Advancing technology leads to improvements in medical ablations to treat atrial fibrillation

Detailed 3D mapping of the heart’s anatomy. Tiny catheters that emit heat or cold. Sensitive instruments that pinpoint small disruptions to the body’s electrical signals.

They may sound like concepts drawn from a science fiction novel, but these advances are being used today by physicians who perform medical ablations to treat atrial fibrillation, a heart condition that affects millions of Americans. As a result, the procedure is now safer and more accurate for patients, according to M Heath Fairview Heart Care experts.

Cardiac electrophysiologists Henri Roukoz, MD and Lin Yee Chen, MD, MS perform medical ablations for atrial fibrillation at M Health Fairview University of Minnesota Medical Center alongside colleague Takumi Yamada, MD, PhD. Chen and Yamada also serve as professors in the Cardiovascular Division at University of Minnesota Medical School, and Roukoz as an associate professor.

We asked them about recent advances in atrial fibrillation treatment and how we’re bringing leading-edge care to patients in our system.

What is atrial fibrillation?

Atrial fibrillation occurs when the electrical signals that tell the heart muscle when to contract—or “beat”—begin to misfire. These rogue signals interrupt the heart’s normal rhythm by causing the heart’s upper two chambers—the atria—to fibrillate, or contract irregularly and quickly. The condition is linked to a heightened risk for serious conditions like stroke, heart failure, and dementia.

What is an ablation procedure?

The medical ablation procedure was initially developed in the late 1990s, Chen said, when doctors discovered they could use catheters delivering hot energy to isolate or destroy the source of the misfiring signals. Now, specialists can conduct the ablation by inserting more sophisticated catheters through a blood vessel in the patient’s groin and threading it into the heart.

There, an electrode at the tip of the catheter produces heat (radiofrequency) or cold energy (cryoablation) to scar a small portion of heart tissue—often near the pulmonary vein, where the rogue signals frequently originate. The scar tissue effectively blocks the pathway used by the signals that cause the fibrillation, preventing future episodes in the majority of cases.

The entire procedure takes about three hours, and typically only requires a single night’s stay in a hospital, Chen said.

Our Heart Care team performs medical ablations at three locations throughout the metro: M Health Fairview University of Minnesota Medical Center, M Health Fairview Southdale Hospital, and M Health Fairview St. John’s Hospital.

How are recent advances improving treatment?

Though this approach is not new, catheter technology has evolved in the last decade, Roukoz said. The newest generation of catheters come equipped with a saline line that continually rinses the site of the ablation and pressure sensors that inform the doctors when the catheter tip is in contact with heart tissue. They also have force sensors, which can tell doctors how much pressure they’re putting on the heart wall. These advances reduce the risk of post-procedure complications and increase accuracy, Roukoz said.

Recent developments in diagnostic imaging technology have also led to improvements in medical ablations. Doctors now use a cardiac MRI or CT scan to create a thorough, three-dimensional image of a patient’s heart anatomy before the procedure. This allows them to map out in detail their approach to the procedure. That heart map is supplemented with a special ultrasound scan just before the ablation, to ensure the patient doesn’t have any potentially risky blood clots in the heart.

Doctors also rely on real-time, 3D imaging during the procedure to help guide the catheters, Roukoz said. This imaging has also significantly improved in recent years. High-density heart mapping enables doctors to collect a lot more data points when they have the catheter in the heart. More sophisticated mapping allows us to more precisely identify and target the source of the misfiring signals, said Chen.

Cryotherapy (using cold energy to destroy the source of the abnormal signals) and high-voltage heat therapy energy have emerged as promising methods, alongside the traditional use of heat. Finally, revised protocols for blood thinner use before and after an ablation have further reduced the patient’s risk of complications.

“We’ve seen higher success rates with these advances, providing greater symptom relief for patients,” said Chen. “There is also a newer therapy called left atrial appendage closure, which closes the left atrial appendage in order to reduce the risk of stroke in people with atrial fibrillation.”

Learn more about our Heart Care program here or call 612-365-5000 to schedule an appointment.