"Electric Heart"PBS Airdate: December 21, 1999 SPONSOR: During the following program, look for NOVA's Web markers which lead you to more information at our Website. NARRATOR: On April 4th, 1969, Haskell Karp became the first human being to have his natural heart removed and replaced with an artificial one. Surgeon Denton Cooley, known as "the man with the golden hands," performed the historic operation. The experiment vaulted him to fame and captivated the country's interest. DENTON COOLEY [film footage]: The fact that Mr. Karp has regained organ function indicates that the mechanical heart is a feasibility. NARRATOR: But within days, those with the most at stake began to question the experiment. SHIRLEY KARP: I saw apparatuses going into the arms, the hands, the feet. He could not say anything. I don't think that he was really conscious. One day they removed the tube from his throat, they put a sheet over all the apparatuses in back of him, and had the media take their pictures, saying, "look how well he's doing." And immediately after this was done, they put back the resuscitation tube, and opened up everything that they had closed up. NARRATOR: Three days after receiving the artificial heart, a human one was found. But Karp died shortly after it was transplanted. After seven more failed attempts, the public and many doctors lost faith in the idea of replacing the human heart with a mechanical substitute. But now artificial hearts are back, in a new high-tech incarnation. Will they at last fulfill the dream of giving dying patients a second chance at life? SPONSOR: Major funding for NOVA is provided by the Park Foundation, dedicated to education and quality television. SPONSOR: C|Net, bringing the digital age into focus. C|Net.com, the source for computers and technology. SPONSOR: This program is funded in part by Northwestern Mutual Life, which has been protecting families and businesses for generations. Have you heard from the quiet company? Northwestern Mutual Life. SPONSOR: And by the Corporation for Public Broadcasting and by contributions to your PBS station from viewers like you. Thank you. NARRATOR: Glen Manderson is only 32 years old, but he's suffering from chronic heart failure. The muscle in his heart has become so weak it can no longer pump enough blood. Surgeon Mehmet Oz fears Glen will not survive the next 48 hours. Glen desperately needs a new heart, but because of the scarcity of human donors, there is no organ at hand. MEHMET OZ : - recognize that if this was five years ago, we would have nothing to offer you. And so I think that you're much better off now, because we have options that we can use in a pinch, and this is definitely a pinch. NARRATOR: Dr. Oz hopes to implant an electrical pump that can take over the work of Glen's weakened heart. MEHMET OZ: Now you've seen pictures of it. This is what the pump looks like. NARRATOR: It's called a Heartmate VE, and weighs two and a half pounds. MEHMET OZ: I know that it looks big, but it actually fits very nicely inside of you, especially because you've got reasonable size. It would fit in me pretty well as well. It goes under the rib cage, and once it's in, you're not going to be able to see it. EUNICE MANDERSON: Are you going to take the heart out? MEHMET OZ: No, we're not going to take the heart out, the heart stays in, this is a piggyback pump. EUNICE MANDERSON: It's going to be inside of him? MEHMET OZ: It's going to be inside of him. NARRATOR: Because the pump takes over the work of the heart's left ventricle, it's called a "left-ventricular assist device" or "LVAD." It's a direct descendant of the old artificial heart. MEHMET OZ: For some reason, this evolution - because it was that, and not a revolution - snuck up on the American public. And so many times, patients and their families don't know what a mechanical pump is, and they're scared by it. They don't realize that it is a safety net to keep you alive if things don't work out well. And that is a huge emotional barrier to overcome. Most people believe that if you get a mechanical heart it's just delaying the inevitable, and it's not. NARRATOR: That night Glen's kidneys begin to fail from lack of enough blood. Fluid fills his lungs; he has trouble breathing. There is a 30% chance he will not survive his LVAD surgery, but without it, death is certain. MEHMET OZ: When we opened his chest, his heart was so big that it was literally pushing against the chest bone. That's very uncommon. And so we opened the bone with a saw, the heart was right there and got cut. Now, needless to say, not only do you not expect it, but when it happens it's a catastrophe, because you are completely uncontrolled. NARRATOR: Glen is in no condition to lose any more blood. His heartbeat fluctuates wildly. The surgical team quickly channels his blood into the heart-lung machine. MEHMET OZ: OK, you guys ready to go on? I don't care! You ready to go on? Yes! NARRATOR: In minutes, the operation is back on track. The team now focuses on implanting the Heartmate. MEHMET OZ: So this is going to be where the device enters the heart. This is his heart and it's just going to be passive, you know, letting blood flow through it into the device. NARRATOR: Within hours the electrical pump has taken over the work of Glen's heart, sending oxygen-rich blood to revitalize his failing body. MEHMET OZ: Glenroy is a ghost. Five years ago he would have died. Three years ago we probably would have saved him. Today we will almost always save him. That is the rapid degree of change that we've experienced. And what we've really learned, more than anything else, is how to use the machine in the man. That was the next barrier. We could build pumps - that's a pretty trivial issue. But making pumps that you could slip into the human body without the human body knowing that you've done it, that was the big challenge. And that's the battle that we've been able to win. NARRATOR: The LVAD will allow Glen to go home and lead an almost normal life until a donor heart becomes available. His survival is the culmination of decades of struggle to build a mechanical substitute for the most sacred part of the human body. Making an artificial heart to match the abilities of the human heart is a huge technological challenge. BUD FRAZIER: The heart is a remarkable organ, beating over 100,000 times a day, without rest, year after year after year. MICHAEL DeBAKEY: It's a very efficient pump, absolutely. Very efficient. DENTON COOLEY: It's probably the only organ in the body that we can actually feel it work. UNIDENTIFIED MAN: No matter what you do to it, how much beer you drink or how much food you eat, it just keeps going like that - those little battery commercials. JIM AKKERMAN: It feeds itself, it energizes itself. NARRATOR: In a lifetime, the human heart will beat over two and a half billion times, unless it fails. Once the heart becomes injured or diseased, it can no longer pump enough blood. Victims have trouble breathing. Any activity leaves them exhausted. Heart disease is our number one killer, and congestive heart failure is on the rise. STEPHEN WESTABY: As the population gets older, the incidence of heart failure increases dramatically, and really, there is an excellent treatment for end-stage heart failure, and that is heart transplantation. But because there are not enough donor hearts, that's only available for a very small proportion of those patients. Having a realistic artificial heart is a very important contribution. NARRATOR: Dr. Michael DeBakey is a pioneer of the artificial heart. In the 1960s he was one of a handful of leading heart surgeons. Known as the Texas Tornado, he both inspired and terrified those around him. MICHAEL DeBAKEY [film footage]: What do you mean, "it's not flushing"? No, no, no, no, no. Put your finger over that. You're not concentrating, you're watching me. BUD FRAZIER: Dr. DeBakey was quite a task master. It was like working under a Marine drill sergeant. He was very tough, he expected actually much more of you than you could actually do. NARRATOR: Outside of surgery, DeBakey was working with a team of researchers at the Baylor Medical College in Houston to develop an artificial heart which would replace the natural organ. MICHAEL DeBAKEY: We were thinking of the heart as just a pump, and it seemed logical that if that's the main function, you ought to be able to duplicate that mechanically. NARRATOR: Placing a man-made heart in a human has always raised disquiet. The history of the artificial heart is rife with contention. STEPHEN WESTABY: There's been enormous controversy surrounding any artificial heart implant. I think part of the problem is that many of the operations have just been isolated, one off incidents that other physicians have been able to refer to as experimental. Are we playing with the patient? NARRATOR: In the 1960s, DeBakey's team was testing his artificial heart in animals. The principal researcher, Domingo Liotta, went to Dr. DeBakey with a startling proposition. MICHAEL DeBAKEY: Dr. Liotta was very ambitious to apply the pump in humans, and I explained to him that we couldn't do that because it had been used in seven calves, four of which died on the operating table. We couldn't go and get approval from our committee. I didn't realize that secretly he went to see Dr. Cooley about it. NARRATOR: Denton Cooley was one of Dr. DeBakey's protégés and colleagues, who also worked part time at the nearby Texas Heart Institute. He seized the opportunity that the more cautious DeBakey wasn't prepared to take, to do the first human trial. MICHAEL DeBAKEY: Now Dr. Cooley had no experience with the artificial heart program at all. He didn't do any laboratory work. He was a good surgeon, but that's all. DENTON COOLEY: Dr. DeBakey seemed to show little interest in ever using it, and Dr. Liotta thought he was just wasting his years in a laboratory working with animals and so on, that this would never be tested clinically. And I thought, and agreed with Dr. Liotta, the time had come to really give it a test, and the only real test would be to apply it to a dying patient. NARRATOR: The patient was Haskell Karp from Skokie, Illinois. He was a man with a long history of heart problems. On April 4th, 1969, Haskell Karp's own heart was completely removed and replaced with an artificial one. Denton Cooley had not sought any approval for this ground-breaking operation. DENTON COOLEY: Well, in those days, I didn't feel like we needed permission. I needed the patient's consent, that was essential of course, and I think if I had sought permission from, say, the Federal Agency, or the hospital or something, anybody else, I think I probably would have been denied, and we would have lost a golden opportunity. MICHAEL DeBAKEY: I was in Washington when I read in the morning papers there about the use of this artificial heart that Dr. Cooley had put in a patient, and I was shocked. I didn't know that he had done all of this surreptitiously. You see, I didn't know he had taken it from the laboratory. DENTON COOLEY [film footage]: We are most encouraged by our results so far, and even if Mr. Karp goes nothing - doesn't go any more than another day, I think that we have demonstrated that there is validity to this concept of making every effort to prolong life at any cost in order to make possible a cardiac transplantation. NARRATOR: Two days after the operation, with Karp growing worse by the minute, his wife made an emotional appeal for a human heart. SHIRLEY KARP [film footage]: I see him lying there, breathing, and knowing that within his chest is a man-made implement where there should be a God-given heart. NARRATOR: Within a day, a donor heart was found. But Haskell Karp died from infection shortly after receiving it. MICHAEL DeBAKEY: Dr. Cooley's justification was he was trying to save the life of this patient. But you know, you don't take an experimental device to save the life of a patient that has had no evidence that it would do that. NARRATOR: There were no more human trials until the early 1980s, when a new figure suddenly entered the race. Until his father died of heart disease, Robert Jarvik had planned to become an architect. He then switched to medicine and engineering. By 1982 Jarvik was conducting animal trials at the University of Utah with an artificial heart he called the Jarvik Seven. ROBERT JARVIK: The Jarvik Seven heart was a total heart, completely replaced the natural heart in the chest, and is driven with compressed air. So if you look inside the heart here - see the diaphragm move? NARRATOR: Jarvik's team was one of five in the U.S. working on artificial hearts. With funding tight, he decided the time was right for a high profile human trial. THOMAS PRESTON: Here was a whole section of the university that had done a lot of work, good work, to get to this point, and they were in danger of losing their financing. And they knew that they needed something big. NARRATOR: Once again, a volunteer was needed, someone too ill for a transplant and large enough to receive the Jarvik Seven. Someone like dentist Barney Clark. THOMAS PRESTON: It's interesting and important that the team called it "necessary therapy." If they had said, "Well, we don't know how long he'll live," then it would have been in the realm of experimentation, and it wouldn't have been approved. NARRATOR: Haskell Karp's artificial heart was temporary, meant to keep him alive while he waited for a transplant. But the Jarvik Seven was intended to stay in Barney Clark's body for life. ROBERT JARVIK: That intention, symbolically, is part of the thing that brought so much attention to the Barney Clark case. ROBERT JARVIK [film footage]: The patient is now in the process of having his chest closed, it's almost completed. Most, if not all, of the functions being monitored are stable. NARRATOR: The full realization of what they had done surprised even some members of the surgical team. DONALD OLSEN: Here was a human being, alive, conversant, supported on a mechanical device. He had no heart. He had no conventional, traditional heart. And you know, the poets and writers have always said that the heart is really the center of love and personality and so forth and so forth. And he had none. WILLIAM DeVRIES [film footage]: And it was a really - almost a spiritual experience to everybody in the room. DONALD OLSEN: This mechanical device couldn't be the seat - possibly be the seat of love and respect and honor. It was a polyurethane. MEDIC AT CONFERENCE [film footage]: This morning, which was five hours into his 13th day - ROBERT JARVIK: There was this human drama that was almost like, like a serial, almost like a soap opera: what's going to happen tomorrow? MEDIC AT CONFERENCE [film footage]: - Dr. Clark had a sudden drop in his blood pressure. He kissed his wife and was taken to surgery. THOMAS PRESTON: One of the valves broke. It then came out that they had never tested that particular valve in the setting of an artificial heart. ROBERT JARVIK: There were a few somewhat weak links in the system. We had to reoperate and replace that one half of the heart. WILLIAM DeVRIES [film footage]: What does it feel like to have an artificial heart in the chest? Do you have pain, or is it uncomfortable? NARRATOR: Three months after this weak link was repaired, Barney Clark was able to face the media. BARNEY CLARK [film footage]: Something you get used to is, I imagine, this pump - WILLIAM DeVRIES [film footage]: The noise of the pump? BARNEY CLARK [film footage]: - but you get used to that. WILLIAM DeVRIES [film footage]: Does that bother you much at sleep, when you - BARNEY CLARK [film footage]: No, it doesn't bother me at all. Even when I'm awake it doesn't. THOMAS PRESTON: Well, after the operation he had almost no quality of life. He had a negative quality of life. He had bleeding from his nose, and he required surgery on that. He had innumerable tests. BARNEY CLARK [film footage]: Well, I tell 'em that it's worth it - there's no alternative, they either die or they have it done. DONALD OLSEN: Many days he did not enjoy; but many days he did enjoy the communication with his very attentive wife, and he felt genuinely that he had made a contribution. BARNEY CLARK [film footage]: A pleasure to be able to help people and maybe you folks'll learn something. MEDIC [film footage]: Last night we lost a very dear friend, one of the greatest pioneers. THOMAS PRESTON: The value that we got out of that experiment, and that's all it was, was that it was not fit to be used at that time. MICHAEL DeBAKEY: We realized this was a much more complicated problem than it first seemed, and after we had worked for almost 20 years, I really came to the conclusion that it probably is best to quit working on the total artificial heart. NARRATOR: DeBakey, Jarvik and other researchers focused their efforts on perfecting simpler pumps called LVADs - pumps that would assist the heart rather than replace it. DeBakey had been the first surgeon to use an LVAD in the operating room. The device remained outside the patient as a temporary support until the natural heart recovered from the shock of surgery. As the technology progressed, researchers worked on developing devices that could move from temporary to long-term support for the heart's left ventricle. The biggest challenge was to create a pump that did not cause strokes. These white blood cells have detected a minute flaw in the surface of this glass. As they attempt to smooth out the defect, dangerous biological deposits accumulate that might break free and pose the risk of blood clots. Finally, medical engineers found a solution. MEHMET OZ: After years of trying to overpower Mother Nature, the tack was changed, and we said, "Let's allow you to coat your blood cells over a very rough surface, a surface so rough that once your blood sticks to it, it can't come off again." In fact, that's what happens. These devices, when you take them out after a few days, are completely covered by your cells. And that's the reason we've seen such a low stroke rate with these devices, we believe. NARRATOR: Only one completely implantable device, called the Heartmate, used this approach. Soon it dominated the market. Using this new technology, hospitals could keep patients waiting for a transplant alive for months, even years. Still, LVADs were seen only as a bridge to transplant, until a series of cases forced doctors to rethink their ideas. In September 1994, Norbert Hilbert was rushed to the Berlin Heart Institute, suffering from a viral infection in his heart. NORBERT HILBERT [voice over translation]: He told me my illness was very serious and that I could have this assist device while I was waiting for a transplant. Otherwise my chances of survival would be two, three, or five days at the most. MATTHIAS LOEBE: This x-ray shows us the situation at two days, actually, before we placed him on the assist device, and what you can see is that the lungs are congested with fluids which cannot be transported by the failing heart. You also may see that the heart itself, which is here, is quite enlarged, and we decided to implant the assist device. NARRATOR: With their patient hospitalized for nine months, supported by an LVAD, the Berlin doctors noticed something unexpected. They approached him with a choice. NORBERT HILBERT [voice over translation]: Dr. Mueller said, you could have a transplant - we have an organ for you. But against all expectations, your own heart has recovered considerably. So it is possible your heart may recover to such an extent that we may consider removing the assist device. R. HETZER: I was very hesitant to think about explanting such a life-saving pump in such a patient. MATTHIAS LOEBE: This x-ray shows us the situation after explantation. You clearly see how the lungs have improved, they are darker now, which means there is no fluid anymore. But in particular, if you look closely, you see that the heart itself has shrinked considerably between these two pictures, and it's more or less normal size of a human heart on this x-ray. NARRATOR: Three years after his LVAD was removed, Hilbert's natural heart is functioning as well as ever. STEPHEN WESTABY: What happens when you put an LVAD into the left ventricle is that there is no longer pressure within that heart chamber, and completely rests the left ventricle. And what chronic rest does is allow the very much enlarged heart cells to go back to normal size. If you intervene early enough, you'll start to get that heart failure process to reverse. NARRATOR: Yet the majority of LVAD patients have hearts that are too damaged to recover. Patients like Peter P., whose first heart attack destroyed 80% of his heart muscle. Saved by a Heartmate, he now must wait with 50,000 other Americans for a transplant. Patients like Peter, living months or years on LVADs, exemplify both the hopes and limits of the current technology. PETER P.: In a way, it gives you a certain amount of freedom, because I can get up, walk around with this battery pack, go visit people, and virtually have a certain amount of freedom. But it's also very constraining, because you're at the mercy of the clock. Batteries last about four and a half hours. So I'm constantly checking a little LED that I have to let me know how much power is left, and it becomes very stressful. MEHMET OZ: Because the batteries are large, we are forced to have a line that goes between the battery and the device, and penetrates the skin. This so-called percutaneous line is the Achilles' heel of this technology, because the line is rigid and the patients, as they move around and live their lives, rough up the line, and it tends to tear the skin around the connection, and then it gets infected. NARRATOR: The drive line also vents air displaced by the pulsing of the pump, creating a loud swishing noise that disturbs patients. But despite these difficulties, Peter is fortunate that he is large enough to have a battery-powered LVAD fit into him. For small women and children in heart failure, the only available assist device to keep them alive is one that remains outside their bodies. Attached to large consoles, these patients remain bedridden while they wait for a transplant. MEHMET OZ: These pumps that you're seeing today are the Model Ts of this industry. They're the first generation, they're the proof that this technology can work. And now that we have that evidence - that psychological barrier has been crossed - we can start to move at a very fast speed towards permanent devices that really are designed to be elegant, simple to implant, and easily available for everybody who needs them. NARRATOR: As scientists struggled to develop smaller blood pumps, they began to question whether they had to be pulsatile, mimicking the pumping action of the natural heart. Humans need a pulse so that the heart can rest between beats and absorb the energy it needs to pump blood. But if the natural heart needs time to rest, a mechanical pump does not. One researcher began to work on an LVAD that was not pulsatile. His name was Richard Wampler. RICHARD WAMPLER: There were a few scientific reasons why I believed you might not need a pulse. It is true that if you go out into your arm, when you go to the doctor that you can feel your radial artery and you'll feel a pulse, but when you go out on the capillary level, by that time, the pulsatility is totally damped, so really at that level the flow is continuous flow going through these capillaries. NARRATOR: Wampler developed a tiny axial flow pump that could temporarily assist the heart. An axial flow pump works by spinning an Archimedes' screw which draws fluid in through one end, then sends it out the other. Through it, blood would flow continuously - without a pulse. In 1988, after two years of animal work, surgeon Bud Frazier used the pump in a dying transplant patient who could not be assisted with a conventional LVAD. RICHARD WAMPLER: I was extremely anxious because I'd never placed one in a human and I wasn't sure if it would really even go up the arteries because they're diseased arteries, the animals are healthy. I didn't know if there was something about the human anatomy that it wouldn't go into the heart like it was supposed to, but it all went perfect. NARRATOR: The pump allowed the weakened heart to rest long enough to recover. Over 100 more patients who could not use standard LVADs were saved. This echocardiogram shows how the blood, seen in color, is sucked out of a passive heart and circulated. BUD FRAZIER: That was a very dramatic thing because it showed us that, number one, patients could live without a pulse - I had one little boy that lived for about three days without a pulse at all. He was very small, and this small pump could take over his entire circulation. He woke up, he ate Popsicles and he did very well until his heart had recovered enough to start beating. NARRATOR: Although the device could only pump a small amount of blood, it was enough to sustain a resting patient. ROBERT JARVIK: And the thing that was astonishing to everybody in the field was a high-speed rotary pump with little blades that looked like a blender doesn't chew the blood to pieces. So then the job was to make a pump of that general type, meaning an axial flow pump, that could be supported in such a way that it could run indefinitely. NARRATOR: Wampler's pump could only be used temporarily because it needed a constant infusion of liquid glucose to lubricate its moving parts. Robert Jarvik proposed the bold idea of using the blood itself as a lubricant. Around the world, researchers took up the challenge - the goal was to develop a permanent axial flow pump that was small enough to be implanted in the chest, but powerful enough to push blood through the thousands of miles of vessels in the body. Dr. DeBakey turned to NASA for help. MICHAEL DeBAKEY: I did a heart transplant on a NASA engineer by the name of David Saussier, and he did well, and he was very grateful and became interested in what we were doing with the artificial heart. So we showed him. JIM AKKERMAN: It was interesting, the day they showed up, there was two great big limousines came, and there were six doctors in each of the limousines, and they, they had on their pinstriped suits, and there was the doctor of hematology and the doctor of hemodynamics and the doctor of hemo-this and hemo-that. And they brought a big box full of blood pumps that they had worked on, all of 'em had gears and electric motors, and I'm a mechanical engineer and it just made my heart go pitter pat to see all of this machinery. NARRATOR: No one had more experience with axial flow motors than NASA. It's the system used to fuel the pumps of the space shuttle's main engines. NASA agreed to help DeBakey make a permanent axial flow pump at a fraction of the size of the current pulsatile devices. JIM AKKERMAN: I remember I spent most of the Christmas holidays at my computer designing the pump blades for this thing, trying to get the flow, the diameter and the length and all in the ball park. NARRATOR: The collaboration with NASA resulted in a prototype pump the size of a thumb. Inside a person it would create no pulse, just a constant flow of blood. BOB BENKOWSKI: Essentially this pump has just one moving component, and this is the inducer/impeller. What makes this unique is the fact that we embed magnets inside of each one of the impeller blades. And the whole idea is, now, in addition to being the pumping component of the pump, it also becomes the rotor of an electric motor. So what we do is we spin a magnetic field around the impeller and as it spins, it drags this impeller with it. This impeller sits inside of this titanium body, suspended at both ends by ceramic bearings, and this coil here spins a magnetic field, and it spins the pump at about 10,000 rpm, drawing the blood in, propelling it out the back at about five liters per minute. NARRATOR: But adding magnets affected the shape of blades. If the design was not perfect, blood cells could be damaged. BOB BENKOWSKI: The best analogy I can think of is pumping blood is like pumping a whole bunch of water balloons that are suspended in a liquid. You're trying to pump these water balloons without having them rupture. The biggest achievement came through the computation of fluid dynamics at NASA. With their Cray super-computers, they could actually model the flow fields inside the impeller. Very small or subtle changes to the geometry of the pump, for example, a change of 10 or 20 thousandths of an inch in a critical area of the pump would have a drastic effect, because what you would do is you would create localized areas of high pressure or low pressure, producing blood damage that is clinically unacceptable. NARRATOR: After much trial and error, DeBakey's team approached their goal: designing magnetic blades which rotated so fast that blood cells weren't damaged at all. BUD FRAZIER: It's sort of like passing your finger through a candle, you know, the - that you learn as a child to - it's a trick, if it goes fast enough it doesn't burn your finger. NARRATOR: DeBakey now had his working model of a miniature LVAD. MICHAEL DeBAKEY: And you see, there's the heart, and there's the pump. By taking blood from the left ventricle, this is the outflow graft, so blood is flowing from the pump and into the ascending aorta. Now, the electrical connection here for the motor stator would come out and would be attached through the skin to the controlling device which you see here. So this is the battery, and this is the controller, with a belt on the patient, that's all they would need. NARRATOR: But DeBakey was not alone in the race to make a tiny LVAD. In Manhattan, Robert Jarvik was nearing completion of his own axial flow pump, the Jarvik 2000. Working independently, Jarvik has now perfected his own designs and carefully supervises each detail of the machining. Jarvik's pump is so small, it can be placed inside the heart. ROBERT JARVIK: The blood pump is implanted inside the tip of the heart, so if there's a model of the heart, it fits here in the tip of the left ventricle. This whole part here is inside and surrounded by blood, and then the blood that's coming into the heart, coming back from the lungs, is pumped through the opening into the heart, down through the pump and then through a tube back to the aorta. NARRATOR: Placing the Jarvik 2000 inside the heart allows blood to flow directly into the device. The only tube attached to the pump is one that exits the heart. By getting rid of the inflow tube, Jarvik has eliminated a place where blood clots usually form. ROBERT JARVIK: Well, when we started achieving the types of long survivals that historically in this field of research is about the best that can be done with any kind of pump, which means having an animal live about six months. And those devices were clean , we didn't have any complications, we didn't have infections, we didn't have blood clots, we didn't have thromboembolism, and we were very happy about that. OK, let's just put it right here. NARRATOR: Jarvik is ready to use his LVAD in humans and has applied for FDA approval. MICHAEL DeBAKEY: I don't know what stage his device is in. I'm sure that he's trying to compete, too. Yeah. But that's good. NARRATOR: In Houston, DeBakey watches his device take shape at the manufacturing site. DeBakey's LVAD is now a business proposition financed by a company, MicroMed. ROBERT JARVIK: If you compare it to a prize fight, who throws the punch first is not so important as who's there at the end and who throws the punch last. NARRATOR: Instead of seeking FDA approval, DeBakey has come to Europe to oversee the trials of his new LVAD. The operations will be conducted in both Berlin and Vienna, where regulations governing clinical trials are less cumbersome than in the United States. Six seriously ill patients have been selected. JOSEF PRISTOV [voice over translation]: It is difficult when I exercise, my heart hurts. It's like a shock running through my body. RUDOLF HAUER: When I climb stairs, I have to go really slowly and I come out of breath. And so I decided to take this. MICHAEL DeBAKEY: We're coming near the end of the odyssey. It's gratifying in being able to extend the normal life expectancy of patients with chronic heart failure. NARRATOR: DeBakey's pump is the first of the newest generation of tiny LVADS to be implanted in humans. As it takes over the work of the human heart, hopes are high. GERMAN MEDIC: And the system works excellent. No problems. NARRATOR: The team waits for the results. The first patient, whose condition was critical at the time of the operation, died six weeks later. The second had his device removed when a clot caught up in the mechanism. A third patient was switched to another device due to a connector failure. The remaining three patients, including Josef Pristov and Rudolf Hauer, were successfully supported for up to three and a half months until transplantation. Seven more devices have been implanted, but only three worked long enough to carry the patients to transplant. The doctors are not allowed to discuss the results. ROBERT JARVIK: There is so much to be done that everybody's effort will have a place in the treatment - the successful efforts. The issue is that the artificial heart will never be used on a widespread basis until it's so good that the quality of life and the safety and the durability can be taken for granted. NARRATOR: When the newer generation of miniature LVADs are commercially available, small patients in heart failure may hopefully resume normal lives. But what about individuals whose hearts are so damaged they cannot be supported by an LVAD? Patients who are so sick they will not survive the necessary months until a human heart becomes available? Could the dream of a totally artificial "replacement" heart, once heralded as the "Dracula of Medical Technology," be resurrected? Haunted by the image of Barney Clark's suffering, most Americans had decided the technology just wasn't worth it. DAVID LEDERMAN: Because of the publicity, and perhaps exaggeration, by some, as to what that technology promised at the time, it actually set back the field of artificial hearts, because it left people who were very hopeful about this technology discouraged about the technology. This should have never happened. It was a very, very important pioneering effort. There were setbacks, but much was learned. And in fact, those systems are implanted in a few patients every year today, as a bridge to transplantation. And these patients are doing very well. NARRATOR: Each time the Jarvik Seven heart was implanted, doctors learned how to better manage anti-coagulant drugs and reduce the risk of strokes. Since 1993, 147 patients have been supported by Jarvik's original artificial heart. Like Clark, they were unable to leave the hospital. But 88 of these pioneers survived until they got a transplant. Spurred by technological advances and new insights into how the body works, a small group of engineers has labored for decades to perfect a "total replacement" artificial heart. It's a two-pound electromechanical pump called the AbioCor. DAVID LEDERMAN: In the 21st century we now know that operations that used to be very complex, like cataract operations, are today done with a laser, and the patient within 24 hours can see better than they did when they were younger. Now we know also that the wear and tear of the bones can be overcome in some cases by the replacement, orthopedic replacements. So the question is, why is the heart any different? Why should life end because the heart is wearing out? NARRATOR: In a laboratory outside of Boston, an AbioCor quietly pumps away in a tank of salty water. The salt mimics the corrosive effects that blood will have on the titanium and plastic-like materials. To receive FDA approval, this artificial heart must pump 200 million times without failing, enough to sustain life for five years. The challenge is daunting: a human heart beats 100,000 times a day. Commercially available plastic will crack if it's flexed that many times. Scientists had to invent a new material, capable of bending 40 million times a year for 20 years - without breaking. But how will the artificial heart work in a biological environment? At Texas Heart Institute, animals with the device appear healthy, with no evidence of strokes. Unlike Jarvik Seven patients, who were attached to a 350-pound console, this calf can walk untethered, its AbioCor temporarily powered by an internal battery. BUD FRAZIER: You know, one of the beautiful things about the ABIOMED heart is that it is so quiet. I remember our first animal that did well and was up and standing and eating, I got Dr. Cooley to come down and look at the animal. And he came down and looked at the animal and listened to it. And he thought we were tricking him because he didn't even think there was a - he thought it was the animal's own heart. NARRATOR: Unlike the human heart, where both ventricles pump blood simultaneously, the chambers in the AbioCor alternate. When the left fills with blood, the right side absorbs the displaced volume needed to create a pulse. This design eliminates the need for tubes piercing the skin to vent air. BUD FRAZIER: If you can solve that problem, then the transmission of energy across the skin without going through the skin - that's been available for years. So there can be a small coil inside the body, and a small coil on the outside, and this coil can give energy through the skin. MEHMET OZ: You then would wear a belt, and on the belt would be a circular space that would fit over the coil that's inside your body. You would plug batteries into that belt and it would charge the internal component up. That would allow you - if the technology improves as we suspect it will - to charge yourself at night while you're asleep, and then during the day you're untethered. You can go and do anything you want, with no restrictions whatsoever. NARRATOR: At five hospitals around the country, surgeons are preparing to implant the total replacement heart in humans next year. Robert Jarvik once wrote that the artificial heart must not only be "dependable," but "truly forgettable." Will this artificial heart allow dying patients to resume normal lives? Only human tests will yield the answer. MEHMET OZ: We have developed these technologies in animals and with water. When you put them into man and let him go drink or exercise and stress himself in all the ways we know we can, you have to re-evaluate everything from scratch, because they're not going to work all the time. But if we interpret every failure of a mechanical device as a failure of the program, of another proof that these devices can't work for mankind, we'll never get to the results that we desire. NARRATOR: Today mechanical devices save dying patients who await a transplant. But there are 50,000 people on the transplant list and only a fraction will receive a heart. DAVID LEDERMAN: When you use technology to support a patient who will ultimately receive a donor heart, you are not really increasing the number of people whose lives are being saved. We have 2,000 hearts in the United States every year that become available, and we will save 2,000 patients even if we didn't have any assist device. We are not increasing the number of human lives that are saved. And from the societal point of view, this is not a solution. ROBERT JARVIK: So, the most important thing is to make a device that ultimately can be a permanent heart for widespread use in tens of thousands of patients, that's what's needed. NARRATOR: If a weakened heart can be successfully assisted by an LVAD, no surgeon would take the radical step of removing it. But for patients whose hearts are beyond repair, who will never get a transplant, the total replacement heart may be their only hope. SPONSOR: Today there is hope for patients who need other artificial body parts, from livers to skin, even arteries. Explore the potential of the high tech human on NOVA's Website. SPONSOR: To order this show, or any other NOVA program, for $19.95 plus shipping and handling, call WGBH Boston Video at 1-800-255-9424. SPONSOR: NOVA is a production of WGBH Boston. SPONSOR: Major funding for NOVA is provided by the Park Foundation, dedicated to education and quality television. SPONSOR: This program is funded in part by Northwestern Mutual Life, which has been protecting families and businesses for generations. Have you heard from the quiet company? Northwestern Mutual Life. SPONSOR: C|Net, bringing the digital age into focus. C|Net.com, the source for computers and technology. SPONSOR: And by the Corporation for Public Broadcasting and by contributions to your PBS station from viewers like you. Thank you.
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