12/08/00- Updated 05:41 PM ET
The heart of a tiger
Karma needs surgery to repair his ailing heart.
Photo © Jeff Stead, Tyler (Texas) Morning Telegraph
Dec. 7, 2000
By Steve Sternberg, USA TODAY
Karma's future seemed assured. Saved three months ago from a neglectful "backyard" breeder, the 5-month-old Bengal tiger cub was scheduled for an unprecedented operation Saturday to repair his malformed heart. But the furry, 41-pound baby's labored breathing became much worse this week. Now Karma is so weak that his doctors may postpone surgery, says Karma's savior, Brian Werner, who founded the Tiger Creek Wildlife Refuge near Tyler, Texas, part of his Tiger Missing Link Foundation. "It may be delayed for a few days, depending on his condition, which we're evaluating," says Terry Fossum, chief of veterinary surgery at Texas A&M.
Werner says the breeder is one of many who benefit from lax regulations to breed jungle cats for profit. He apparently mated Karma's mother, Katrina, with a family member. "We think they were too closely related," says Werner, who suspects inbreeding caused the cub's heart defect. In humans, the defect results from a developmental error.
Karma suffers from a quartet of malformations, known collectively as the tetralogy of Fallot, for the French doctor who first described the defect in the 1880s. Tetralogy is the sixth-most-common congenital heart defect in dogs, and it is seen in calves, colts and cats. No one knows how often it occurs in jungle cats.
Karma's doctors are an unusual collection of veterinarians and pediatric heart specialists skilled at repairing tetralogy of Fallot in children. They will have to reshape Karma's heart. Hearts with tetralogy of Fallot have a blocked pulmonary artery, the vessel that ordinarily carries oxygen-depleted blood to the lungs.
There's also a hole between the heart's right and left pumping chambers. The hole allows oxygen-rich and oxygen-poor blood, ordinarily kept separate, to mingle in circulation.
"Blue blood gets out to the rest of the body," says Charles Fraser, chief of heart surgery at Texas Children's Hospital, who will do Karma's repair. "His tongue is blue, and he pants a lot because he isn't getting enough oxygen."
Without the repair, Karma's body will outgrow his heart's ability to nourish it with blood. "The animal is suffering, and it will get worse," Fraser says. "This is fatal if untreated."
If the surgery goes forward, it might represent the first time that doctors have tried to fix tetralogy of Fallot in an infant jungle cat.
"I don't believe anyone's attempted this in a tiger before," says Sonya Gordon, a veterinary cardiologist at Texas A&M.
Gordon and her colleagues at the vet school see exotic animals regularly — lions and tigers among them — when private owners bring them in for routine medical care. But few, if any, veterinary centers in the USA perform open-heart surgery on animals, because specialized technology isn't available, except in research settings. "We're, on average, 20 years behind human medicine," Gordon says.
Fossum, the Texas A&M surgeon, says that may change, beginning with Karma's surgery. For the past year or so, she says, the university has worked to expand a collaboration with the Texas Heart Institute.
The institute, home to famous heart surgeon Michael DeBakey, recruited the Texas A&M team to assist in the first animal tests of the DeBakey-MicroMed Left Ventricular Assist Device, an implantable heart pump designed for humans with heart failure.
Now doctors at both centers are preparing to establish a coronary center for veterinary patients, mostly cats and dogs. "I hate to use the term flippantly," Jensen says, "(but) Karma would be a great poster child. He's four times the size of a common house cat, which makes him a good candidate for training."
Unlike common house cats, Gordon notes, "his feet are just huge."
During the four- or five-hour operation, Fraser, Fossum and other doctors will use Dacron or Karma's own tissue to patch the hole in his heart. They will refashion Karma's pulmonary artery, restoring blood flow to the tiger's lungs, and fix other defects typical of this condition.
Fraser says he has repaired the same set of defects in perhaps 200 children. But he has never been in the operating room with a Bengal tiger.
"I'm excited," he says. "I've seen tigers in zoos, but I've never touched a tiger. I've read a lot about tigers in the wild, and their plight, and this seems to me like a good thing to do."
In the wild, tigers are dying off, the result of poaching, habitat destruction and isolation, Werner says. Only about 3,500 to 4,000 survive in the wild worldwide, just one-third of the number now living in captivity in the USA.
Werner's refuge is supported by donations and operates on a shoestring budget, rescuing tigers that have been abused, neglected or displaced.
Founded three years ago with three tigers, Tiger Creek now has 18 tigers, four lions and two pumas to house and feed. They consume 240 pounds of meat a day.
Werner says he has begun genetically testing tigers for a registry that he hopes will provide the first index of genetic diversity in captive tigers.
Werner learned of Karma's ordeal soon after his birth. A source alerted Werner that Katrina, Karma and his sister Kali weren't being properly cared for. Werner called the owner, who agreed to send the family to Tiger Creek. They arrived on Sept. 5. In October, a staff veterinarian diagnosed Karma with a heart murmur and referred the cub to Texas A&M for a definitive diagnosis.
Fraser says his four children are thrilled that he's trying to help Karma get better, especially his 7-year-old daughter, Gracie. "She's the sort of child that would adopt any stray anything," he says. "We have dogs, birds, gerbils and fish." The children want to meet Karma; the family hopes to visit him.
If all goes well, Fraser and his children will have many opportunities to visit the cub. But there are no guarantees. No one knows how well Karma will function on the heart-lung machine, because no tiger has been hooked up to one.
Karma's postoperative care also promises to be a challenge, Fossum says, because wild animals hate to be restrained. "It will be difficult to keep him quiet, and it will be difficult to keep him from chewing on his catheters."
Copyright © 2002 Tiger Missing Link Foundation. All rights reserved. TEXT MENU