For Karen Cortellino, Sophie the boxer is an irreplaceable member of her household. She was the “flower dog” at the wedding of Cortellino’s daughter. She was an honored guest at her son’s college graduation. And she was the loyal and gentle companion to Cortellino’s mother as she faced her days in hospice care, at home.
“Sophie has been part of our family since the day we adopted her,” Cortellino said.
So when the almost 9-year-old boxer collapsed without warning and fell unconscious at her New Jersey veterinarian’s office last July, Cortellino rushed her to a veterinary cardiologist with the kind of urgency she’d provide any family member.
The news wasn’t good.
Sophie was diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC), a form of heart disease that afflicts people as well as dogs, especially boxers. Patients of either species are at risk for arrhythmias, or abnormal heart rhythms. If severe, they can cause sudden death.
“The cardiologist told us the standard treatment for dogs is medication, but that Sophie would still be at greater risk for sudden death,” said Cortellino.
Cortellino, herself a physician, began researching other ways to help Sophie. And that’s how the dog wound up at Penn’s School of Veterinary Medicine, where she was the first beneficiary of a pilot program that uses a human-standard ARVC procedure to treat AVRC in boxers. Penn Vet’s partner in the program is the Translational Cardiac Electrophysiology Center at Penn’s Perelman School of Medicine, which researched and pioneered what is now the standard of ARVC treatment in humans: catheter ablation.
The procedure uses radiofrequency energy to destroy a small area of defective heart tissue that in Sophie’s case was causing rapid heartbeats. Burning away the tissue prevents abnormal heartbeats and helps restore a regular rhythm.
“The wonderful thing is, the entire ablation procedure is done with catheters inserted through blood vessels and guided up to the heart,” said Cory Tschabrunn, director of Penn’s translational electrophysiology lab. “We don’t even need to make a large incision. We just use a needle to gain access to the vessels.”
Usually, human patients are up and walking around in a day or two, he said.
Funded by two grants, the pilot between Penn Vet and Penn Medicine not only uses ablation to treat boxers with AVRC but employs sophisticated cardiac mapping to learn more about the deadly disease in the breed.
Ablation in dogs is uncommon. The procedure has been successfully performed on dogs in just a few veterinarian centers around the world and for heart problems other than ARVC. At the time of Sophie’s procedure, there was no published record of successful ablation therapy for boxers with ARVC, said Anna Gelzer, the Penn Vet cardiologist spearheading the project.
“This is a life-threatening disease,” Gelzer said. In just 33 months, Penn Vet had seen 14 boxers, one of the United States’ most popular breeds, with ARVC, Gelzer said, but the available treatment has not been very satisfactory. Arrhythmias, or irregular heart rates, have been known to break through the medications used, she said.
Defibrillators, an alternative for humans, have not been an option for dogs.
“Compared to a human, a dog has much more immediate changes in heart rate just from being awoken by a bird flying by the window, or the doorbell ringing, or they get excited because they hear the leash clinking in their owner’s hand,” Gelzer explained.
“Those abrupt changes in heart rate can look like abnormal rhythms to defibrillators designed for people. They can discharge when they’re not supposed to. That’s devastating because it causes intensive discomfort if the [dog] is conscious and not having arrhythmias.”
After performing an ablation for a different cardiac problem on another dog, Gelzer and the electrophysiology team received funding to pilot the use of the procedure on boxers. The partners were looking for their first ARVC boxer patient when Gelzer heard from Cortellino, seeking help for Sophie.
“The stars were aligned just right,” said Gelzer.
Cortellino admitted to some trepidation.
“The newness on a dog was scary,” Cortellino said. “But with the expertise of Penn’s veterinary school with Dr. Gelzer at the helm, we were comfortable. We understood the risks. We understood the benefits, and we made the decision to go ahead.”
The big day was Aug. 28.
Sophie’s ablation was done not at Penn Vet but at Penn’s medical school, at the Smilow Translational Research Center, where Tschabrunn’s laboratory and all that cutting-edge equipment resides.
On the day of the procedure, Gelzer and Alex Crooks, a Penn Vet resident, assisted Tschabrunn, whose experience allowed him to position the mapping and ablation catheters inside Sophie’s heart and create a sort of roadmap of the heart’s electrical activity. That identified where the dangerous arrhythmia was coming from in Sophie’s heart. Once that was located, Tschabrunn demonstrated for his veterinary partners how the ablation catheter delivers radiofrequency energy to eliminate the diseased area.
The procedure took several hours.
“They kept us informed by text message the whole day,” said Cortellino.
By the next day, Sophie was ready to go home — happy to see her people, but still a bit tired and a little sore, but only for a few days.
“She’s recovered 100%,” Cortellino said.
Maybe even a little too much. Last fall, just a few months after the ablation, the still-a-puppy-at-heart boxer decided to eat some rubber gloves, a couple of months after the ablation. The gloves had to be removed by surgery, but Sophie was soon — again — good to go.
“We are very happy we did the [ablation] procedure,” Cortellino said. “While it was a risk, we’re hopeful it will give us many more happy years with Sophie and help other dogs with ARVC in the future.”
In August, the pilot team was able to perform the ablation procedure on a second boxer, a dog named Ernie, whose owner lives in Flourtown. Gelzer said the team is still looking for additional boxers with ARVC who would be appropriate candidates for the study. Beyond saving the dogs’ lives, their goal is also, through the mapping and comparison to ARVC in human patients, to gain more insight into the disease itself.
While ARVC is believed to be genetic in origin, the median age of its often-abrupt manifestation in dogs is about 6 years of age — or adult-onset, like its human sufferers, according to Gelzer.
Meanwhile, Penn Vet is also currently exploring screening procedures and other therapies for ARVC.
Said Gelzer, “There’s still so much to learn.”