Atrial Fibrillation Treatment
Carol Gilbert, coordinator at Aurora St. Luke's Atrial Fibrillation Ablation Center, explains atrial fibrillation (AF), how it can be treated and who is a good candidate for a procedure to relieve AF.
The first thing we need to do is work together to explore your conditions, discuss your goals and concerns, and identify appropriate options. Together, we can select the plan of care that meets your needs. Choices will be different for different people. The main goals of therapy are:
-
To restore your rhythm to normal
-
To control your rate in atrial fibrillation (AF)
Treatment needs to be specific to you, and your choices and goals are a big part of the treatment plan. Your plan of care will address your heart rate (pulse rate) and blood pressure. Treatment options will be carefully tailored to your specific medical condition and general health. Some of the conditions we take into consideration when determining appropriate choices are heart disease, heart failure, kidney disease, liver disease, abnormal thyroid function, weight and lung disease. Having these medical conditions does not mean you cannot have treatment for AF, including ablation, it means you will have special needs for monitoring or may have some limits to the options available due to concerns for your safety.
Simple lifestyle changes can help some people. For example, eliminating caffeine and stimulants, losing weight, treating thyroid conditions and eliminating sleep apnea are all things that can help reduce the frequency or severity of episodes and associated symptoms.
Atrial Fibrillation Treatment Options
You and your physician here at the Atrial Fibrillation Ablation Center, or your own personal doctor, need to discuss whether it is appropriate to focus on restoring your rhythm to normal rhythm or achieving control of your heart rate in atrial fibrillation. The process to manage your heart rhythm requires time and effort on the part of the physician and the patient. It can be discouraging for people looking for a quick fix. Many people find the effort to be worth it, and most patients feel better when their hearts beat in a normal (sinus) rhythm.
Radiofrequency Ablation
Radiofrequency ablation of your atrial fibrillation is one way to achieve rhythm control.
Read more about radiofrequency catheter ablation and one patient's experience at Aurora Medical Center in Grafton.
Epicardial Ablation
This ablation technique is used if conventional catheters and the energy they deliver cannot reach or penetrate certain areas of the heart involved in a rhythm disorder. When we do epicardial ablation in the electrophysiology procedure room (EP lab), we have all the EKG recording equipment, fluoroscopy (X-ray) and other images needed to guide catheters. A surgeon is added to our team to place the epicardial catheter through a tiny puncture near the breastbone. This procedure is called a pericardiotomy, or paracardioscopy and EX-Maze. It is also called a Convergent procedure or hybrid approach because it combines the use of catheters placed to touch the inside the heart (endocardium) using the standard vein punctures and the catheter placed to touch the outside of the heart (epicardium).
Alternative Ablation Techniques or Energy Sources
Several different energy sources are available to be used either in surgery or in the EP lab. Cryoablation or freezing energy is deliverable by catheters placed through veins or by surgical instruments applied directly to the heart by a surgeon during a coronary artery bypass or valve repair surgery. These are done by thoracotomy or open chest surgery so the surgeon can see the heart. Microwave is primarily used during the minimally invasive procedures where three to five small holes (sized like "thumb" or "keyholes") are made in the sides of the chest. Instruments or probes are passed behind the lungs and extended toward the heart. They then touch the outer heart (epicardial) surface where energy can be applied to ablate arrhythmias. Surgical ablations are almost always exclusively epicardial ablation.
Surgical ablations are usually recommended for persons who need surgery for another reason such as a heart valve repair rather than as a first choice of ablation type. Surgery involves longer healing and recovery times. Electrical mapping is most often not possible during surgery; therefore, the catheter technique can be more beneficial to many AF patients who have additional heart rhythm disorders such as a fast beating rhythm (tachycardia) called atrial flutter.
Antiarrhythmic Medications
Medications belonging to a group called antiarrhythmics (anti A rith miks) change the natural electrical properties of the heart. These medications can also help you stay in the normal rhythm; some can help change you to normal if taken during an episode. These medications change the electricity in the heart. Some medications can be given in intravenous solutions to act quickly and are used in the emergency room or hospital, if necessary, to bring the rate and rhythm under control quickly. Most of the time the medication needs to be taken by mouth regularly for several days or weeks before the change in rhythm can take place.
Direct Current Cardioversion
Electrical cardioversion is a controlled jolt of electricity (shock) delivered to the heart through the chest wall by adhesive patch electrodes or metal paddles. The shock stops all electrical activity in the heart for an instant and this allows the normal heart rhythm to take over.
Before a cardioversion, care must be taken to protect against stroke. If AF lasts longer than 48 hours, Warfarin is started to keep INR values between 2.0–3.0 for two to three weeks before the cardioversion is done. INR is a measure of clotting.
In some situations, a TEE (transesophageal echocardiogram) will be done before a cardioversion to detect any blood clots that can possibly cause a stroke. The TEE is done while a person is sedated. A tube is passed through the mouth into the passage (esophagus) that leads to the stomach. Since the tube is directly behind the heart, the test permits a good view of the inside of the heart. If the TEE does not see blood clots, the cardioversion may be done safely without the patient being put on Coumadin for two to three weeks before the procedure.
Side effects of an electrical cardioversion usually relate to skin reactions where the adhesive electrodes were placed and the electrical energy passed through to the heart. The skin can look irritated or red. If this is discomforting, ask your doctor for lotions, ointments or creams that will assist in healing.
Electrical cardioversion will not prevent AF from recurring so medications are often a necessary part of the pre-procedure routine and may need to be continued afterward for some time.
Heart Rate Control
In some patients, the path to restoring normal rhythm may not be a choice. For others, AF comes and goes infrequently and they may not be ready to select ablation therapy. Sometimes the heart will not go back to normal or the patient and doctor agree that using the stronger medications or ablation to restore normal rhythm is not the best choice. Rate control then becomes the goal. Antiarrhythmic medications, implantation of a permanent pacemaker or atrioventricular nodal (AVN) ablation combined with implantation of a permanent pacemaker may be the best options to achieve rate control in these patients.
Antiarrhythmic Medications
When a patient has only a few short-lasting episodes a year, medications are used to help racing heart rates adjust to be more in the normal range. The patient and physician may decide not to attempt to convert the AF to normal, or for some other reason such as poor general health, ablation is not a good choice. Thousands of people have AF treated with medication and do well. Atrial fibrillation is a condition arising in the upper chambers of the heart. Symptoms occur due to the fast and irregular beating of the lower chambers (ventricles) that are the source of your pulse. The chaotic electrical activity of the atria gets to the ventricles over a special electrical pathway in the heart called the atrioventricular node (AVN). Medication can be given to change how the AVN processes the chaotic signals of AF.
Medications used to slow the heart rate include beta-blockers (atenolol, toprol, metoprolol, etc.), calcium channel blockers (diltiazem, verapamil, etc.) and digoxin. Although these drugs may relieve symptoms by slowing down the heart rate, it is important to remember that they do not prevent AF from happening. There is still risk of stroke and therefore a need for a blood thinner.
Pacemakers to Control Slow Heart Rates
Medications given to control the heart rate may cause pulse slowing. Other patients may have slowing of the heart because of other conditions. A pacemaker can be implanted to help add heartbeats if there are pauses in the pulse rate.
Some patients who have severe symptoms do not respond to medications and may be helped by a procedure called an atrioventricular nodal (AVN) ablation to create a complete interruption or block of the electrical pathway between the upper (atrial) and lower (ventricular) chambers of the heart. During this catheter ablation procedure, an ablation catheter is threaded through a vein to the heart and positioned at the AV node area. Controlled energy (ablation) is delivered through the tip of this catheter to prevent the chaotic AF from traveling from the atria to the ventricles.
This will result in a state we call complete heart block and a very slow heart rate, so a permanently implanted heart pacemaker is needed to provide an adequate heart rate. This procedure is the most effective rate control treatment. This procedure causes a life-long need for a pacemaker. Progress in pacemaker design has increased the “life-like” responses of the artificial pacemaker. Most people who have had this procedure tell us their quality of life has improved because of fewer symptoms. AF is still occurring so a blood thinner is still needed.
Patients who are in AF all of the time receive a single lead (ventricular) pacemaker. Patients who are in and out of AF with regular rhythm in between the episodes will benefit most from a pacemaker that has two leads (one in the right atrium and another in the right ventricle). Some patients may benefit from a pacemaker with leads in each ventricle (right and left sides) providing synchronization of the lower chambers to help improve heart failure. Patients at risk for sudden cardiac arrest may benefit from implantable cardioverter defibrillators (ICD) that have built-in pacemakers.
If you have any interest in these therapies, you can ask us about them.