New Directions for Cardiac Surgery and for Baylor, 1963-2008
By the early 1960s, DeBakey had put Baylor and Houston at the forefront of cardiovascular surgery. He was becoming the best-known surgeon in the world, and patients came to him from all over. Part of this was due to DeBakey's outstanding successes in treating vascular disease; the rest could be credited to his administrative skill in attracting talented faculty and students, and in raising funds for the growing medical center's activities. The 1960s and early 1970s were crucial years for both surgical innovation and the transformation of Baylor and its affiliated institutions. In surgery, DeBakey did the first successful coronary bypass operation, developed and implanted one of the first left ventricular assist devices, championed the establishment of NIH's artificial heart program and developed the first total artificial heart to be implanted in a human patient, and was one of the first surgeons to do heart transplants.
Coronary Artery Bypass Operations
As the boundaries of vascular surgery expanded, DeBakey and others had been doing animal experiments to develop techniques for bypassing or replacing occluded coronary arteries, which supply the heart muscle. (Then, as now, heart attacks, caused by blocked coronaries, were a leading cause of death.) David Sabiston at Johns Hopkins attempted a coronary bypass in 1962, but the patient died of a stroke several days later. In November 1964, DeBakey, with H. Edward Garrett and E. W. Dennis, performed the first successful bypass operation, using a segment of leg vein to re-establish full blood flow. DeBakey did not report that case or his subsequent ones for seven years (as with the first carotid endarterectomies, he wanted to do follow up studies to assess the long-term value of the procedures.) René Favaloro at the Cleveland Clinic introduced a similar procedure in 1967, and was for many years credited with doing the first bypass operations.
Early LVADs and Total Artificial Hearts
DeBakey and others, such as Willem Kolff and Adrian Kantrowitz, recognized that heart lung bypass machines were just the beginning of a technological revolution in cardiac care. There was a clearly a need for temporary ventricular assist devices. Early experience with heart-lung machines had shown that some patients needed circulatory support for a time after the operation was completed, because their hearts wouldn't resume normal function right away. In other cases, it was clear that temporary assistance might help patients recover from cardiac failure if the heart muscle wasn't too badly damaged. During the 1950s, DeBakey established a machine shop at Baylor to maintain and modify heart-lung machines, and to support the fabrication of heart pumps. DeBakey's first left ventricular assist device (LVAD) was implanted in a patient who suffered a heart attack following an aortic valve replacement in 1963. The patient died after several days, although the pump performed well.
Encouraged by the progress in LVAD development, DeBakey and others also began designing total artificial hearts. In the era of technological optimism generated by America's successful space program in the early 1960s, it seemed increasingly possible that, with sufficient expertise and funding, commercial models might be achieved within a decade. Like space flight, development of a mechanical heart seemed to be essentially an engineering problem. If the resources of private industry could be marshaled under a dedicated federal program, the major difficulties--reliable pumps, implantable power sources, and, for all components, materials compatible with blood and other tissues--could be resolved. And the need for such devices was great--despite decades of steady progress in medicine (including cardiovascular surgery), heart disease still caused hundreds of thousands of deaths each year. In 1963, DeBakey testified to Congress that experimental work on artificial hearts looked promising, and recommended special funding for such projects, and the Advisory Council of the National Heart Institute (now the National Heart, Lung, and Blood Institute), subsequently recommended that NIH prioritize the development of an artificial heart. With initial Congressional funding in 1964, the Artificial Heart Program was established, and six companies were contracted to assess the feasibility of an implantable artificial heart from an engineering standpoint. The summary report of these studies, released in 1966, recommended a systems-oriented effort to develop "a family of temporary emergency devices, long-term partial heart replacement devices, and total artificial hearts."
Accordingly, the NIH master plan for the artificial heart called for competing private firms to design, test, and develop component parts and materials for the devices, along with specifications for hardware, installation facilities, testing, and training facilities, by the end of 1967. During the next phase, to be completed by the fall of 1969, the winner of the initial competition would carry out the actual design and development of a number of artificial heart prototypes. In the final phase, the specifications would be completed for mass-production, installation, and maintenance of artificial hearts by 1970. This timetable soon proved to be wildly optimistic. The program foundered during its first few years for many reasons. NIH director James Shannon, though publically supportive of the initiative, was skeptical of the narrow focus on the total artificial heart, and modified the program so that half of its funding could be used for other cardiovascular research, leaving less for engineering work. As time went on, the program's effectiveness would be compromised by waning enthusiasm among legislators, smaller federal budgets, and administrative mismanagement.
Nevertheless, DeBakey made substantial progress with his LVAD and artificial heart development. With his first Artificial Heart Program grant, he invited scientists from departments of electronics, chemistry, hydraulics, and engineering at Rice University to collaborate with his Baylor team. In 1966, he was the first to successfully use an LVAD to wean a patient from a heart-lung machine after surgery. Adrian Kantrowitz, at Maimonides Hospital in Brooklyn, also implanted an assist device in two patients that year, with some success. Despite hopes that these could be used for long-term support of weak hearts, both devices had shortcomings and were ultimately used as a "bridge" support for patients awaiting transplant. During the next several years, DeBakey's team also produced a biventricular total artificial heart prototype. Like other researchers in the field, they encountered many problems in their animal experiments using calves. The devices would sustain the animals for a few weeks, but did not return them to full functioning. Although DeBakey never felt his artificial heart was ready for human trials, in 1969 his colleague Denton Cooley acquired one of his prototypes, modified it, and implanted it in a patient, to keep him alive until a transplant could be done. (It worked, but the patient died soon after the transplant.) DeBakey accused Cooley of unethical conduct (he hadn't authorized the use of the artificial heart), and the breach caused by the incident lasted for decades.
DeBakey was also one of the small group of surgeons worldwide who performed heart transplants in the year following Christiaan Barnard's historic operation in December 1967. His first transplant, performed in August 1968, was part of the world's first multiple-organ transplant effort. Under DeBakey's supervision, five surgical teams at Methodist Hospital transplanted the heart, lungs, and kidneys of a female gunshot victim to four different recipients. Like other cardiac transplant surgeons, DeBakey found that patients often survived the operation only to die weeks later as their bodies rejected the new heart. Recognizing that heart transplants would not be a good treatment option until the immunological problems were solved, he stopped doing these operations and encouraged his colleagues to wait. When the immunosuppressant drug cyclosporine became available in the late 1970s, reducing the incidence of organ rejection, DeBakey and other surgeons resumed performing transplants.
DeBakey had been an early pioneer in filming surgical operations and in May 1965 he performed the first surgery to be televised by satellite. NASA's space program launched the first trans-Atlantic satellite, Intelsat 1, in April, to provide direct and almost instant contact between Europe and North America. NASA asked DeBakey to demonstrate what could be done with it. He performed an open-heart operation that was televised to an amphitheater at the University of Geneva, where monitors allowed the observers to talk to DeBakey.
Further Changes at Baylor
DeBakey's many surgical accomplishments--and those of his talented students and colleagues--and his growing influence in professional and political circles brought Baylor needed prestige. With such international recognition, it was increasingly able to attract better faculty and staff for other departments that had lagged behind, such as Medicine, Anesthesiology, and even Cardiology. Baylor's primary teaching hospital, Methodist Hospital, had also benefited from DeBakey's efforts. He played a key role in raising funds for the hospital's expansion, often through the philanthropy of grateful patients. The medical school, by contrast, was having financial troubles by the mid-1960s. As part of a Baptist institution, it operated under the Baptist General Convention, which required that all its trustees be Baptists. Other philanthropists, unable to serve on Baylor's board, often chose to donate their money elsewhere. Between 1965 and 1968, the chairman of the medical school board aggressively pressured the faculty to somehow force the Methodist Hospital to make up the school's deficit. This tactic drove away several deans and many department chairs, and the school seemed in danger of collapse. The chair finally resigned, after a failed attempt to force DeBakey out. The new chair and DeBakey (who had been appointed Chief Executive Officer) proposed that Baylor University College of Medicine separate from the university, so that their board of trustees could include the most influential people in Houston and could more easily raise money. Baylor University president Abner McCall concurred, and the state soon chartered Baylor College of Medicine as an independent institution. As such, it was also able to get funding from the state of Texas, which was asking medical schools to double their output to remedy a physician shortage. The larger student body and faculty, coupled with the excellent programs in surgery and other specialties, made Baylor much more competitive academically. DeBakey served as its president from 1969 to 1979, and as Chancellor and Chancellor Emeritus afterwards.
During this period, DeBakey continued his medical and surgical work, and established and directed the first (and only) National Research and Demonstration Center in Cardiovascular Medicine. Funded initially in 1975 with a $13.3 million NIH grant, this was a multidisciplinary attack on heart disease that would coordinate basic and clinical research with public and professional education, bridging the gulf between medical research and community health practices. It would also demonstrate innovations in health care delivery and education, which could later be replicated in other parts of the country. The grant ran through 1984, and rather than discontinuing research when the grant expired, Baylor named the project The DeBakey Heart Center and raised funding from private sources. In 1987, NIH awarded Baylor a $14 million, five year grant and re-established the center's demonstration status. Although the center has not yet achieved DeBakey's ultimate goal--"putting ourselves out of business" through exceptional research, education, and patient care--it continues to carry on his vision.
DeBakey's later career was also notable for his work on a radically new type of left ventricular assist device (LVAD.) Cardiac assist devices and total artificial hearts had always been pulsatile, i.e., mimicking the rhythmic pumping action of a natural heart. They were valuable in keeping patients alive while waiting for a transplant, or letting an injured heart recover, but they were also bulky, noisy, and required the patient to be tethered to a power supply and control equipment. They were not completely implantable. In 1984 DeBakey performed a heart transplant on David Saucier, a NASA engineer, and this experience inspired Saucier to develop a smaller, better pump for patients waiting for transplants. By 1988, DeBakey and George Noon were working with him on the device. NASA helped support the initial development of this axial-flow pump, which Saucier and several NASA teams adapted from technology used in space shuttle fuel pumps. In 1996, NASA (which held the patent) granted exclusive technology rights to MicroMed Technology, Inc., so that the device could be further developed into a functional, FDA-approvable treatment for end-stage heart failure. MicroMed CEO Dallas Anderson raised millions of dollars for the effort, and worked closely with DeBakey and Noon to obtain clearance for clinical trials in Europe and the U.S. The European clinical trials began in Berlin in November 1998, and during the following 18 months the MicroMed DeBakey VAD was implanted in more than two dozen patients, all of them on the transplant waiting list. Most were successfully maintained on continuous flow pumps, sometimes for months, before receiving transplants, and were ambulatory and able to exercise while they waited. The miniaturized, battery-operated, continuous-flow pump (3 inches long and weighing less than 4 ounces) can be implanted just below the heart, within a tube bridging the left ventricle and ascending aorta. Its advantages include the small size (making it easier to use on children and smaller patients), lower power requirements, fewer moving parts (no valves or air vents) and much less noise. The DeBakey VAD and similar continuous flow pumps are currently approved for bridge-to-transplant use, and are likely to be used increasingly as permanent "destination" treatments for some types of heart failure. Continuous-flow pumps have also been paired to function as a complete heart in several experimental cases, and show promise for total heart replacement use. In 2001, DeBakey received NASA's Invention of the Year award for the DeBakey Ventricular Assist Device.
During the 1980s, DeBakey, working with Joseph Melnick and others, also investigated how herpes virus, cytomegalovirus, and Chlamydia pneumoniae infections might contribute to the formation of atherosclerotic plaque in the arteries. He scheduled fewer surgeries in his later years (though he continued to operate until he was 90) and devoted more time to compiling and analyzing the more than 60,000 surgical case studies he had generated during his career.