Heart--A History Page 9
Their machine was, as Gibbon described it, an assemblage of “metal, glass, electric motors, water baths, electrical switches, electromagnets, etc.… [that] looked for all the world like some ridiculous Rube Goldberg apparatus.” It went through numerous refinements through the 1930s, eventually growing to the size of a grand piano. But inelegant as it was, it worked. By the end of the decade, Gibbon could keep cats and dogs alive for several hours and, most important, was able to wean the animals off the machine to resume their own heart and lung function. In 1939, Gibbon published his findings in a paper titled “The Maintenance of Life During Experimental Occlusion of the Pulmonary Artery Followed by Survival.” He later wrote, “I will never forget the day when we were able to screw the clamp down all the way, completely occluding the pulmonary artery, with the extracorporeal blood circuit in operation and with no change in the animal’s blood pressure. My wife and I threw our arms around each other and danced around the laboratory laughing and shouting hooray.” He added, “Although it gives great satisfaction to me and others to know that the [heart] operations are being performed daily now all over the world, nothing in my life has duplicated the ecstasy and joy of that dance with Mary around the laboratory of the old Bulfinch building in the Massachusetts General Hospital.”
Humans are a lot bigger than cats, however; we have roughly eight times the blood volume of a feline. So Gibbon began to think of ways to adapt his machine for human use. His research was interrupted when he was called to serve as a trauma surgeon in the Pacific theater from 1941 to 1945. After the war, when Gibbon returned to his project, major problems still needed to be solved. Blood cells were getting chewed up in the pump. Particles of protein, fibrin, fat, and gas were injuring vital organs. And of course, a larger machine was required to handle the greater blood volume in humans—no longer a soda can but a milk gallon. To help him solve these problems, Gibbon turned to the IBM Corporation, whose chairman, Thomas Watson, was the father-in-law of one of his students. With the aid of IBM’s engineers, Gibbon refined his machine: adding filters to catch clots, increasing the size of the oxygenator, and incorporating special roller pumps. The postwar years were ripe for such research. Large-scale public-private projects were being launched in computing, nuclear technology, and space exploration. Gibbon’s team took advantage of this political environment to essentially compress three billion years of evolution into two decades of intense human endeavor. By the early 1950s, the mortality rate in his animal experiments had decreased from 80 percent to 12 percent, and Gibbon believed the time had come to try his machine on a human being.
Gibbon wasn’t the only scientist working on a heart-lung machine. Between 1950 and 1955, five medical centers were engaged in the pursuit, each with a different design. At the University of Toronto, William Mustard developed a machine that used isolated rhesus monkey lungs to oxygenate the blood. At Wayne State University in Detroit, Forest Dodrill and engineers from General Motors built a heart pump that looked very much like the engine in a Cadillac. At the Mayo Clinic, John Kirklin and his colleagues constructed a heart-lung machine based on Gibbon’s design that used a vertical oxygenator and roller pumps (it was eventually called the Mayo-Gibbon oxygenator). At the University of Minnesota, Clarence Dennis, a colleague of Lillehei’s, developed his own machine based on drawings that Gibbon had shared with him on a visit to Gibbon’s lab. Dennis would be the first to try the heart-lung machine on a human, six-year-old Patty Anderson, who would die on the operating table. His next attempt also failed when assistants let the reservoir run dry, pumping air into the patient’s arteries, killing her instantly. From 1951 to 1953, eighteen patients were reported to have undergone open-heart surgery with heart-lung machine support. Seventeen died.
It is only fitting that Gibbon, who conceived of the heart-lung machine and worked on it longer than anyone else, was the first, and not Dennis, to use it successfully on a person. Gibbon’s first attempt, after decades of animal experiments, proved tragic when the fifteen-month-old baby bled to death as he frantically searched for an atrial septal defect she did not have. (She had been misdiagnosed.) On March 27, 1953, he tried again, this time on Cecelia Bavolek, an eighteen-year-old freshman at Wilkes College in Pennsylvania. She had been hospitalized with heart failure three times in the previous six months. The surgery to repair her ASD took more than five hours. Managed by six assistants and weighing more than a ton, Gibbon’s machine took over the patient’s circulation for approximately thirty minutes while he sewed the half-dollar-sized hole closed with cotton sutures. The operation had an unexpected complication: the machine clogged because it ran out of blood thinner and had to be operated manually. When Gibbon took Bavolek off the machine, he had low expectations. But her young heart restarted almost immediately. One hour after he closed up her chest, she was awake and could move her limbs on command. Her recovery was uneventful, and after thirteen days, she was discharged from the hospital. She went on to live for almost fifty years, dying in 2000 (the year before I started my cardiology training) at the age of sixty-five.
John Gibbon and Cecelia Bavolek beside a heart-lung machine, 1963 (Courtesy of Thomas Jefferson University, Archives and Special Collections)
Though Time proclaimed that Gibbon had “made the dream [of open-heart surgery] a reality,” he was painfully shy and avoided publicity. He posed for a picture with his machine only after Bavolek agreed to join him. In the end, he published the only account of his operation in a little-noticed journal, Minnesota Medicine.
After the Bavolek surgery, Gibbon attempted four more with his heart-lung machine, with poor results. Though his research career was marked by tremendous perseverance and courage, after those four children died under his knife, he lost heart. Unlike Walt Lillehei, who never lost sight of the greater goal, even in the face of surgical deaths, Gibbon could not stomach putting young children at risk, even if it meant giving up on his lifelong project. He decided that his machine was too immature to be used safely and called for a one-year moratorium on its use. He never operated on the heart again. Research on his machine was taken up by universities and private companies. In 1973, he died of a heart attack while playing tennis.
Today heart-lung machines are barely the size of a small refrigerator. Hospitals have full-time staff to operate them. Of course, there are still complications: blood cells get chewed up in the plastic and metal apparatus and patients suffer strokes. A small but significant number of patients have some degree of cognitive impairment afterward, such as memory and attention deficits and language problems, a condition known as “pump head,” which can persist years after surgery and in many cases is probably irreversible. The cause is unclear but may include tiny blood clots or bubbles, inadequate blood flow to the brain during surgery, the dislodgement of fatty material from the aorta, and brain inflammation.
But despite these problems, the heart-lung machine has been indispensable for advancing the field of heart surgery over the past half century, saving countless lives. Open-heart surgery was already the beacon of American medical prowess in the early 1950s, and Gibbon’s invention only quickened the field’s progress. The mortality rate for cardiac surgery dropped from 50 percent in 1955, to 20 percent in 1956, to 10 percent in 1957. By the late 1950s, even the most complex congenital lesions were being repaired. “A physician at the bedside of a child dying of an intracardiac malformation as recently as 1952 could only pray for a recovery!” Lillehei wrote. “Today with the heart-lung machine, correction is routine.” The heart became, as one writer put it, “an object of surgical assault.”
Perhaps my own family history would have had a different trajectory had Gibbon’s invention been ready for my grandfather, who surely had coronary artery disease and almost certainly died of a coronary thrombosis. Alas, the field would have to wait until 1960, when the first successful human coronary artery bypass operation was performed by Dr. Michael Rohman in the Bronx. In 1967, René Favaloro performed the world’s first coronary bypass surgery at the C
leveland Clinic using veins from the leg to bypass the coronary obstructions, the standard technique still in use. Today more than one million cardiac operations are performed annually worldwide—three thousand a day—with the heart-lung machine.
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One of those operations was that valve surgery in Fargo on Christmas Day. It had been going on for more than two hours when Dr. Shah finally cut out the infected valve with a pair of scissors. I’d been standing quietly next to him the whole time, my legs increasingly heavy and sore, wondering when the operation would end. Shah put green-and-yellow Gore-Tex threads, the same stuff in my winter jacket, through the cloth ring holding the prosthetic tissue valve. It was a mess, like the tangled ropes of a parachute, a topological nightmare, but when he slid the new valve down the circular array of stitches, the sutures straightened out and the valve went right into place.
When he was finished, he tipped the head of the table down so if there was any air in the heart, it would travel upward, away from the brain. The perfusionist turned a dial, and the flow of the heart-lung machine slowed. When Shah took the clamp off the aorta, blood started to flow down the coronaries, washing out the potassium solution that had made the heart fibrillate. The heart began to beat weakly, almost in synchrony with the labored breathing of the ventilator. Shah removed the remaining tubes from the chest. Then, with stainless-steel wires, his assistant closed up the breastbone.
We were done. I was so relieved, mostly for the patient but also, I must admit, because I wanted to go home. It was nearly five o’clock in the morning, and I could barely stand. But Shah looked worried. The patient’s blood pressure was 70/40, dangerously low. The heart hadn’t quite resumed adequate function. After conferring with the anesthesiologist, he inserted a helium-filled balloon pump into the aorta to support the blood pressure. With a pained expression, he sat down on a stool next to the still-unconscious patient and waited.
I waited, too, for a while, hoping something would happen so we could call it a night. By then Shah was ignoring me. I went to the locker room to change. Some time later, a nurse woke me up on the hard bench and told me she was going to take me home. We drove quickly along slushy roads coated with what looked like mashed potatoes and gravy. The sun was rising, and the trees along the road carried the weight of several inches of snow that had fallen during the night. She dropped me off at my parents’ house. I went in and immediately crashed.
Shah never called me to tell me what happened, but the next day I heard from my parents that the patient never made it out of the OR. His blood pressure continued to drop, despite the balloon pump and intravenous medications, and around seven that morning, nearly seven hours after we’d arrived at the hospital, he died, another victim of endocarditis, Osler’s great killer. It was an important lesson for me at that early stage in my career. No matter the extraordinary progress that has been made in heart surgery over the past century, the heart remains a vulnerable organ. Despite our best efforts, cardiac patients still die.
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Nut
The contemplation of the period when arterial disease of the heart can be prevented or retarded produces an aura of greatness. Next to food, shelter, and the absence of war, there is probably nothing more important.
—Claude Beck, Journal of Thoracic Surgery (1958)
When I began my cardiology fellowship in 2001, the dingy catheterization labs at Bellevue looked as if they hadn’t been renovated since André Cournand and Dickinson Richards did their seminal work on cardiac catheterization—a procedure used to measure pressures and flows in the heart’s chambers and the coronary arteries—at Bellevue in the 1930s. The paint was peeling, lights had a dusty glow, and angiograms were still recorded on rolls of film—not digitized, as they were at the other major Manhattan teaching hospitals. Rhoda, the stern charge nurse, and her cadre of graying, droopy-lidded assistants—they, too, looked like artifacts of World War II. Rhoda would never tell you what she wanted you to do. It was a lot easier to yell at you after you made a mistake. My first month in the cath lab felt a lot like internship—except now I was in my thirties, married, and seven years into my medical education. If I asked whether a patient needed preoperative blood work, Rhoda or her assistants would act as if I were stupid or arrogant because it was in their protocol, and they had been doing it for years, and shouldn’t I know this, and who was I to tell them what to do? There was so much to see to: take a history and examine the patient; X-rays, bloods, consent, and so on. The rhythm of the day got digitized into tiny to-do boxes, to be filled in at every hour. What motivated the long hours was fear: fear of overlooking something that could hurt a patient, of course, but more immediately fear of rebuke, of being dressed down for mismanagement or an oversight. And so I came to think of my cardiology training as being on dual tracks: learning about the heart, obviously, but also what was in my heart—what I was made of—at the same time.
Dr. Fuchs, the cath lab chief, didn’t ease the tension any with his intimidating stare, his patronizing admonishments to dress like him (blue scrubs, white sneakers only), and his pompous talk of Henry Green and other obscure novelists. The first time I scrubbed in with him, Fuchs went rapid-fire through a series of instructions on how to operate the baffle, a small-keyboard-sized plastic contraption with an array of stopcocks attached to fluid-filled lines that was the nerve center of every catheterization procedure. My hands shook in a fine tremor as he ran through the different ways to open and close the stopcocks to flush the catheter, get rid of bubbles, inject X-ray-opaque dye into the coronary arteries, and so on. “Whatever you do,” he said, tapping on a small white knob, “don’t inject unless you turn this stopcock.” Otherwise, he warned, a dangerous amount of pressure could build up in the catheter. A minute later, he advanced the catheter up the aorta, twisted it around the arch, and with some fine finger movements inserted it into the right coronary artery. “Okay, here we go,” he said, moving the table up and down and side to side, adjusting the position just right under the camera. He stepped onto the fluoroscopy pedal, which controlled the X-ray source that would take pictures of the coronary arteries. It produced a crackling sound, like kindling catching fire. “Inject!” he boomed. I reflexively stepped onto the pedal that released dye. “Stop!” he shouted. “I told you never to do that!” I stood frozen, wondering what I had done wrong. He quickly turned the critical knob to relieve the excess pressure in the catheter. Then, ordering me away from the table, he put one foot on the fluoroscopy pedal and the other on the dye pedal and did the angiogram by himself.
It got easier. I didn’t think it would, but it did. Lucas, a kind senior cardiology fellow, got me a baffle to practice on and methodically, professorially, went through all the knobs and combinations with which I should become familiar. Procedural cardiology, I quickly learned, was a craft; you got better with practice. I’d never been especially good with my hands, but after a few months I was able to do the first half of a cardiac catheterization on my own. The satisfaction I experienced doing an angiogram was something I’d never expected. The procedure became ritual: Lead apron, sterile gown, carefully arranging the instruments we were going to use with the precision of a sushi chef. Then a quick squirt of lidocaine to numb the groin. Needle finds the femoral artery. A burst of maroon fills the syringe. Blood spurts on the sterile drape (and sometimes the stone floor). Guide wire into the artery. Deep nick with a scalpel. Dilate the soft tissue to create a track for the catheter. Push, push. Blood gushing, don’t panic. Catheter slips over the wire, connect it quickly to the baffle. Okay, deep breath, deep breath, here we go …
Like the heartbeat itself, catheterization was mechanical, repetitive; we performed more than a few every single day. Procedural comfort eventually lent a certain balance, confidence, to my fellowship experience. For the first time that I could remember, physical action alleviated my anxiety, providing me with a zone of calmness in which to operate. When I was doing a cath, the world outside disappeared for just a few minutes. The pro
cedure, with me as conductor, was all that mattered. In the cath lab, I was a doer, a craftsman, and not just a thinker. Seeing a plastic tube inside the heart quickly ceased to shock, which, in the end, was the most shocking thing of all.
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For most of history, inserting anything like a catheter into the human heart was considered madness. But things changed on a hot May afternoon in 1929, when a surgical intern named Werner Forssmann and a nurse named Gerda Ditzen tiptoed into an operating room at the Auguste-Viktoria Hospital in Eberswalde, Germany, a small town fifty miles northwest of Berlin. For more than a week, they had been planning a tryst, but not of the carnal kind. Quietly closing the door behind them, Forssmann ordered Ditzen onto a surgical table, where he tied her down, immobilizing her arm. Sweating profusely in the heat, she anxiously awaited his long scalpel, believing, as Forssmann had told her, that she was going to be the subject of an experiment that would change the course of medicine. But Forssmann had a different plan. Turning his back to her, he applied antiseptic soap to his own arm and quickly injected anesthetic into the skin and soft tissue. Then, armed with a scalpel, he sliced open the skin over his elbow pit with an inch-long incision. Droplets of fat and blood, like clusters of tiny grapes, followed the track of his blade.