"It's a miracle," said Harris, 49, of Worcester, Montgomery County. "I feel like a million bucks."
The ability to locate and get rid of the electrical cause of a-fib has come a long way since the 1980s, when ablation was often deadly. Now, physicians have precise mapping and imaging technology, and minimally invasive ways of burning or freezing the misfiring cells.
The risks are still significant. Studies show that 3 percent to 6 percent of patients suffer setbacks such as bleeding, infection or esophageal injury. But complications that cause permanent injury or death are rare, about 1 in 1,000.
And ablation is far more effective than medication. For the best candidates - people in good overall health who have failed at least one antiarrhythmic drug and have a-fib episodes lasting less than seven days at a time - up to 85 percent are cured with ablation, although about a third require more than one procedure.
Ablation may be an option even for patients whose a-fib lasts for more than seven days, experts say. Harris had such persistent a-fib for a decade.
"There are very few things in medicine where you can say, 'We've eliminated the problem and the prognosis is excellent,' " said University of Pennsylvania electrophysiologist Francis E. Marchlinski, who treated Harris.
Fibrillation, or twitching, of the two upper heart chambers (atria) is not generally life-threatening. But a-fib patients have a five-times higher risk for stroke - clots that form in the sluggish atrial blood flow can go to the brain and block a blood vessel.
Blood-thinning medication is standard care, but Harris had a mild stroke despite taking such a regimen.
Last year, an international group of heart-rhythm specialists concluded that, although ablation can lower the risk of stroke and heart failure, "the primary justification" is to improve "a patient's quality of life."
Ablation is challenging because a-fib is one of the most complex cardiac arrhythmias, and still isn't completely understood.
Daniel Edmundowicz, chief of cardiology at Temple University Hospital, explained: "A-fib is rarely caused by an abnormal signal in just one spot. And sometimes, all you need is one residual spot [after ablation], and you're back where you started."
One early ablation procedure addressed this complexity by cutting a maze of incisions through the walls of the atria. (A much-improved "maze" procedure is still used today.)
In the late 1980s, cardiologists began using a catheter to deliver a high-voltage discharge to the fibers that send signals from the upper to lower heart chambers.
The catheter was inserted through a small incision in the groin and threaded through a blood vessel to the heart, thus avoiding the need for open-heart surgery. But the electric shock burned a devastating, nickel-size hole.
"It was an explosion in the heart," recalled Arnold Greenspon, director of the electrophysiology lab at Thomas Jefferson University. "It was a mess."
Seeking a safer approach, Greenspon helped develop a catheter that delivered microwave energy. But it lost out to radio-frequency ablation, or RFA, which works like an electrocautery device.
As ablation improved, so did technology to map and image heart activity. Now, a patient is connected to at least six monitors that include three-dimensional images and computerized navigation.
In the late 1990s, French physicians identified a crucial initial source of a-fib triggers: the spots where the four pulmonary veins open into the heart.
The newest ablation device has a balloon that fits into the opening of each pulmonary vein. A coolant fills the balloon and freezes a circle of cells.
"Theoretically, it creates much more contiguous lesions," said John Harding, director of the electrophysiology lab at Doylestown Hospital, a training center for the technology. "We've used it in many of our patients because . . . the procedures are shorter and recovery times are better."
On the drawing board, he added, are balloon catheters with lasers.
Contact Marie McCullough at 215-854-2720 or firstname.lastname@example.org.