Canine Pacemakers—Giving Patients a New Leash on Life

Canine Pacemakers—Giving Patients a New Leash on Life

It is estimated 10 percent of all dogs have heart disease. As dogs age, the prevalence of heart disease may reach more than 60 percent, said Dr. Mandi Kleman.

As dog parents we are constantly worrying about the health of our dogs. We are reminded of their aging by slightly graying muzzles, a slowed gait and an increase in sleep.  What we don’t realize is that sometimes symptoms that we pass off as the ailments of aging can potentially be symptoms of an underlying heart condition.

“Owners may believe [dogs are] just slowing down or becoming lazy, when in actuality they don’t have enough energy because their heart rate is too slow due to heart block,” said Dr. Kleman, a Cardiologist at Cornell University Veterinary Specialists (CUVS).

Complete Heart Block and Sick Sinus Syndrome are conditions that cause abnormalities of the electrical charge that stimulates the chambers of the heart to contract and pump blood through a dog’s body. These conditions may cause a very slow heart rate and as a result dogs become lethargic and experience episodes of collapse or fainting. If left untreated, their heart could eventually stop beating, resulting in sudden death.

Even though these are serious illnesses, treatment is available that can help give a dog suffering from these conditions the ability to lead a normal life—a pacemaker implantation.

According to Dr. Kleman, studies show that if dogs who have complete heart block don’t get a pacemaker, they may pass away within six months.

“This devastating consequence is secondary to an unstable electrical rhythm within their heart. They can basically pass away at any moment,” said Dr. Kleman.

No one can say for sure why dogs develop Complete Heart Block, since it is something they are not born with nor is known to be genetic.

“It’s something they acquire over the course of their life, a type of scarring within their heart,” Dr. Kleman said.

Both Complete Heart Block and Sick Sinus Syndrome are something that family veterinarians may find during an annual exam. Which is another reason why yearly or bi-yearly exams are so important for dogs to have, especially older ones. “Often we find complete heart block during an annual exam when your veterinarian finds a low heart rate of 30 beats per minute. This heart rate is abnormal and an electrocardiogram (ECG) is then used to diagnose Complete Heart Block,” Dr. Kleman said.

The procedure takes approximately 60 to 90 minutes and is a minimally-invasive procedure. During the surgery, dogs receive two small incisions, about an inch to an inch and a half in length, one on the bottom of their neck near their chin and the other on the back of their neck.  The pacemaker lead is then placed into the dog’s heart through their jugular vein and the pacemaker computer is placed under the skin in the back of their neck.  Unless complications arise, patients are sent home the next day. Once they are home, they are required to be strictly rested for six to eight weeks to ensure that the pacemaker lead stays in place.

“The dogs wake up from surgery having very little discomfort and having a brand new heart rate,” Dr. Kleman said. “Typically the biggest problem we have with pacemaker surgery is the recovery time, because the dogs feel like absolutely new dogs.”

Scottie, an 8-year old Pembroke Welsh Corgi, received a pacemaker last year after being diagnosed with Complete Heart Block.  A few months before his diagnosis, his owner, Mari Carroll, began to notice that this championed herding dog was now lacking the energy he once had.

“Eventually, he got to the point where one morning he didn’t eat, which for a Corgi is really unusual, they live to eat. And then later that morning I was watching him outside and I saw him faint.” Carroll said.

She took Scottie to her local veterinarian who after completing an ECG, discovered his heart rate was only beating at a mere 35 beats per minute. That was when she was referred over to Dr. Kleman at CUVS.

Dr. Kleman is one of about 230 veterinary cardiologists who are trained to perform pacemaker surgery in dogs. “One of my favorite things about pacemakers is first the immediate gratification; that we can make a patient better overnight (within 12 hours)” said Dr. Kleman.

“The hardest thing for [Scottie] was once he had the procedure and the pacemaker was put in, I picked him up the next day and he had to be confined to a crate for six to eight weeks,” Carroll recalls, “so he was hand walked and was basically on crate rest for all that time and it was unfortunate for him because he felt great and he couldn’t understand why he had to be so confined.”

This technology, thought to be reserved only for humans, has been available to treat dogs with these conditions since the late 1960s. Pacemakers, which are about the size of a silver dollar, help to speed up a slow heart rate and can help to extend a dog’s life by years. These patients will typically live their normal lives after their recovery period.

Since there are no pacemakers made specifically for veterinary use, the pacemakers implanted in dogs are the same as those used in humans. In order to keep costs as low as possible, veterinary cardiologists rely on hospitals to donate unused pacemakers whose battery lives are shortened and are no longer appropriate for use in humans.

“The pacemakers I put in dogs typically have a battery life of about 10 years and this timeline is just not long enough for a person anymore,” said Dr. Kleman, “So these are brand-new state-of-the-art pacemakers that just have a little bit shorter shelf life.”

Over the years, pacemaker companies such as Medtronic and St. Jude Medical have made hefty donations to cardiologists. CanPacers, or Companion Animal Pacemaker Repository is another way cardiologists can obtain pacemakers. They are a non-for-profit organization that sells donated pacemakers to veterinarians for about $500 for both the pacemaker generator and lead. According to their website, all proceeds from their sales are used to fund Cardiology Resident Research Projects at the American College of Veterinary Internal Medicine.

Implanting pacemakers in dogs is more common than most dog owners might think. Dr. Kleman typically implants about eight to 12 pacemakers in dogs a year but says that hundreds of pacemakers are implanted in dogs yearly across the country.

While some may think that pacemaker implantation is expensive, the surgery is no more than the cost of knee or back surgery for a dog. It can range from approximately $2,500 to $5,000 depending on where you are located in the country.

“Financially, it’s tough, its a lot of money” said Carroll, “[Scottie] was dying, so there wasn’t any question. Of course there are huge costs, it’s just part of having dogs.”

Carroll recalls that she didn’t realize how much Scottie had been affected by his disease until after the pacemaker was put in.

“Before I would take him on walks and he would kind of loaf along behind me, and that is not his style, he likes to be out in front leading the way,” she said.

Since having the pacemaker implanted, Scottie has no limitations and is free to lead a normal life. The biggest difference Carroll sees in Scottie since his surgery is his energy level.

“He’s much happier, his whole attitude is better,” she said. “He’s up for anything, he loves to go out on walks and race around the yard with the younger dogs. He’s back to his old self. ”

By Gabriella Martinez | Photos Provided by CUVS