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Texas: 50 Years Since First Artificial Heart Implant Surgery

Nine-year-old Billy Cohn was never the most serious-minded of young students, but the biggest news story of April 5, 1969, definitely commanded his attention.

The Houston Chronicle reports next to his cereal bowl, Billy's mom had placed the morning paper's account of Dr. Denton Cooley's implantation of an artificial heart, an event that wowed the boy as much as adults. He brought the article to school, Memorial Drive Elementary, sharing it with classmates rather than listening to the teacher, who came to his desk to confiscate the distraction.

When she saw the article's subject, she instead told Billy to tell the entire class about the breakthrough.

"It was pretty cool," recalls Cohn, now a heart surgeon and inventor. "There I was standing up in front of my peers telling them about the artificial heart. You can imagine what an inspiration the device became for me."

Fifty years later, the story of the first artificial heart's implantation endures: science fiction made reality, cautionary tale, the event that launched one of medicine's most famous feuds, a dream still being pursued. It is one of Houston's signature stories but also a subject of continuing interest around the world.

Its legacy can be seen in the mechanical cardiac parts people now take for granted -- valves, pacemakers and, most of all, support devices that currently help diseased hearts better pump blood. Nothing stimulated interest in the new field like Cooley's audacious effort to save a dying patient with the help of a device previously deemed not ready for use in people.

Its enigma can be seen in the fact the device Cooley implanted was never used again.

The need hasn't gone away. Despite cardiac advances such as statins and stents, some 500,000 patients in the United States die of heart failure annually, more than 1,000 a day. Medicine has mastered the transplantation of donor hearts, but most years there are only 2,000 to 3,000 available.

Cohn says it's amazing there's not yet an artificial heart that can be taken off the shelf and sewn into a gravely ill patient, given that prostheses exist for most every other structural part of the body that fails. But he says artificial heart efforts are getting "close."

"It's interesting how we're still mesmerized by the idea of replacing the heart," says Shelley McKellar, author of "Artificial Hearts: The Allure and Ambivalence of a Controversial Medical Technology" and a medical historian at the University of Western Ontario. "In 1969, after the artificial heart was implanted, it was seen as something that probably wasn't going to happen."

The story dates to the early 1960s, when famed Houston heart surgeon Michael DeBakey led a contingent of scientists to Capitol Hill, telling Congress that an artificial heart could be brought to "full fruition if we had more funds." The researchers were rewarded with $10 million.

Houston became the effort's epicenter, partly because of DeBakey's stature and partly because of the city's NASA era "anything-is-possible" spirit. DeBakey's research team spent the ensuing years developing hearts and testing them in animals at Baylor College of Medicine and, by 1968, they had put a prototype in a number of calves. But none lived longer than 40 hours and DeBakey thought the project needed more work before trying it in patients.

The verdict didn't sit well with Dr. Domingo Liotta, the device's inventor. Frustrated, Liotta brought the device to Cooley, DeBakey's one-time protege who'd seven years before founded the competing Texas Heart Institute. In the coming months, the two tweaked the device.

On April 4, 1969, Cooley implanted the device in ailing heart patient Haskell Karp at St. Luke's Hospital, surgery that made front-page headlines around the world the next day. Karp survived the operation but died within the week, less than two days after getting a donor heart.

The operation touched off the most sensational medical controversy in Houston history. DeBakey complained the heart had been covertly taken from his lab and Cooley was censured by the American College of Surgeons. The two giants wouldn't speak for decades -- a falling-out immortalized in a Life magazine cover story entitled "The Feud" -- before reconciling a year ahead of DeBakey's 2008 death.

The device actually did its job, buying Karp time until a donor heart could be found. But it didn't set off a wave of implants across the nation. Some historians dismiss it as a "one-off."

The consensus was the technology was premature, based on its performance in animals. It didn't help that patients transplanted with donor hearts at the time didn't survive long, a result of rejection issues researchers had not yet figured out. Those outcomes nixed the device's possible role as a bridge to transplant.

Doctors appreciated Cooley's effort, but many thought if the world's most skilled surgeon couldn't make it work, there probably wasn't a future for it, says McKellar. Could a man-made device really take the heart's place, pump blood without clotting or eventually breaking down, without ever taking a break?

"DeBakey had made a statement early in the 1960s that he expected there to be 200,000 artificial hearts in people by the end of the decade," recalls Dr. Michael Reardon, a heart surgeon at Houston Methodist Hospital. "It showed how wildly overoptimistic we were in trying the understand the complexities in building an artificial heart."

Following the implantation, Cooley attended scientific meetings where he spoke about what he learned from the operation -- how Karp's blood reacted in the device, how the device performed in Karp compared with animals. McKellar says Cooley was seen as contributing to the discussion, but it was unclear it the procedure affected the direction of the future direction of mechanical heart parts.

McKellar says the Karp surgery became viewed as a cautionary tale, exploding issues of when a patient can truly give consent and when's the appropriate time to move experimental procedures from the laboratory to the bedside. But she acknowledges Karp was within days, even hours, of dying without surgery, a prognosis that "emboldened a sort of what's-there-to-lose attitude" in doctors and patients brave enough to be the first to try a new procedure.

McKellars says the implantation's key contribution was to shine a spotlight on artificial heart research and raised public expectations that such technology would one day work, that better mechanical devices would be forthcoming. It ignited a new enthusiasm for imagining mechanical devices and spare parts, she says.

In recent decades, the emphasis has shifted to alternatives, known as left ventricular assist devices (LVADs), that do not replace the heart but assist the chamber that pumps blood throughout the body. The approach was pioneered by DeBakey after he abandoned research into the total artificial heart.

In the early incarnations, LVADs saved lives as bridges to transplant, but they were considered too big and not durable enough. In time, improvements led to their implantation in more than 60,000 patients now, some of whom have lived years with the device. Former Vice President Dick Cheney lived 20 months with one of the devices, all the while improving enough to go on the heart transplant list, then get a donor organ.

"The artificial heart's legacy is the stimulation of physician scientists and device companies to develop powerful support devices for the heart that are now smaller, more capable of increasing cardiac output from the heart, less likely to develop blood clots and reliable for years," says Dr. James Willerson, president emeritus of the Texas Heart Institute. "Today, they often return a patient to an active lifestyle relatively free of heart failure symptoms."

Original pumps were large "pulsatile" devices, which mimicked the beating of a heart as they pumped blood. Today, they're smaller "continuous-flow" device, which continuously spin blood through the arteries.

Reardon says the next advance will be miniaturized, catheter-delivered assist devices. He thinks the devices will take over enough cardiac function, indefinitely, and give the patient's time to rest and recover, without requiring time in the hospital.

It is a scenario McKellar thinks will still be the most frequent use of mechanical heart devices 50 years from now.

But the idea of a total artificial heart that replaces the diseased organ is very much alive, despite concerns from the 1980s to early 2000s that the unwieldy devices didn't enhance life so much as prolong patients' painful journey to death. The leading device now -- the Food and Drug Administration-approved SynCardia -- has excited the field because it's small and portable and has saved lives as a bridge to transplant. Still, it has its limits -- its power source is battery pack stored in a lunchbox-sized pouch outside the body.

The top hope now is a miniaturized device being studied at the Texas Heart Institute -- the BiVACOR -- that uses magnetic levitation technology to circulate blood around the body. It was developed by a mechanical engineer from Australia's Gold Coast, who eventually persuaded Cooley and Cohn that its continuous flow of blood could work where other devices had failed. It has worked beautifully in calves, says Cohn.

Cohn, who says the hope is to implant the device in patients in 2021, envisions a future in which the device keeps people from dying of heart disease. He says he knows that sounds crazy, but points out that the Wright brothers could never have imagined 600 people at 35,000 feet flying from New York to Los Angeles watching a movie and eating dinner.

"It's hard to see that far over the horizon when you're in the early stages," says Cohn.

Copyright AP - Associated Press
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