Collaboration by cardiologists in human and veterinary medicine leads to successful repair of dog’s heart defect

Prancer has always had a lot of heart. But at a checkup on Sept. 17, a month following an uncommon procedure at the University of Florida’s Veterinary Medical Teaching Hospital to repair a congenital heart condition, the 3-year-old Springer Spaniel had additional pep in her step.

“She’s doing great,” said UF veterinary cardiologist Darcy Adin, D.V.M., who collaborated with UF pediatric cardiologist Joe Paolillo, M.D., to treat Prancer by using a device resembling a wire mesh basket to block an abnormal vessel and reroute blood through the heart in a normal manner. The device, known as an Amplatzer occluder, received federal approval for use in people in May and has only been used by a handful of veterinary institutions for treatment in dogs.

In April, Prancer’s owner — Paolillo’s colleague, UF College of Medicine cardiologist Barry Byrne, M.D., Ph.D., — noticed his dog wasn’t exercising normally and was panting frequently. He took Prancer to a local veterinarian, who heard a heart murmur. Suspecting a condition known as patent ductus arteriosus, or PDA, Byrne asked Adin to give Prancer a thorough evaluation. Adin confirmed the PDA diagnosis through an echocardiogram and chest X-rays.

“Two-thirds of dogs with PDAs will die of heart failure by two years of age,” Adin said. “When we see it, we fix it. Prancer had already beat the odds, as she was 2.5 years old when we first saw her.”

Generally, veterinarians repair PDAs in one of two ways: through open chest surgery, during which the abnormal vessel is tied off, or through coil embolization, in which a catheter inserted into a leg artery releases a coil that attracts platelets, forming a clot within the vessel to block it from within.

“In Prancer’s case, however, we felt that the PDA was too big to be coiled,” Adin said. “Dr. Byrne was still interested in pursuing something noninvasive, even though the coil was not an option. He put me in touch with Dr. Paolillo, who has done a lot of work with the Amplatzer occluder.”

The device is an ideal method for occluding large blood vessels, said Paolillo, who was able to successfully convince the device’s manufacturer, AGA Medical, to donate the occluder used in Prancer’s procedure.

“This device has been performed in animal patients in Europe for some time, and has been used successfully in animal patients both at the University of Illinois and the University of Minnesota colleges of veterinary medicine,” Adin said. “However, it’s the first time we have ever performed the procedure in animals here at UF.”

Adin and Paolillo said they feel the occluder is a reasonable alternative to surgery. The procedures cost about the same, but the cost of the occluder would make the cost of that option more expensive than the $1,500 or so pet owners would spend for surgery to correct this particular heart problem.

“It’s a complicated device to install,” Adin said. “It requires both a right and a left heart catheterization, and there’s always the risk of anesthesia. In a dog with a heart defect, the procedure takes about four hours.”

However, the biggest advantage, Adin and Paolillo said, was that Prancer went home from the hospital the next morning.

“She was here one night, gone the next morning,” Adin said. “In addition, we performed an echocardiogram that morning before she left, and it showed the PDA completely occluded.”

Paolillo was excited about having had the rare opportunity to collaborate with the UF veterinary college in a clinical case and said he would be happy to work with UF veterinarians again should similar cases arise.

“It was very unusual for a dog this size with an abnormal vessel that big to go undiagnosed for so long,” he said. “It was an unusual situation. But the main advantage to the occluder as a treatment option is that the dog was discharged the next day without a chest scar and avoiding several days in the hospital.”