Types of AFib
Variations of AFib fall into five separate categories depending on how often they occur.
- Lone AFib occurs in people under 60 years of age with no known conditions connected to the disease. Lone AFib can have no symptoms and often appears during a standard physical exam. When symptoms do happen, they can disappear in a few minutes and not return for days, months, or years.
- Paroxysmal AFib starts spontaneously and can resolve on its own without medical treatment. Episodes can last from seconds to days. Symptoms are often more significant than with other variations of AFib.
- Persistent AFib can also begin without warning but continues for at least a week and doesn’t always stop by itself. Medical treatment is often necessary to halt the occurrence.
- Long-standing persistent AFib lasts for one year or longer without resolution. This type is often linked to damage to the heart’s structure, and is difficult to manage, and can require interventional procedures because medications are not sufficient.
- Permanent AFib happens when treatment for long-standing persistent AFib fails to convert the arrhythmia back to normal. People with this variety are in AFib at all times and experience a decreased quality of life due to severe symptoms and are at an elevated risk for a critical cardiac event.
Is Atrial Flutter a Type of AFib?
Atrial flutter, although not technically a form of AFib, is often grouped in with AFib because the atria beat faster than usual and cause a rapid heart rate. The difference between the two is that in atrial flutter the atrial contractions are regular instead of irregular.
Atrial flutter produces two to four atrial contractions for every ventricular contraction. Many physicians view atrial flutter as less problematic than AFib because flutter waves are more likely than fibrillation waves to convert back to a normal rhythm in most people, and the risk of blood clot formation is lower than with AFib.
What Happens When the Heart Goes into AFib
AFib occurs because the atria, located at the top of the heart, receive many electrical signals from areas of heart and lungs other than those from the SA node. Because of the sheer volume of these added impulses, the atria lose their carefully coordinated connection with the ventricles.
Specialized heart cells can automatically initiate an electrical signal, as can specific areas of lung tissue. Put these two together, each firing at different times, and you have a rapid, and irregularly beating bundle of muscle that doesn’t move enough blood so that the rest of the body does not receive enough of the nutrients that it contains.
The periodic, random signals the atria receive can cause them to contract rapidly in an unsynchronized fashion. Many, but not all the impulses received at the atrial level travel down below to the ventricles to signal them to pump.
The excessive signals passed from the atria to the ventricles produce a resting heart rate in the range of 100 to 175 beats per minute.
Over time, this consistently fast heart rate can lead to a weakened heart muscle, which is a condition known as congestive heart failure
Atrial fibrillation means that the atria are quivering (fibrillating) instead of fully contracting. The incomplete pumping prevents the atria from emptying their full volume of blood, which interferes with the body’s regular circulation pattern.
When blood remains in the atria after an incomplete contraction, it begins to pool. Pooling leads to an increased chance of clots to form, which can then migrate to other places in the body and cause blockages that can elicit a stroke.
The lack of an adequate blood supply flowing to the rest of the body creates a variety of symptoms that are often serious.
Symptoms of AFib
AFib has a myriad of symptoms that can vary depending on the type you have. Individuals can experience mild to severe AFib symptoms, while some people have none, and the presence of the condition initially appears during a routine physician’ s examination.
According to the American Heart Association, people with AFib that present with no symptoms has a fivefold increase in the risk of suffering a stroke than someone with no previous history of AFib.
The following symptoms commonly associated with AFib are:
- Abnormal sweating
- Having difficulty with walking and balance
- Feeling like you are going to faint
- Pain, pressure, or tightness in the chest
- Unusual fatigue
- Shortness of breath
- An uncomfortable, tight sensation in the neck
- A racing, irregular heart rate that is too fast to count when checking your pulse at your wrist
- Palpitations or a feeling of your heart pounding or fluttering
- Weakness at rest or with activity
- Having an uneasy feeling that is difficult to explain
- Some individuals wake up from sleep due to a bout of AF
AFib symptoms differ from those associated with a heart attack due to the presence of palpitations or fluttering sensations. If you experience chest pain with AFib, call 911 because it’s possible that you are suffering a heart attack.
Because AFib also carries an elevated risk of stroke, it’s important to know the warning signs, which are:
- Slurred or loss of speech
- Sudden changes in vision
- One-sided weakness or numbness, especially in an arm or the face
Next page: The treatment and management of AFib.