An Innovative New Surgery for Dogs with Congestive Heart Failure

For the first time, a transcatheter edge-to-edge repair (TEER) of the mitral valve was performed on a dog named Rabbit at Cummings School of Veterinary Medicine's Henry and Lois Foster Hospital for Small Animals (FHSA).

Degenerative mitral valve disease is the most common heart condition in dogs. The mitral valve fails to close properly, causing leaking that impacts the efficacy of the heart. While this condition is treated with surgery in humans, the primary treatment for dogs has been medication. 

A team of doctors at Colorado State University (CSU) has worked with Hongyu Medical and Avalon Medical to make a veterinary-specific device available to perform TEER of the mitral valve on a dog, adding a new treatment option for the condition. According to Dr. Emily Karlin, assistant clinical professor in the Department of Clinical Sciences at Cummings School, one way to fix a mitral valve is through open heart surgery while the heart is stopped, a somewhat invasive but potentially curative procedure for dogs. With TEER, the surgeons can now make a small incision in the chest wall as the heart continues to beat. A catheter is inserted through the bottom of the heart to the mitral valve. With transesophageal echocardiography, the team can view the heart and mitral valve to position the device. 

The team at Colorado State reached out to other institutions, including Cummings School, to share this new method. Doctors from Cummings School's cardiology, anesthesiology, and surgery teams worked closely with CSU to learn about the TEER surgery. After the CSU team live-streamed a case, doctors from Cummings School traveled to Colorado to train in person.

"Colorado State pioneered and perfected the technique," says Dr. Rebecca Reader (she/her), an anesthesiologist at Cummings School. "Rabbit was our first case."

Rabbit is a 12-year-old, mixed-breed terrier rescue dog. Her owner, Lisa Steindler (she/her), named her Rabbit after seeing the way she hops while she runs through the fields in their home state of Vermont. Steindler became concerned about Rabbit after she inexplicably passed out one day and soon after came down with a cough that she couldn't shake.

Steindler took Rabbit to an ER vet, who diagnosed Rabbit with congestive heart failure. Her lungs were filling with fluid, making it difficult to breathe. Rabbit was put on medication, but the heart remained enlarged.

"The vast majority of cases of congestive heart failure are treated with medical management. This helps dogs feel better, but it's not treating the underlying disease," says Dr. Karlin.

A cardiologist estimated that Rabbit had three to six months to live. Their veterinarian suggested Steindler look into a new surgery at Cummings School. Steindler brought Rabbit to Foster Hospital for Small Animals for an assessment.

"We need a few things for dogs to be good candidates for this procedure," explains Dr. Karlin. "One, enough heart disease. All surgeries have risks; we wouldn't do surgery with a mild case. Two, the heart has to be the right size to put clips in. Rabbit is on the small end, but her heart is the right size. Three, the mitral valve's anatomy must be appropriate to support the clip. Her anatomy was appropriate."

Surgery was scheduled for January of last year. The CSU doctors helped Cummings School's team prepare for the surgery, a few flying to Massachusetts to assist. 

"Colorado State was wonderful, walking us through and outlining how to approach each case. We took what they do and applied it to Rabbit's case. We made some modifications, but they gave us a nice framework to set up a plan for her procedure," says Dr. Reader.

In addition to partnering with the CSU team, Dr. Karlin explains how the surgery was also a collaboration between the doctors and the owner. "Doing new things certainly has risks and complexities compared to doing what everyone's used to. We're open with owners that it's a new surgery, and we think this type of surgery will be the way of the future. It takes commitment to try something new and take the risk. Rabbit's owners knew they were going to be the first ones. It's hard to be first. We are very grateful to them for wanting to give it a try."

Dr. Karlin also acknowledged that TEER is a challenging surgery, but all went smoothly in the operating room for Rabbit. She recovered afterward for a few days at Foster Hospital for Small Animals and became "widely loved." 

Within a week, an ultrasound showed that Rabbit's heart was already smaller in size. She remains on medication. Not long after, Steindler sent the doctors a video of Rabbit back to her "rabbit-bounding" through the fields. 

"The surgery was a big success," says Steindler. "The joy my husband and I receive from her is beyond words. We are so grateful that she has the opportunity to live longer because of this operation and the team at Tufts. Everybody at Cummings School has been unbelievably wonderful to us and Rabbit."

Cummings School's team has since performed 15 TEER surgeries on dogs. While TEER surgery does have some inherent risks, in most cases, dogs recover well, breathing better without coughing and gaining strength back, according to Dr. Karlin. "Owners commonly report a perceptive difference in their dog's quality of life."

"This is a really novel procedure that has the potential to help a lot of pets," adds Dr. Reader. "We keep honing and perfecting the technique. It was a big group effort between cardiology, anesthesiology, and surgery—everyone worked nicely together to bring this procedure to Tufts [Cummings School]. I am so grateful to have been included on the team bringing it in."