Irregular Heartbeat: Cryoablation Stops Arrhythmias Cold

Laura DonovanIt wasn’t for lack of trying. Laura Donovan of Cedar Rapids was determined to overcome the sheer exhaustion she felt after climbing a flight of stairs or walking her dog. Laura began an exercise routine and changed her diet, figuring that losing a few pounds would help her feel better. She’d been a jogger in her younger days and typically had no problem recovering from a workout. But now it felt more difficult.

“I wasn’t getting the same results. If anything, I felt worse,” Laura says. “I was in my mid-40s, so I figured I just needed to try harder.”

But by spring 2012, it was clear that Laura’s fatigue was not a question of getting in shape—especially when a short walk to her car one day after work caused her heart to beat so fast she thought it might burst out of her chest.

Laura’s family doctor in Cedar Rapids referred her to a local cardiologist, who ordered tests and an external heart monitor to record and evaluate her heart rate and rhythm. These confirmed that Laura had atrial fibrillation, the most common type of arrhythmia. An estimated 2.7 million Americans have atrial fibrillation (also known as AFib), according to the American Heart Association.

AFib is a problem with the heart’s electrical system, where disorganized electrical signals cause the heart’s two upper chambers (the atria) to contract too quickly and irregularly. As a result, oxygen-rich blood that enters the atria isn’t pumped efficiently to the heart’s two lower chambers (the ventricles), which send the blood out to the rest of the body.

AFib symptoms—heart palpitations or a “racing” heart, fatigue, shortness of breath, light-headedness, and chest discomfort or pain—can occur frequently or only once in a while. Triggers include:

  • Caffeine
  • Strenuous exercise
  • Fatigue
  • Alcohol
  • Hormones
  • Dietary supplements
  • Stress
  • Even if the symptoms aren’t frequent or noticeable, AFib can significantly increase a person’s risk for stroke. Over time, unmanaged AFib can be one of several factors that cause heart failure, especially if the heart rhythm is abnormally fast.

For Laura, knowing she had AFib was a relief. Correcting her condition and controlling her symptoms proved to be difficult, however. Working with her Cedar Rapids heart team over the next year and a half, she underwent a series of additional tests and procedures. She also took different medications aimed at stabilizing her heart’s rhythm, but these didn’t seem to help.

After months, Laura still felt worn out. She worried whether she’d have the energy to continue her job at a local community college. Her friends and co-workers noticed a change in Laura, as well. She looked fine but lacked the zest for life she was known for.

To make matters worse, Laura, who had researched treatment options, was told during a follow-up appointment in August 2013 that she was not a candidate for AFib ablation, a catheter-based, non-surgical procedure. Ablation deadens small areas of tissue along electrical pathways of the heart in order to interrupt the heart’s abnormal electrical conduction routes that cause rhythm problems.

“Basically, they said there wasn’t much else they could do for me. I felt like I was at the end of my rope,” she says.

Finally, in December 2013, Laura called University of Iowa Heart and Vascular Center to schedule an appointment for a second opinion. She met Michael Giudici, MD, a cardiologist who is board-certified in electrophysiology—the evaluation and treatment of patients with heart rhythm disturbances.

After an examination and a review of her medical records, Giudici told Laura that she was indeed a good candidate for an ablation. Specifically, Giudici suggested a new treatment—a cryoablation balloon procedure called Arctic Front®—he had been performing since early 2013 with excellent results.

Traditionally, heart ablations have been done with extreme heat. Using radiofrequency energy, the procedure is similar to going into the heart with a tiny soldering iron and cauterizing the areas that cause the additional electrical signals that disrupt the heart’s normal rhythm.

Cryoablation, by contrast, uses extreme cold rather than heat.

“Atrial fibrillation tends to originate in these muscle sleeves on the outside of four veins (the left and right pulmonary veins, two for each lung) that bring oxygenated blood back from the lungs to the left atrium,” Giudici says. “There are tiny, electrically active fibers in these muscle sleeves that can become irritated and send out rapid impulses into the heart, which causes AFib. The key is to isolate and remove those electrical signals. The ‘cryo’ approach—using cold over heat—is a little less damaging to the surrounding tissue.”

With cryoablation, an electrophysiologist uses computer software and a special balloon catheter inserted into a blood vessel in the patient’s groin, arm, or neck to reach the heart’s left atrium and record the location of the disruptive electrical activity. Next, the balloon is inflated with coolant and placed against the opening of the vein for several minutes, sealing the vein temporarily and “freezing” the abnormal electrical signal in the vein.

“We do this two, sometimes three, times,” Giudici says. “That’s important, because it increases the likelihood of a permanent solution to the arrhythmia.”

The success rate for cryoablation is greater than 90 percent, which is “really quite remarkable for AFib ablation,” Giudici says, adding that the rate of complications has proved to be extremely low.

Laura underwent the cryoablation procedure in February 2014, and all went well. Her first words in the recovery room were “Gee, my heart is so quiet.”

“I’d forgotten what it was like not to feel your heart pounding all the time,” she says.

Today, Laura has a new job, she’s exercising again, and she’s glad when friends tell her the “old” Laura is back.

She’s amazed—and grateful—for her UI Heart and Vascular Center team, as well.

“They gave me hope, because I’d just about given up,” Laura says. “I remember telling Dr. Giudici that I might have to quit my job because of my heart. He just smiled and said, ‘Oh, that won’t be necessary—we can help you.’ Hearing him say that really meant a lot me.”

Catheter ablation is now considered a first-line treatment for AFib when medications do not correct the problem. Recent improvements in catheter balloon design and 3-D mapping software allow electrophysiologists to better pinpoint and treat the exact source of abnormal electrical activity.

“This is a great example of combining advanced technology with physician expertise and experience to offer a safe, non-surgical option for patients with atrial fibrillation,” Giudici says.

UI Heart and Vascular Center is one of a handful of centers in Iowa performing cryoablation, and one of only two centers that offer cryoablation in conjunction with a revolutionary new pressure sensing catheter that maximizes safety and accuracy. 

About AFib:

  • Disorganized electrical signals cause heart to pump inefficiently
  • Symptoms: “Racing” heart, fatigue, short of breath, light-headedness, chest discomfort
  • Triggers: Caffeine, vigorous exercise, fatigue, alcohol, hormones, diet supplements, stress
  • Increases risk of stroke or heart failure

–Winter 2014-15