The Ticker

A new book reminds us that the heart is still a medical mystery—and a marvel.

Illustration by Andi Watson

Besides libidinous hardware, no human organ has held our interest through millennia of civilization more than the heart. As recently as the late 1800s the heart was still thought of by many as the seat of our souls; the root of thought, emotion and love, and, in turn, Valentine’s Day schwag. The Aztecs assumed the organ was the individual—and also a fragment of the sun’s pulsating heat—and during wars and sacrifices tore them out still-beating with Temple of Doom abandon. The ancient Egyptians weighed hearts of the deceased against a single feather; the light-hearted passed into the afterlife while a heavy heart meant being devoured by a monster with the jaws of a crocodile, the body of the lion, and the rump of a hippopotamus.

Until relatively recently healers wouldn’t touch the sacred ticker. In 1893, prominent Austrian surgeon Theodor Billroth commented, “The surgeon who should attempt to suture a wound of the heart would lose the respect of his colleagues.” With modern medicine this reluctance faded. Alongside the space race mending broken hearts became one of the major scientific pursuits of the mid-20th century. In 1967, South African surgeon Christiaan Barnard graced the cover of Time magazine after performing the first successful human heart transplant. Various other high-profile feats of cardiac surgical success followed. But eventually the hype fizzled. Too many patients didn’t make it. Plus, another organ was after our attention.

Since the ’80s, our collective awe has migrated from heart to brain, the actual seat of our thoughts, our emotions (our souls?). Pop neurology and psychology are now everywhere; pop cardiology is not. Obama’s multibillion-dollar BRAIN Initiative finds its way into near daily news stories and think pieces. Despite cardiovascular disease being the leading cause of mortality, research into it is not the glitzy headline it once was: “It’s all simple plumbing and a pump,” a neurologist recently commented to me.

Biologist and writer Rob Dunn thinks otherwise. In his new book The Man Who Touched His Own Heart, Dunn reminds us that the heart remains a fascinating, far-from-understood organ with an incredible biologic and cultural history. Even as scientists methodically map the human brain’s 100 billion neurons, the heart—and heart research—keeps on beating (sorry).

The book opens in a dingy, makeshift Chicago hospital where, in 1893—the same year Billroth cautioned hands off the heart—a young black surgeon named Daniel Hale Williams performed the first successful cardiac surgery. His patient had been stabbed in the heart during a bar fight. Williams, seeing no other options, cut into the man’s chest wall, pushed a rib aside, and for the first time sewed up a live human pericardium, the fibrous sac surrounding the heart.

Despite some awkward leaps in chronology, Dunn then manages to weave thousands of years of convoluted historical and scientific anecdotes into a clear, engaging account of the heart’s long and gruesome history—a jarring reminder of the guts and gore behind so much scientific discovery. By the 4th century B.C., the Egyptians were no longer weighing hearts—they were performing the first known scientific dissections at Alexandria’s medical school. Their subjects: live criminals.  Galen made a living patching up gladiators (while peeking at their organs in the process). He also seeded our current understanding of the cardiovascular system by dismantling every animal he could get his hands on—the elephants must have been a chore—and, in doing so, kicked off 2,000 years of animal testing.

The Renaissance thinkers were key to understanding the inner workings of the heart. They probed prisoners, robbed graves, and were occasionally burned at the stake for questioning God’s domain. Dunn spends a good deal of time on Leonardo da Vinci, an avid dissector. The polymathic Italian observed rivers to understand blood flow and, it’s speculated, may have produced the ultimate treatise on anatomy. Sadly, it was lost to history after Leonardo’s 1519 death.

Rob Dunn
Author Rob Dunn.

Photo by Casey Tarpy

Dunn moves on to more recent, more astounding advances, like German surgeon Werner Forssmann feeding a catheter up his own arm vein and into his heart in 1929. After literally kicking off a colleague trying to yank out the tube, Forssmann quickly snapped two X-rays confirming success—afterward, according to Dunn, he “had good food and a lot of good wine and celebrated the birth of a new field of medicine, what would come to be called cardiology.” (The moment also gives Dunn’s book its title.) The madness continues with a delve into transplant science and its long, strange history of chimeric experimentation, including an Ethiopian leg transplant in 400, a Chicago surgeon transplanting bits of cadaver testes into his own in the interest of enhanced virility, and the race to transplant a human heart. The latter tale thrills, though the back stories on other cardiac modernities—bypass surgeries, angiograms, and electrocardiograms included—can drag. During the saga of the pacemaker battery, I hoped something would jolt the book back to life.

The narrative shines where Dunn seems most at home: the lab. He has a knack for translating complex, cutting-edge science into clear and approachable language, as when he traces the evolution of our own heart and blood vessels back to the simple sponge: “It is filled with pipes through which the sea can be moved … the sea itself is part of the sponge’s heart,” he writes. Dunn explains how diet shapes our heart health—how compounds called sialic acids from animal meat find their way into our heart cells, causing autoimmune activity that might contribute to heart disease. He also profiles researchers mathematically modeling the heart down to the individual cell, and others growing hearts from scratch using plastic mesh and stem cells.

If there’s one recurring omission in The Man Who Touched His Own Heart, it’s a deeper discussion of the often brutal cost of scientific knowledge. Dunn does examine the controversies shadowing human heart research through the years, acknowledging the often queasy Frankensteinian bravado behind scientific progress. Particularly heated was the 1970s debate on what constitutes “death”: a dead heart or a dead brain. (Surgeons were itching for live hearts to transplant and often went to ethically dubious lengths to get them.) However, a closer look at the lives of the animals poked, prodded, and sacrificed in the name of science is warranted. Even today, find yourself in a surgical “beagle lab” and PETA might have a new recruit.

Dunn’s straightforward style, clunky metaphors and all, could benefit from a consult with the science writer literati: a hint of Mary Roach’s wit, Atul Gawande’s eloquence, Oliver Sacks’ cerebral neurologic weirdness. Still, Dunn is an impressive storyteller, especially considering writing isn’t really his day job—that would be studying the “refuse consumption of urban arthropods.”

Though we’re now wowed by the brain, The Man Who Touched His Own Heart reminds us that the heart is far more than a pump and a mess of tubes, and to respect our most vital muscle. Especially since our greedy, oxygen-hungry cerebra owe everything to the heart’s complex, coordinated contraction. The heart can beat on without the brain so long as it has oxygen. If your heart stops, your brain goes blank in three minutes.

The Man Who Touched His Own Heart by Rob Dunn. Little, Brown.

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