No Pulse: How Doctors Reinvented The Human Heart

This 10,000-rpm, no-pulse artificial heart doesn't resemble an organic heart--and might be all the better for it

By Dan Baum Posted 02.29.2012 at 12:13 pm 37 Comments

Flow State: Jack Thompson

When Cohn and I entered the operating room, all we could see of Meeko was a tall mound of blue surgical drapes and a red rectangular cavern: Meeko’s chest cavity. Other surgeons had prepped the calf for surgery. Cohn was stepping in, as usual, to work the final miracle.

Twenty-eight people attended—technicians running the heart-lung machine, anesthesiologists, veterinarians of various stripe, photographers and goggle-eyed medical students. Everybody was walking around and talking; it was like a big cocktail party, only the guests wore scrubs and all you could see above their masks were their eyes. Among the guests was Bryan Lynch of MicroMed, the hedge-fund-wrecked company, now risen from the dead. Lynch and a few others from the company’s early days had bought their company back from the debris of Absolute Capital Management for a net outlay of $2 million—pennies on the dollar—and had a design that put the magnets in the blades of the screw instead of the axle. That shrunk the axle and made the blades bigger, which meant the screw could turn more evenly. That and a new silica-carbide bearing, Lynch hoped, would reduce the risk of creating dangerous blood clots. It was MicroMed’s pumps that Cohn was preparing to implant in Meeko’s chest.

Overhead, a big flat-screen TV, connected to a miniature camera on Cohn’s forehead, gave us a surgeon’s view of the procedure. The medical students gazed at it raptly. I didn’t use it because Cohn had told me to stand at his left elbow, where I could peer straight down onto the calf’s red, thrashing heart.

Working with an electric cauterizing scalpel that sizzled as it touched flesh (and sent up a distinct steakhouse aroma), Cohn peeled tissue from around the heart. The more its constraints were peeled away, the more vigorously the heart seemed to buck. “Go on!” Cohn yelled, which was the signal for the heart-lung machine to take over. A thick transparent tube filled with dark, purple blood from the calf, and another tube returned it a livid red. With a few deep, swift strokes, Cohn cut the heart free and lifted it on his palm. He left the atria of the heart—a sort of lid, where the big vein and artery go in and out—inside Meeko’s chest. The rest of it continued to beat as he laid it in a basin because residues of blood remained in the small coronary arteries. Cohn cocked an eye at me over his mask. “I’ll bet you’re thinking, ‘How dare he.’ ” Actually, what I was thinking was: Thus begins my life as a vegetarian.

Working fast, Cohn sewed collars of rubberized Dacron onto the atria. His stitching looked like plain old needle-and-thread work, low-tech and almost casual in its rapidity. Within a few minutes, he had fixed in place two white, doughnut-shaped collars. He lifted the turbines from a dish of saline, their rubberized-Dacron dolly dresses dangled from them. They were marked “Not Approved for Human Use,” but each was smaller than the HeartMate II, another advantage MicroMed hopes one day to exploit.

Working as deftly as ever, Cohn sewed the dolly dresses onto the collars he’d installed in the atria. There was no dramatic moment when the turbines were activated and the heart-lung machine turned off; it happened sometime during the third hour of surgery. But at one point, I noticed that the blood-pressure monitor no longer displayed two numbers—120 over 80—but one: 78. “Usually we measure blood pressure at the moment the heart squeezes and the moment it relaxes, the systolic and diastolic numbers. This calf has only one now. And check out the pulse.”

Flatline. William Shakespeare, many scholars believe, wrote sonnets in iambic pentameter to imitate the sound of a human heartbeat. What, I wondered, would the Bard make of this?

Cohn kept freaking me out doing magic tricks. In the elevator on our way upstairs from the operating room, he pulled five one-dollar bills from his pocket. “Five singles, right?” he said. He turned the bills over in his hand and swiveled the palm upward with a flourish. The five ones had turned into five 100s. There was nothing up his sleeve; he still had on his short-sleeved scrubs.

Back in his office, he asked me to pick a card at random from a deck, look at it, and put it back in the deck. It was the 10 of diamonds. He told me to draw a shape in the air with my finger. I drew a triangle. “Think of a color but don’t tell me what it is,” he said. I thought of green. He cut the deck, and there was the 10 of diamonds, a green triangle inked on it. I almost passed out.

It wasn’t until that evening, when we sat in a windowless break room drinking terrible coffee, that he revealed why he’d kept showing me magic tricks—to refute, in a way, Arthur C. Clarke’s famous dictum, that advanced technology is “indistinguishable from magic.” First, though, Cohn set aside his coffee and cracked his knuckles. “Now,” he said in a P.T. Barnum voice, “I’ll show you the amazing disappearing saltshaker. Usually I do this with a special silk, but . . .” He looked around, grabbed a stiff brown paper towel, shrugged, and wrapped the plastic shaker in it. “No, wait,” he said, the smoothness of his act ruined. “This is the amazing saltshaker-through-the-table.” He set the wrapped saltshaker down on the table with a loud clunk, stopped, took it away, and said, “Sorry. Maybe it’ll work better with these.” He put some packets of pepper on the table, thought a second, and then swept them away. Something had him rattled, I couldn’t tell what. “No, it’s the saltshaker. That’s right.” He set it up on the table again with one hand and smacked it hard with his palm. The paper towel flattened out, and we heard the saltshaker bounce off the floor below the table. I bent to retrieve it, flummoxed.

“OK,” he said gently. “Let me deconstruct it for you.” All those fumbling mistakes with the silk and the pepper packets were, as it turned out, part of the trick, designed to distract me from what was really going on: his molding the stiff paper towel to the saltshaker and secreting the shaker under the table. When he smacked down the towel, he released the shaker, which he’d been holding under the table. “It’s all part of a script. Every word I said, every motion of my hands, had a role in making the trick work. It seemed random—even like mistakes—to you. But it was all part of the script.”

He sat back and spread his hands. “That’s what heart surgery is,” he said with a soft laugh. “It’s a script. To you, it probably looked like I was just sewing those collars into Meeko’s chest any old way. But every motion was planned, tested, practiced. Turn my hand eight degrees and poke the needle through; swivel my hand back 22 degrees and draw the needle up four inches; turn my hand back just so and bring it to the left a half inch: a precise number of stitches, pulled just so tight and no tighter. What heart surgery takes is remembering an incredibly long and complicated script and following it exactly, step by step.”

Walking back to his office, I pressed him on how long it would be before people were walking around with continuous-flow artificial hearts. Some people think that pressure from the medical-equipment industry makes the FDA too hasty in approving new medical devices. Others think the opposite—that pressure from the insurance industry makes the FDA drag its feet, because insurance companies don’t want to pay for expensive new therapies or, god forbid, keep deathly ill people alive longer. Cohn was in neither camp. “They have a hard job to do, and we want them to be careful,” he said as we sat down again amidst his playing cards and heart models. Besides, the technology really isn’t ready, he said. Using two turbines, with two computerized controllers, is cumbersome. “It really needs to be one integrated unit.” That will take another three or four years to develop, he estimated, and then another six or seven for the trials necessary for FDA approval. But the principle has been proven, he thinks. The delay didn’t bother him; it’s part of scientific advancement: “The Wright brothers flew 800 feet in 1903, and commercial air travel began in 1920.”

“Oh, hey! Look at this,” he suddenly cried, pawing through the mess on his desk. He came up with a small cardboard box. On the lid, he’d pasted a photograph of the continuous-flow artificial heart, and below it, the letters S, M, L and XL. He’d circled the L with a red Sharpie. “Doesn’t that look cool?” he said, holding it up for me to admire. It looked like a novelty item you’d pick up at a magicians’ supply store. “It’s a joke,” he said, “but this is kind of what I envision. That you’ll be able to walk into Costco, pull this off a shelf, and have your surgeon stick it in your chest. These things are so simple, we’ll be putting them in the chests of 100,000 people a year.” He set down the box, picked up the turbines with their dolly dresses, and turned them over lovingly in his hands. Just as human flight wasn’t possible until people gave up the idea of imitating birds, permanently replacing the most vital of organs may not be possible without ridding our minds of the heart’s telltale beat. “I think we’re on the verge, right now, of solving the artificial-heart problem for good,” he said. “All we had to do was get rid of the pulse.”

Dan Baum is the author, most recently, of the book Nine Lives:Mystery, Magic, Death and Life in New Orleans.

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