Catheter ablation of cardiac arrhythmias is a relatively common procedure for humans—nearly 520,000 were performed in the U.S. from 2000 to 2013, with more being performed annually later in the study.

But cardiac ablation remains exceedingly rare for dogs, with only two veterinary hospitals in America offering the procedure, according to an article in the Cornell Chronicle. The publication detailed how veterinarians from three countries joined forces at Cornell University Hospital for Animals (CUHA) to correct an arrhythmia for Rex, a 6-month-old German Shepherd.

Rex’s owners originally thought he was just an incredibly calm puppy, but they later discovered his heart problem when he became violently ill in December 2017. It turns out the source of his low energy had been the arrhythmia, caused by a bundle of tissue in Rex’s heart.

Once Rex arrived at CUHA in Ithaca, New York, the cardiology team controlled his tachycardia and waited for their colleague Roberto Santilli, DVM, PhD, to arrive from Italy, his home country. Santilli, according to the article, is one of the few veterinarians in the world who can perform the catheter component of the ablation, which requires threading a catheter through the jugular and femoral veins to the appropriate portion of the heart.

As Santilli guided the catheters, his French colleague Romain Pariaut—chief of cardiology at CUHA—signaled timed blasts to break up the accessory pathway without damaging the nearby atrioventricular node.  

Rex came running down the hallway to greet his owner six hours later and went home the next day. A few months and a couple of checkups later, his heart is stronger than ever.

“Now all he does is run,” said Karen Silverman, the owner. “He finally has the energy to play.”

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