Atrial fibrillation (“a-tree-uhl fih-bruh-lay-shun”), or A-fib, is an irregular heart rhythm (arrhythmia) that starts in the upper portion (atria) of the heart. A-fib affects more than 5 million Americans and is the most common arrhythmia that leads to hospitalization. A-fib is the leading cause of stroke and is associated with an increase in morbidity and mortality. During A-fib, the upper chambers of the heart beat rapidly and erratically in a chaotic way without any effective muscle contraction. A-fib may develop as a result of changes in the heart due to age. Hypertension (high blood pressure), valvular heart disease, coronary artery disease, over-activity of the thyroid gland or excessive alcohol intake may promote A-fib. There can also be a genetic component. A-fib can be a progressive disease. It can start as intermittent episodes and may progress into a persistent then permanent form with associated structural changes in the heart. Earlier treatment and intervention is usually associated with a more favorable response to therapy.
Symptoms of A-fib: What to look for
Symptoms of atrial fibrillation vary. Some come and go, while other symptoms are persistent. Often, people don’t experience any symptoms, which makes the condition difficult to diagnose. Approximately one-third of those who have A-fib may not be aware of it. A-fib symptoms may include:
- Fluttering, racing or pounding of the heart
- Feeling dizzy or lightheaded
- Feeling out of breath
- Feeling weak and tired
- Chest pain (angina)
Timely treatment is key
Atrial fibrillation is dangerous because it greatly increases the risk of stroke. In fact, A-fib is the leading cause of stroke if not treated in time. If the heart doesn’t beat strongly, blood can collect, or pool, in the atria, where clots are likely to form. If the heart pumps a clot into the bloodstream, the clot can travel to the brain and block blood flow, causing a stroke. Most people who have atrial fibrillation need to take a blood-thinning medicine to help prevent stroke, although the dangers of an anti-coagulant must be weighed against the risk of stroke.
First and foremost, an assessment must be made to decide on the risk of stroke. Atrial fibrillation can also lead to heart failure. A number of treatments may be used for atrial fibrillation, depending on an individual’s symptoms and risk of stroke. A procedure known as electrical cardioversion can be used in patients with atrial fibrillation. Although it is very effective in restoring the normal rhythm, atrial fibrillation often recurs after the cardioversion unless other measures are taken. Usually antiarrhythmic drugs are tried first. However in patients in whom drugs have not been effective, well tolerated or preferred, catheter ablation offers an effective treatment option.
Take the next step:
- Download the University of Michigan Electrophysiology Service’s “The Treatment of Atrial Fibrillation” PDF.
Dr. Hakan Oral is Director of the University of Michigan Cardiac Electrophysiology Service and Frederick G.L. Huetwell Research Professor of Cardiovascular Medicine. He has clinical interest in catheter ablation of all arrhythmias and atrial fibrillation, ICDs and pacemakers.
The University of Michigan Samuel and Jean Frankel Cardiovascular Center is a top ranked heart and heart surgery program among Michigan hospitals. To learn more, visit our website at umcvc.org.