Staying on beat

Tara, a schnauzer dog, relaxes on a dog bed
Tara, a 12-year-old schnauzer, is one of nearly two dozen dogs that undergo pacemaker implantation surgeries each year at the Veterinary Medical Center.

Richard Berg would watch with dread each time his 12-year-old schnauzer Tara would begin to wobble. Soon after the teetering began, she would faint.

“It was so hard to see,” he says. “I thought for sure I was going to lose her.”

As it turned out, Tara’s heart was the culprit. A trip to the veterinarian revealed a diagnosis of sick sinus syndrome (SSS), a disorder that occurs when the heart’s sinus node—the part of the heart that regulates its rhythm—no longer functions properly.

In Tara’s case, her SSS was treated through the implantation of a pacemaker, a medical device that delivers electrical signals to restore a normal heartbeat.

About 20 dogs receive pacemakers each year at the University of Minnesota Veterinary Medical Center (VMC). It’s a treatment with roots in Minnesota. Electrical engineer and U of M alum Earl E. Bakken invented the first battery-operated, wearable pacemaker in 1957 in Minneapolis. Bakken is the co-founder of Medtronic, which now donates hundreds of pacemakers each year for veterinary procedures through the CanPacers program—including Tara’s. 

Following Bakken’s breakthrough, the first implantable pacemaker procedure in a human was performed in 1958. Ten years later, the technology was used to treat an abnormal heart rhythm in a dog at the University of Pennsylvania. Since then, pacemaker placement by veterinarians has become more commonplace.

Christopher Stauthammer, head of the VMC’s Cardiology Service, credits a pacemaker case in veterinary school as part of the inspiration for his pursuit of a cardiology specialty.

“It was Henry, a cocker spaniel who was experiencing passing-out symptoms,” he recalls. “The dog needed a pacemaker, which was surgically implanted that same day. The passing-out episodes resolved, and Henry was discharged the following day.”

Just like humans, some dogs have abnormal heart rhythms—also called arrhythmias. These dogs have a heartbeat that is occasionally too strong or too weak, too slow or too fast, or that skips a beat altogether. While some dogs show few symptoms, others may begin to sleep more, show intolerance to exercise, appear weak or lethargic, collapse or stumble, or, perhaps, vomit and lose their appetite.

A dog’s owner may not pick up on a pet’s symptoms or may attribute changes to the pet’s old age—the arrhythmia remaining undiagnosed. While not all arrhythmias require treatment, others may be life-threatening.

While the type of heart condition it treats may vary, the implantation of a pacemaker has become a “relatively routine” procedure, according to Stauthammer.

“The process involves a team of anesthesiologists, cardiologists, and amazing veterinary techs, and it takes about two hours to perform,” he says. 

If no complications arise, a dog can go home after a day or two and return to regular activities after six weeks.

One aspect of Stauthammer’s job that makes it so rewarding is the ability to improve survival times in animals by implanting pacemakers.

Seeing smiling owners reporting improved energy levels and happier pets after the procedure makes Stauthammer and the VMC team proud of every success story.

This story was adapted from Profiles, a magazine of the College of Veterinary Medicine.