A Maltese puppy named Carter became the first dog to undergo a new procedure at Washington State University that will provide a safer treatment option for the tiniest of patients diagnosed with patent ductus arteriosus or PDA, a common and deadly congenital heart defect.
The new procedure, which has been performed at only a handful of facilities in the country, is specifically designed for dogs under 6 pounds. It has a far faster recovery time than other treatments for PDA, which can be life-threatening and requires veterinarians to close a blood vessel in the heart. Carter’s procedure took less than two hours, and he was already showing significant improvement in activity and heart function the following day.
At just 4.5 pounds, patients like Carter typically would have a thoracotomy, or open chest surgery, to correct the defect, however, the procedure is more invasive and typically requires a longer recovery period.
At just 4.5 pounds, patients like Carter typically would have a thoracotomy, or open chest surgery, to correct PDA, however, the procedure is more invasive and typically requires a longer recovery period.
“The day after his surgery, Carter was already brighter and more active than before. This procedure will allow him to live a normal, happy life,” said Dr. Anna Golden, a cardiology resident in WSU’s College of Veterinary Medicine’s Veterinary Teaching Hospital who performed the new procedure along fellow resident Dr. Kya Fedora-Degarmo and cardiologist Dr. Ryan Baumwart. “It is pretty awesome to be able to offer a minimally invasive option for these dogs instead of them having to have a thoracotomy.”
PDA occurs when a critical blood vessel, the ductus arteriosus, fails to close after birth. This defect forces the heart to work harder to pump blood, leading to potentially life-threatening complications. A PDA is typically identified by a heart murmur during routine veterinary check-ups, as was the case for Carter at just 6 weeks old. Without treatment, PDA is often fatal, but the condition can be cured with surgery if caught early.
For dogs that are large enough, typically those weighing more than 6 pounds, cardiologists at WSU have offered two types of procedures to treat the condition: an open-chest surgery known as thoracotomy or a minimally invasive catheter-based procedure.
While effective, thoracotomy is more invasive, painful and carries more risks, including fatal hemorrhage. Recovery from thoracotomy is also longer and requires more time in the hospital.
The minimally invasive option involves inserting a catheter through the femoral artery in the leg and guiding it to the heart using continuous X-ray imaging. A small device is maneuvered through the tube and used to close the PDA. This method is less painful, and patients typically go home the next day. The procedure is more challenging on dogs that weigh less than 6 pounds due to the smaller size of the blood vessels in the legs that are used to place catheters.
The new procedure is similar, although the catheter is inserted into the jugular vein — which is larger than the femoral artery — through a small incision on the neck and a different route is taken to the heart.
Dr. Anna Golden, left, a veterinary resident in cardiology at the Veterinary Teaching Hospital in the College of Veterinary Medicine, poses for a photo with fourth-year veterinary medicine student Ashalynn Bilton-Smith, right, while holding Carter, a Maltese puppy (photo by College of Veterinary Medicine/Ted S. Warren).
“Carter was an ideal candidate for this minimally invasive procedure,” Golden said. “We were able to get him in and out of the hospital within 24 hours, compared to the longer hospitalization required for open-chest surgery.”
Although any breed can be affected by PDA, the condition does appear to have a heritable component. Carter’s owner agreed to participate in a DNA collection effort led by WSU to help better understand how PDA is passed from generation to generation. The owner also said Carter will be neutered so he doesn’t pass the trait to offspring, and his mother will be spayed to prevent further breeding.