Artificial Hearts

An optimist may see a light where there is none, but why must the pessimist always run to blow it out? Michel De Saint-Pierre, quoted in Wisdom for the Soul

Artificial Hearts

image by: Texas Monthly
     

 

The human body is not a machine, but it is analogous to one. Its parts wear out and, if they are not replaced, the whole organism can cease to function, at least at the same level as in youth. Thus the quest for methods and means to restore the body to an earlier, healthier state has become big business.

Joint replacements, for example, are now common: In the United States each year, more than 600,000 knees are replaced with artificial ones, and the annual demand for this surgical procedure is expected to surpass three million by 2030, according to the American Academy of Orthopaedic Surgeons. The heart is, of course, a much more complex component of the human system than a joint. Indeed, it might be said to be the body’s core component. And, unlike so many parts of the human anatomy that are bilaterally redundant—knees, hips, eyes, ears, lungs, kidneys—the heart stands alone. It has no backup in performing its nonstop task of beating 70 or so times a minute, or about 115,000 times a day, which amounts to more than 2.5 billion times in an average lifetime. No wonder hearts get tired and wear out, with deficient ones needing to be repaired, or even replaced, if life is to go on.

The first human heart transplant was performed in 1967 by Christiaan Barnard, operating in South Africa. Half a century later, the number of organ transplants still pales in comparison to artificial joint-replacement procedures. And the number of heart transplants is comparably tiny: According to the United Network for Organ Sharing, in the past three decades there have been a total of some 70,000 performed. Currently, almost 4,000 people are on a waiting list for a heart transplant: The only candidates who will receive one are those lucky enough to be matched with a compatible donor before their own heart gives up the ghost.

This scarcity is why doctors and researchers have long recognized the need for an artificial organ, or at least a machine of some kind that can assist a diseased heart until a transplant candidate can be found. The holy grail is a device that would make transplants altogether unnecessary.

The search for that grail has been, as Mimi Swartz shows in her fascinating book, as complicated as the essential organ itself. “Ticker: The Quest to Create an Artificial Heart” tells a story as big as Texas—which should not be surprising, given that Houston has, since at least the 1960s, been considered the “place to go” for heart surgery. Ms. Swartz is the executive editor of Texas Monthly magazine and a co-author of “Power Failure,” about the collapse of the Houston-based energy company Enron. “Ticker” introduces readers to a dizzying array of hospitals, medical centers, institutes, laboratories and garage workshops where investors, inventors and innovators have been hard at work. In part because of the local focus of Ms. Swartz’s reporting and writing, the most well-developed characters are native or adopted Texans.

Among Ms. Swartz’s main characters is Michael DeBakey, a Tulane-educated Louisianan who in 1948 ended up in Houston, where he eventually came to lead the Baylor College of Medicine at the Texas Medical Center. DeBakey, a persuasive physician who knew how to extract gushers of donations from rich oilmen, also became a staunch advocate of federally funding medical research—not only to develop an artificial heart but also to create and promote related machines that help keep the heart beating, such as the left ventricular assist device. After his team inserted an LVAD into a 37-year-old woman in 1966, Ms. Swartz writes, his Houston waiting room quickly began to be “packed with the rich and famous—from out of town.”

Among DeBakey’s students was Denton Cooley, born and educated in Texas and reputed to be the fastest open-heart surgeon in the West—or anywhere in the world. Cooley established himself at the competing Texas Heart Institute in Houston, becoming his former mentor’s archrival. And he had a very ambitious goal: Nothing short of a totally self-contained artificial heart. The DeBakey-Cooley divergence provided a paradigm for the whole field of heart surgery: A key question became whether an artificial heart was in fact an overly ambitious goal. At many times over the years, it has seemed so.

Ms. Swartz opens and closes her book with another native Texan: Bud Frazier. Also a student of DeBakey, Dr. Frazier proves to be perhaps the most unforgettable character in the narrative, not only for the way he doggedly has pursued an artificial heart but also for having an outsize heart of his own, as the author shows by introducing us to some of his patients. In 1981, Cooley hired Dr. Frazier to take over running artificial-heart research at the Texas Heart Institute, but Ms. Swartz follows his successes and failures from the 1970s through to the present day.

Dr. Frazier played a key role in turning the use of LVADs from an experimental procedure into a relatively common one. For years, he was the doctor that both patients and device makers turned to most frequently when seeking new or experimental approaches. Ms. Swartz also tells the story of a young female patient, “one of Bud’s favorites,” who is currently walking around with an LVAD called the HeartMate II in her chest—and is hoping that a new artificial heart, called Bivacor, will be ready for implantation in humans by the time she needs it.

But no doctor, no matter how distinguished or dedicated, could by himself do all the research, experimentation and development necessary to create a truly mechanical heart. This is where the tinkerers, engineers and entrepreneurs come in. Starting as early as the 1960s, when heart-surgeon pioneers suddenly grew in renown, an endless parade of hopeful partners beat a path to operating-room doors with their own ideas, models, prototypes and dreams for artificial hearts.

The wild early days of heart research had coincided with the period when NASA was trying to put a man on the moon, and Houston became the linchpin of both engineering efforts. The importance of engineers working alongside doctors and physical scientists turns out to be a leitmotif of Ms. Swartz’s book. While physicians like DeBakey and Cooley became household names in their time, the engineers (working in windowless basement laboratories amid the barnyard noises and smells of the sheep and calves into which they sewed their prototype hearts) did not.

With the patience of systematic experimenters, the engineers improved their machines deliberately and incrementally over the years. According to Ms. Swartz, doctors anxious to move ahead with procedures on human subjects rather than on livestock accused the engineers of being perfectionists and became impatient. But that feeling of urgency worked against the greater good, since those brave pioneers given early artificial hearts did not fare well—most notably Barney Clark, into whom the Jarvik-7 artificial heart, developed at the University of Utah, was implanted in 1982.

Clark lived for 112 days, but he suffered so many complications that his case seemed to cast doubt on the whole artificial-heart enterprise. “Barney Clark’s story became one of dashed hope,” Ms. Swartz writes, “as it became painfully clear that American know-how couldn’t do for the human body what it had done for space exploration.”

Indeed, funding for artificial-heart and transplant research and experimentation had already begun to slow back in the 1970s, coinciding with a rise in regulation of all kinds. The Wild West of Houston and its custom-cowboy-boot-clad surgeons was reined in. But the doctors and engineers who had made the quest for an artificial heart their lives’ work were not deterred. They just faced a greater challenge to get it right.

It was around this time that Bud Frazier made what was perhaps his most significant (and at the time controversial) contribution to the history of the artificial heart. He changed his mind on the basic question—an almost philosophical one—of whether an artificial heart should produce a steady flow of blood or a periodic sequence. The latter is what a natural heart does, of course, gently pushing the blood along, and that periodicity is what results in a person’s familiar pulse.

Among the technical obstacles to developing a reliable artificial heart, however, is the very blood that it moves. Blood can produce life-threatening clots if it is not kept flowing at the right rate, and its cells can be damaged by mechanical impellers or other unforgiving components of the machine. An embedded steady-flow heart might seem unsettling to some patients, since they would lack a heartbeat. Yet from a mechanical point of view, continuous flow is simpler to produce, and many artificial-heart inventors have thus pursued that option.

The debate continues, as does the quest to create hearts that could not only save lives but even be fully tailored to each patient—“a perfect fit,” as Ms. Swartz puts it. Just like custom-made cowboy boots.

Source: Henry Petroski, ‘Ticker’ Review: The Race to Reinvent the Heart, The Wall Street Journal, August 3, 2018.

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Last Updated : Wednesday, November 25, 2020