TOWARDS A DRUG-FREE CURE FOR ATRIAL FIBRILLATION
More than 2.2 million Americans have some form of atrial fibrillation (afib), making it the most common type of heart rhythm abnormality. We expect its prevalence to double in the next 30-40 years.
Afib occurs when the upper chambers of the heart—the atria—beat rapidly and irregularly. Symptoms of afib include fatigue, shortness of breath, palpitations, difficulty exercising, chest discomfort, and light headedness or fainting.
The irregular beating can cause blood to stagnate in the heart’s chambers, increasing the risk of blood clots from the heart causing a stroke. People with afib are, on the average, five times more likely to have a stroke than those without the condition. Unfortunately, some patients don’t know they have afib until they are diagnosed in the emergency room after suffering a stroke.
The rise in obesity is contributing to the increasing incidence of afib. The presence of fat around the heart causes a local inflammatory process which can disrupt the heart’s ability to beat normally and lead to afib. Additionally, obesity can cause sleep-disordered breathing (sleep apnea) and/or high blood pressure, syndromes associated with afib.
Because antifibrillatory drugs may trigger a very slow heart rate, treatment sometimes involves both implanting a pacemaker (to prevent a slow heart rate) and taking drugs. Another treatment, called cardioversion, basically “shocks” the heart into beating normally, although regular rhythm is subsequently maintained in only 25% of patients at one year in the absence of taking an antiarrhythmic drug. Unfortunately, medications only improve the likelihood of maintaining regular rhythm after cardioversion to about 50% at one year, and most of the drugs have unpleasant side effects.
In my more than 25 years of practice, I have not found a treatment more effective than a procedure called catheter ablation. A successful ablation eliminates the need for antifibrillatory drugs as well as consideration of pacemaker implantation.
Catheter ablation involves electrically scarring the tissue that triggers the irregular heartbeat. The procedure is performed while the patient is asleep, under anesthesia.
We insert thin electrical catheters into the heart via upper thigh veins and pass “radiofrequency” energy through the catheters, which causes the formation of very small scars in the lining of the heart chamber.
Some patients can go home the same day, after they lie down for several hours. Others must be observed overnight and can go home the following day. Lutheran General Hospital has one of the highest volume ablation programs in the Chicago area. It still amazes me to see patients come into our lab in atrial fibrillation and leave with a regular heartbeat after the procedure.
Even though we have found a very effective treatment for afib, our efforts to improve it continue. Lutheran General Hospital is beginning a research project that will help determine the impact of using a newly developed catheter in the ablation procedure. Our hope is to further improve the outcomes for patients with atrial fibrillation.
Scott M. Miller, M.D., F.A.C.C., is Director Cardiac Electrophysiologt at Advocate Lutheran General Hospital. He was named one of Chicago Magazine’s Top Doctors 2012 in Cardiac Electrophysiology.