Millions of Americans live with a common abnormal heart rhythm known as atrial fibrillation (a-fib), but new research suggests that exercise might ease the severity of the condition.
When folks with a-fib participated in a six-month exercise program, they were able to maintain a normal heart rhythm and had less severe symptoms than those who only received information about the benefits of exercise. The benefits lasted for at least one year.
"Participating in a structured exercise program for up to 3.5 hours per week can reduce the likelihood of ongoing episodes of arrhythmia and decrease the severity of a-fib-related symptoms, such as palpitations and shortness of breath," said study author Adrian Elliott, a physiologist and research scientist at the University of Adelaide in Australia.
A-fib occurs when the upper chambers of the heart quiver chaotically, causing a fast and irregular heartbeat. Symptoms may include heart palpitations, breathlessness, dizziness and/or extreme fatigue. When left untreated, a-fib dramatically increases risk for stroke and heart failure.
For the study, 60 people with a-fib participated in a six-month exercise regimen that included supervised exercise each week for three months and then every two weeks for the remaining three months. They also received an individualized weekly plan to follow at home. The goal was to work up to 3.5 hours of aerobic exercise each week. Another 60 people received exercise advice and were asked to engage in 150 minutes of physical activity every week.
Everyone in the study continued their usual a-fib medications. A-fib is typically treated with medication to lower the risk for stroke and/or drugs that control heart rate or rhythm. Sometimes a procedure known as ablation is needed. During ablation, your doctor creates small scars in the area of your heart that is causing the irregular heartbeat using radiofrequency energy.
After one year, the a-fib recurrence rate was 60% in the exercise group, compared to 80% in the advice-only group. In the study, recurrence was defined as having an a-fib episode that lasted longer than 30 seconds, undergoing an ablation procedure, or requiring ongoing anti-arrhythmic drug therapy.
People in the exercise group also had fewer heart palpations and less shortness of breath and fatigue at one year compared to those folks in the advice-only group.
"Our findings do suggest that patients who participate in regular aerobic exercise may be able to reduce the need for rhythm control therapy," Elliott said.
Exactly how exercise helps control heart rhythm is not fully understood yet, he said.
The findings were presented Monday at the European Society of Cardiology's annual meeting online. Research presented at meetings is typically considered preliminary until published in a peer-reviewed journal.
Outside experts agreed that exercise is an important part of a-fib treatment.
"This is a very interesting and important study for patients with a history of atrial fibrillation, the most common heart arrhythmia," said Dr. Deepak Bhatt, executive director of interventional cardiovascular programs at Brigham and Women's Hospital Heart and Vascular Center in Boston.
"Physical activity and exercise appear to decrease atrial fibrillation, including the severity of symptoms," Bhatt said. "So, like for most things in cardiovascular medicine, exercise is good for you."
Dr. Laurence Epstein agreed. He is the system director of electrophysiology at Northwell Health's Sandra Atlas Bass Heart Hospital in Manhasset, N.Y.
Epstein said many factors are effective in managing a-fib, including "weight loss [if needed], smoking cessation, treatment of sleep apnea and exercise, often along with medication or ablation." Sleep apnea — or pauses in breathing during sleep — can trigger a-fib episodes, he noted.
When a person does all of these things, the odds that a-fib treatment is successful go way up, Epstein said.
Still, he cautioned that exercise is helpful — until it's not. Too much intense exercise can increase the risk for a-fib, he added.
Epstein's advice? "Moderation is always the key." Aim for 3.5 hours a week of cardiovascular and strength training exercise. And "if you have any underlying condition, it's important to check in with your doctor first."