When she answered her on-call phone one day last May, NC State cardiology resident Abby Laws heard, “We have your patient Alex in the ER,” and instinctively knew that the cat client she adored had developed a blood clot and undoubtedly was in bad shape.

At just a year old, Alex had been diagnosed with hypertrophic obstructive cardiomyopathy and prescribed the anticoagulant clopidogrel to decrease the risk that his sluggish blood would form dangerous clots. When Laws started her residency at the NC State Veterinary Hospital in 2024, she became the cat’s admirer and provider of periodic checkups.

After rushing to the ER, Laws stepped into a sad and stressful scene — but also into the middle of a one-stop marvel of medicine. The NC State College of Veterinary Medicine is where research ideas are generated, tested, refined, studied in clinical trials and then offered as life-changing therapeutics to hospital clients — all in one place.

Alex’s owner, Anlan, is a Duke University graduate student who had battled nerve-shredding traffic between Durham and Raleigh to get her cherished and suffering cat to the hospital. Before calling Laws, the emergency team had diagnosed a feline arterial thromboembolism — a severe blood clot that travels to the rear legs, causing extreme pain, hind limb paralysis and often death — and administered pain medication.

“He had vomited, lost the use of his hindlimbs, and he was vocalizing, sort of a classic presentation for a cat with an ATE,” says Laws, a North Carolina native who earned her bachelor’s and DVM at NC State. “He was just really upset. It was essentially not good, not good. The literature suggests that only about 30% can survive this with varying levels of functionality.” 

At NC State, however, cats like Alex are the focus of innovative research into the confounding questions regarding cats and clots. 

About 15% of all cats develop a heart condition called hypertrophic cardiomyopathy, which causes the left atrium to enlarge and blood flow to slow, potentially leading to clot formation. Dr. Ronald Li, associate professor of emergency and critical care at NC State, says about 15% of cats with HCM will develop a feline arterial thromboembolism.

Award-Winning Feline Researchers

Li and Dr. Joshua Stern, associate dean for research and graduate studies at the NC State College of Veterinary Medicine, are nationwide leaders in feline cardiology research. Both researchers, Stern in 2024 and Li in 2025, have received the American Veterinary Medical Foundation’s Career Achievement in Feline Research Award.

Their investigation into why some cats taking clopidogrel still develop blood clots, as Alex did, found that genetic mutations are responsible about 20% of the time. The researchers developed a simple genetic test, available through the NC State Veterinary Genetics Laboratory, that now can tell veterinarians which cats with HCM are resistant to clopidogrel. 

If the test had been available for Alex in 2023, doctors would have found that he had a genetic mutation — a fact discovered during his five-day hospitalization at NC State.

“When we get cats that are on clopidogrel, if we see any evidence on their echo that they still have slow or stagnant blood flow, we submit their blood to Dr. Li’s laboratory  for the genetic test,” Laws says. “We’re getting a lot of patients that are positive, homozygous or heterozygous, for the gene mutation, and we’re starting those patients on additional anticoagulant medication to hopefully prevent these horrible ATEs from happening to others.”

In his ongoing studies, Li wants to better quantify how common this mutation is in cats that develop blood clots despite being treated with clopidogrel. Understanding this would help researchers develop new therapeutic strategies to protect cats with HCM from blood clots.

“We are conducting a study to test the behaviors of platelets in cats that are positive for this mutation,” Li says. “We want to know if there are alternative pathways that we can target. But what should we do with this information? That’s going to take a little bit longer.”

Li plans to conduct future clinical trials to see whether increased dosages or different  types of anticoagulants would improve the outcomes for cats with a genetic mutation. 

“Or can we look at another drug that is a candidate?” he says. “But that’s not the end, right? We have to do trials to see if it actually has a benefit in the population, so it’s a multi-step process.”

Euthanasia on the Table

Alex might have been late to the first breakthrough, but he’s right on time for the second — and gets to contribute to it.

“Alex is a perfect example of this work because he was on this medication already and still formed a life-threatening clot, and he presented at the ER in a scenario where many owners would have stopped right there,” says Laws, who praises Anlan’s dedication. “Now, he is on that additional anticoagulant to minimize the chances of this ever happening again.”

He’s a miracle cat in Laws’ mind. On the fourth day of Alex’s hospitalization, she prepared Anlan for the possibility of euthanasia because he wasn’t eating, he was barely mobile and his kidney function was stressed. 

“He had lived a year and a half with this horrible congenital heart disease, and then he had his ATE, and at that point, prognosis, by all statistics, was really, really poor,” she says. “He has just exceeded all of the odds you could come up with and hopefully continues to do so.”

Anlan says she feels lucky to have met a doctor who so genuinely cared about Alex, her little chewy mochi. 

“He would not have made it this far without her, and I’m grateful for everything she has done,” Anlan says. “Dr. Laws quickly noticed the signs that Alex was improving and decided to keep him one more day, when otherwise he might have been put down. During the time he was paralyzed, she checked in with me daily and gave me detailed guidance on his recovery and how to care for him at home.”

Alex has now recovered fully from his arterial thromboembolism. Anlan recently sent Laws a video of the cat jumping from the kitchen counter to the table. 

“There was a question before where we didn’t know if he was ever going to use his back legs again, and now he’s jumping, and he’s playing with his sister and doing all these crazy things,” Laws says. “Cats always defy every medical statistic you try to put on them, and so I think he’s just doing exactly that. He’s living his best life.”