial fibrillation. Several kinds of treatments are being used, and the optimal treatment is quite unsettled.
If you have atrial fibrillation, you should try to learn everything you can about this arrhythmia and the available treatments, so you can work with your doctor to decide which treatment option is right for you.
What Is Atrial Fibrillation?Atrial fibrillation is an irregular heart rhythm, caused by extremely rapid and chaotic electrical impulses that are generated in the heart's atria (the two upper chambers). This kind of rapid, chaotic electrical activity is called "fibrillation."
When the atria begin fibrillating, three things happen. First, the heart rate tends to become rapid and irregular. The AV node is bombarded with frequent, irregular electrical impulses coming from the atria, and as many as 200 impulses per minute are transmitted to the ventricles, leading to a fast and very irregular heart beat.
Second, when the atria are fibrillating, they are no longer contracting effectively. So the normal coordination between the atria and the ventricles is lost. As a result, the heart works less efficiently.
And third, because the atria are no longer contracting effectively, after a time (usually after about 24 hours) blood clots can begin to form in the atria. These blood clots can eventually break off and travel to the brain, producing a stroke.
Symptoms of Atrial FibrillationWhile some people with atrial fibrillation have only minimal symptoms, in most cases the arrhythmia is very noticeable and quite disturbing. The most common symptom is palpitations, which are usually perceived as a rapid, irregular heart beat. It is also common to be easily fatigued, short of breath and (occasionally) light-headed.
In fact, if the heart rate associated with atrial fibrillation is rapid enough and persists long enough (for at least several months), this arrhythmia can actually cause heart muscle weakness and heart failure.
The most dire consequence of atrial fibrillation, however, is the possibility of stroke.
What Causes Atrial Fibrillation?Atrial fibrillation can be produced by several cardiac conditions, including CAD, valvular heart disease, chronic hypertension, pericarditis, heart failure or virtually any kind of heart problem. This arrhythmia is also fairly common with hyperthyroidism, pneumonia or pulmonary embolus (blood clot to the lung).
Ingestion of caffeine, amphetamines or other stimulants (such as cold remedies containing pseudoephedrine) can cause atrial fibrillation in some people, as well as after drinking as few as one or two alcoholic beverages - a condition known as "holiday heart."
But a very large proportion of people with atrial fibrillation have no identifiable reason for it. They are said to have "idiopathic" atrial fibrillation. Idiopathic atrial fibrillation is often a condition associated with aging. For example, while atrial fibrillation is rare in patients under 50, it is quite common in people who are 80 or 90 years old.
Types of Atrial FibrillationDoctors often classify atrial fibrillation into several types. But to help you decide which treatment approach is right for you it is useful to lump these types into only two categories:
- New onset or intermittent atrial fibrillation. Here, the atrial fibrillation is either a brand-new problem or a problem that occurs only intermittently. Intermittent atrial fibrillation is often called paroxysmal atrial fibrillation. People in this category have a normal heart rhythm the vast majority of the time. Episodes of atrial fibrillation are relatively brief and infrequent.
- Chronic or persistent atrial fibrillation. In this type, atrial fibrillation is either present all the time or occurs so often that periods of normal heart rhythm are infrequent or short-lived.
Treating Atrial FibrillationIf it were easy and safe to do so, clearly the best treatment for atrial fibrillation would be to restore and maintain the normal heart rhythm. Unfortunately, in many cases it is neither safe nor easy.
In many instances, especially if atrial fibrillation has been present for weeks or months, it is exceedingly difficult to maintain a normal rhythm for more than a few hours or days. This unfortunate fact has required two different general treatment approaches for atrial fibrillation.
The "rhythm control" approach attempts to restore and maintain a normal heart rhythm. And the "rate control" accepts atrial fibrillation as the new "normal" heart rhythm, instead aiming to control the heart rate (to greatly diminish the symptoms of atrial fibrillation), as well as reduce the risk of stroke with anti-coagulation (that is, with blood thinners).
Until recently, doctors felt that if they were successful in applying the rhythm control approach, their patients would no longer have an elevated risk of stroke and anti-coagulation would not be needed. Recent evidence, however, suggests that the majority of people with atrial fibrillation will require stroke-prevention therapy, regardless of which treatment approach is used.
Which of these two approaches - "rhythm control" or "rate control" - is the right one for you will depend on many factors, including how long you have had the arrhythmia, your age, your underlying heart diseases (if any) and your ability or willingness to tolerate various kinds of drugs or invasive procedures.
Deciding on the right treatment is the most important issue with atrial fibrillation, and it can be a relatively complex one. The more you understand it, the more you will be able to help your doctor make the treatment decisions that are right for you.
Fuster, V, Ryden, LE, Cannom, DS, et al. ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation). J Am Coll Cardiol 2006; 48:e149.