Normally, the heart’s rhythm is controlled by electrical impulses generated by the heart’s pacemaker cells. These impulses travel through the atria to the AV node, a rhythmic mechanism that causes the ventricles to contract after the atria contract. (The delay gives the atria time to fill the ventricles with blood, which the ventricles then pump to the body.)
During normal heart rhythm (usually 60 to 100 beats per minute), each atrial beat conducts in a 1-to-1 ratio with the main pumping chambers, or ventricles. Atrial fibrillation occurs when an extra electrical signal emerges – usually from the pulmonary veins, which bring oxygenated blood from the lungs to the left atrium. The rapid atrial rhythm (up to 500 beats per minute) corresponds to an irregular ventricular rhythm of about 110-140 beats per minute.
This extra, premature signal causes electrical impulses to rotate in a circle, a wavelet, within the left atrium. AFib results from multiple wavelets rotating randomly around the left atrium. When this happens, the atrium no longer contracts and the AV node gets bombarded by random electrical signals, which cause the left ventricle to beat rapidly and irregularly.
Symptoms of atrial fibrillation may range from no symptoms at all to mild to severe manifestations of the following:
- Palpitations— sensations of a racing, irregular heartbeat or a flip-flopping in your chest
- Lightheadedness and fainting
- Shortness of breath
- Chest pain
The decrease in blood flow from the heart is what leads to these symptoms.
In some cases, atrial fibrillation appears in patients without other diseases, but the following conditions are known to increase your risk of developing atrial fibrillation:
- Advancing age
- Heart diseases (Coronary artery disease, valvular disease, heart enlargement and weakening, congestive heart failure)
- High blood pressure (especially when not well controlled)
- Chronic conditions (Diabetes, lung disease, sleep apnea and more)
- Metabolic imbalances (such as overactive thyroid)
- Alcohol consumption (especially binge drinking)
- Family history
While atrial fibrillation itself is not life-threatening, when left untreated, it can lead to complications such as stroke and heart failure (described below). Atrial fibrillation also reduces the quality of life for patients who experience symptoms that are severe enough to disrupt their day-to-day activities. Others suffer from anxiety over the unpredictability of their condition, and the fear that can accompany atrial fibrillation episodes.
Because atrial fibrillation makes it more difficult for your heart to pump blood effectively, blood may pool in your left atrium, where it can form clots. If a blood clot is pumped out of your heart and into the circulatory system, it may travel to the brain and block a blood vessel there, causing stroke. Atrial fibrillation increases the risk that a patient may suffer stroke by nearly five times, and strokes related to atrial fibrillation are nearly twice as likely to be fatal or disabling as strokes unrelated to atrial fibrillation.
With atrial fibrillation, the heart beats at a rapid rate but is inefficient at pumping blood. The heart muscle becomes stressed and overworked, and it eventually weakens, further decreasing its ability to pump blood. If this process continues without intervention over a period of weeks or months, eventually the heart becomes unable to circulate enough blood to meet the body’s needs.
Your physician can diagnose atrial fibrillation by recording the electrical rhythm with an electrocardiogram (ECG) machine or an ambulatory heart monitor. Your atrial fibrillation assessment will take place through the
UW Electrophysiology Service, which has been providing state-of-the-art heart rhythm care for more than 30 years.
You will also receive a complete history and physical exam, along with blood tests (including thyroid-function tests) and cardiac imaging tests such as an echocardiogram and a cardiac MRI.
Your physician will work with you to decide on the best treatment for your atrial fibrillation. Treatment recommendations will vary depending upon factors such as the severity of your atrial fibrillation, the length of time that you have had it, any underlying medical issues you may have, and your own personal goals.
3D Imaging Examples
Our patients are treated compassionately in a collaborative setting by a multidisciplinary team. The physicians include national recognized experts in atrial fibrillation ablation, cardiac MRI imaging, surgical treatment of AFib, which offers you access to the newest technologies that often aren’t available elsewhere in the Northwest.
After your diagnostic work up is complete, your physician will discuss your treatment plan that may include medications, non-invasive or invasive procedures.
These include medications for treating and preventing blood clots and other medications to control the rhythm of the heart.
Blood clot medications
Medications that treat and prevent blood clots are known as blood thinners (anticoagulants). Blood thinners work by decreasing the blood’s ability to clot, thereby preventing the formation of potentially harmful blood clots.
Heart rhythm medications
Medications to slow the heart rate fall into three categories:
Beta blockers: Beta blockers help to slow the heart rate by blocking the effect of the hormone, adrenaline.
Calcium channel blockers: Calcium channel blockers work by interfering with the calcium channels in heart muscle cells—reducing the strength of the muscle cell’s contraction, and thereby slowing the heart rate.
Digoxin: Digoxin slows the heart rate by blocking electrical impulses. It also strengthens ventricular contractions so that the heart is able to pump more blood with each beat.
Physicians at UW Medical Center are the first in the region to use cardiac magnetic resonance imaging (MRI) to select the most appropriate atrial fibrillation strategy for your specific circumstances. MRI scans work better than fluoroscopy and CAT scans to reveal tissue that has been damaged by atrial fibrillation. Physicians review these scans to quantify the degree of fibrosis (hardened fibrotic tissue) in the heart. Analyzing the location, depth and degree of fibrosis allows physicians to recommend the strategy that will work best for your unique circumstances—radiofrequency or cryo-balloon ablation, left atrial appendage closure, the surgical maze procedure or management via medication and lifestyle change.
For many years, doctors have tried to pinpoint those characteristics that predict success with the ablation procedure so that individuals may receive a personalized recommendation. UW Medical Center is the first in the region to do so.
The image below uses color to illustrate how the MRI reveals fibrotic tissue. The tissue that is highlighted blue is healthy tissue while the tissue that is highlighted green represents diseased (fibrotic) tissue. Atrial fibrosis quantification is a non-invasive marker that can be used to predict the success of ablation (the more diseased tissue there is, the less likely that the ablation procedure will succeed).
Heart MRI Example
The UW Medicine Atrial Fibrillation Program offers a comprehensive and personalized approach to the evaluation and management of the individual patient with atrial fibrillation (AFib). Our consultation addresses the various aspects of AFib management including risk assessment and treatment options to reduce AF-related stroke, as well as extensive options for rhythm management of electrical abnormalities.
Referring providers have direct access to Nazem Akoum, M.D., Director of UW Medicine Atrial Fibrillation Program, (firstname.lastname@example.org, 206.543.3269) to discuss a specific patient prior to referral.
The AFib Consult Clinic brings together clinicians from many disciplines to provide the best care to patients, promoting the excellence that UW Medicine is known for. Our physician team includes general cardiologists, cardiac electrophysiologists (EP), and access to interventional cardiologists and cardiac surgeons as needed. We manage AFib by offering state-of-the-art treatments that address both correction of arrhythmia and reduction of AFib-related risk of stroke.
Our center is the only one in the region to offer atrial fibrosis quantification through cardiac magnetic resonance imaging and integrate this in clinical decision making. Atrial fibrosis quantification is a non-invasive marker and guiding predictor of stroke risk and choosing the best ablation option.
UWMC is also one of the busiest in the region in radiofrequency and cryo-balloon ablation, and surgical maze for rhythm management of AFib, as well as percutaneous left atrial appendage (LAA) closure to reduce stroke risk as an alternative to anti-coagulation in specific cases.
We provide the most comprehensive care and partner closely with the patient and referring providers to achieve the treatment goals. We have five clinic locations throughout the area to offer patients convenience and greater access.
We encourage starting the discussion about treatment options for AFib early in the disease process. However, patients at any stage, including those with medical co-morbidities and in need of overall consultation for complex management, are also appropriate for this clinic. Based on the patient’s current condition and history, many treatment options and strategies may be offered, from medical to catheter-based therapies, as well as possible referral for surgical treatment.
If patients have not yet been seen by a cardiologist and are early in their diagnosis and management of AFib, they will be seen by one of our cardiologists who will work closely with the referring provider. The evaluation will consist of testing and workup depending on what has already been completed. Certain diagnostic tests can be completed through the primary care or general cardiology physician, while more complex tests will be done by our providers at one of our facilities listed below. If patients already have a cardiologist who is seeking advanced or a complex care consultation, then the initial visit will be with one of our electrophysiologists.
Service level can be limited to a one-time consultation or it can extend to subsequent treatment, as needed, for care management assistance or procedure. The latter will be performed at UW Medical Center or Northwest Hospital. Patients will have regularly scheduled follow-up appointments with our team after any procedure is performed.
It is very important to us that patients maintain a close relationship with you, the referring provider, and we will reaffirm this at every encounter. No matter what the level of service being sought, we will work closely with you on a treatment plan that is acceptable to both you and your patients.
All patients will receive clinical evaluations first. In addition, patients will be offered a discussion of research studies that may be appropriate for them. Choosing to participate in or to decline research will not affect patients’ clinical care and treatment.
To refer a patient or speak with any of the AFib Consult Clinic physicians, call 1.866.UWHEART (894.3278); fax 206.598.7451.
If you have any other questions or need further information, you may also contact the Physician Liaison at
email@example.com or 206.598.3473.
- Appointments: UW Medicine Contact Center, 206.520.5000
- Consultations (with an attending cardiologist): Medcon, 800.326.5300
- Referrals: 866.UWHEART (866.894.3278) / Fax: 206.598.7451
- Physician Liaison: 206.598.3473
UW Cardiology Faculty
UWMC Cardiovascular Clinic
1959 NE Pacific St, Seattle, WA 98195
Phone: 206.598.4300 Fax: 206.598.7451
Nazem Akoum, M.D.
Kris Patton, M.D.
Jeanne Poole, M.D.
Jordan Prutkin, M.D.
Melissa Robinson, M.D.
UW Medicine RHC – Eastside Specialty Center
1700 116th Ave NE, Bellevue, WA 98004
Phone: 425.646.7777 Fax 206.520.2249
Jordan Prutkin, M.D.
Melissa Robinson, M.D.
Harborview Cardiology Clinic
325 9th Ave., Seattle, WA 98104
Phone: 206.744.3475 Fax: 206.744.6426
Nazem Akoum, M.D.
UW Medicine RHC – Edmonds
21701 76th Ave. W., Edmonds, WA 98026
Phone: 425.774.8251 Fax: 425.775.1063
Nazem Akoum, M.D.