Cardiovascular Services
College of Medicine

Atrial Fibrillation

  • In atrial fibrillation, the heartbeat is irregular and rapid, sometimes beating as often as 300 times a minute in the upper chambers (atria) and 100-150 times a minute in the lower chambers (ventricles), about four times faster than normal. Blood does not move through the heart in a normal way, which may increase the risk of clots and stroke. If treated appropriately, atrial fibrillation seldom causes serious or life-threatening problems. Effective treatment for atrial fibrillation returns the heart to a normal rhythm or controls the heart rate, and prevents blood clots and strokes.

  • Atrial fibrillation can be symptom-free or can cause uncomfortable symptoms. Do you have shortness of breath when climbing steps or exerting yourself?  Do you have frequent palpitations?  Has your ability to exercise declined?  Do you experience chest pain?  Have you had episodes of dizziness or fainting?

    WHAT ARE THE SYMPTOMS OF ATRIAL FIBRILLATION?

    Some people develop atrial fibrillation without any apparent cause. For others, a wide range of risk factors may contribute to the disease. Risk factors include: Diabetes, High blood pressure, Coronary heart disease, Mitral valve disease, Thyroid disease, Chronic lung disease, Recent open-heart surgery, Age is a risk factor; atrial fibrillation is most common in people over 60. Certain lifestyle choices can bring about or exacerbate the condition. For instance, excessive alcohol consumption or using stimulating drugs such as caffeine, decongestants and cocaine can contribute to atrial fibrillation.

          International Normalized Ratio (INR)

  • An INR is useful in monitoring the impact of anticoagulant (“blood thinning”)medicines, such as Warfarin(Coumadin). Patients with atrial fibrillation often take anticoagulant medications to protect against clots that can cause strokes. While taking Warfarin, patients have regular blood tests to monitor their INR. Just as patients know their blood pressure numbers, they also should know their Warfarin (Coumadin) dosage and their INR. In healthy people, the INR is about 1.0. For patients on anticoagulants, the INR typically should be between 2.0 and 3.0 for patients with atrial fibrillation, or between 3.0 and 4.0 for patients with mechanical heart valves. However, the ideal INR must be individualized for each patient. An INR can be too high; a number greater than 4.0 may indicate that blood is clotting too slowly, creating a risk of uncontrolled bleeding. An INR less than 2.0 may not provide adequate protection from clotting.

          TREATING ATRIAL FIBRILLATION WITH CATHETER 

  • Ablation is known by several names, including cardiac ablation, catheter ablation, radiofrequency ablation, and cardiac catheter ablation. Ablation for atrial fibrillation, the most common type of arrhythmia, is usually reserved for patients with symptoms that have not responded to medication. Ablation is typically most successful in those who continue to have paroxysmal (comes on suddenly) atrial fibrillation that ends on its own.

  • An ablation is a procedure designed to use energy to disrupt or eliminate the faulty electrical pathways that cause abnormal heart rhythms. Like many cardiac procedures, ablation no longer requires open heart surgery. Rather, it can be done through catheters placed into the heart through the blood vessels. Catheters (narrow, flexible wires) are inserted into a blood vessel, often through a site in the groin or neck. They are then guided via x-ray through the blood vessels and directed to the heart muscle. Once the catheters are in place in the heart, heat or another form of energy is directed to areas of the heart that are sending out the abnormal electrical signals that cause atrial fibrillation. Then, a burst of energy destroys the specific problematic tissue and creates an area of tissue that will not conduct electrical activity. Most healthy tissue is left unharmed. In ablation, energy either destroys the troublesome areas that trigger abnormal electrical signals or creates a roadblock that stops such signals from traveling through the heart.

  • Typically patients are seen by the cardiologist performing the procedure within a month or two following the procedure for an examination and an electrocardiogram. Usually after a period of about three months, decisions are made about continuation or discontinuation of any medication. After that, the follow-up evaluations may be as infrequent as once every 6 to 12 months.