Houston, 5 January 1953
In June 1725 a young man from a town in northern Italy visited the house of a local prostitute, only to be seen a short time afterwards hurrying from the building in an agitated state. What happened next was recorded by the great physician Giovanni Battista Morgagni, who served as professor of anatomy at the University of Padua for over fifty years:
As the woman had not appeared for two or three hours, the neighbours went in and found her dead and cold – lying in bed, in such a posture that it could not be doubted what business she had been engaged in, especially since manly seed could be seen flowing from her female partsfn1.1
Morgagni’s account of this unedifying episode appears in the hugely influential book he published in 1761, The Seats and Causes of Diseases Investigated by Anatomy, a compendium of almost 700 autopsy reports. By comparing his pathological findings with the symptoms the patients had experienced before death, Morgagni hoped to improve the rigour and precision of diagnosis. In this case he was eager to discover the cause of this young woman’s untimely demise, and sent a colleague to inspect the body. In the summer heat there was no time to waste, so the man was instructed to bring back any organs which showed signs of disease. He duly returned with the woman’s internal organs and genitals in a bag, and the following day Morgagni dissected them.
When he examined the heart he soon found something amiss. The organ is normally covered by the pericardium, a tough fibrous sac which holds the heart in place within the chest cavity. As well as protecting the heart from infection, it also contains a small amount of fluid which helps to lubricate it during its pumping movements. This time, however, the pericardial sac was not sitting loosely around the heart as it should, but was distended with dark clotted blood. The major blood vessels displayed no outward abnormality, but when Morgagni cut into the largest, the aorta, he discovered why the young woman had died. Near the point at which the artery leaves the heart he found signs of disease: the wall of the vessel had been weakened and ballooned outwards, a lesion known as an aneurysm. This example was the size of a large walnut. It had ruptured, and huge volumes of blood had been pumped into the pericardium and the chest cavity, causing almost instant death. Morgagni ended his autopsy report with an observation that reads as if it were influenced more by morality than medicine, but which was entirely correct:
When other causes exist, it is not only obvious to reason, but has been demonstrated by dissection, that venereal indulgences greatly tend to accelerate death, by exciting the circulation of blood. They occasion the rupture of latent aneurysms, and the laceration of vessels in the head, which without this or a similar excitation, might have continued to perform their functions much longer—perhaps till old age.2
It is quite plausible that the young woman’s death was a consequence of her profession: aortic aneurysms are now known to be associated with syphilis, and until the advent of penicillin in the 1940s the majority of cases were seen in syphilitic patients. Some were killed suddenly as the aneurysm burst – ‘as instantaneously as if by a pistol-bullet’, in the words of the nineteenth-century physician René Laennec.3 They were the lucky ones: more often the aneurysm would grow, crushing the internal organs, eroding the bones of the spine and ribs and eventually becoming visible through the skin. Patients sometimes died slowly from suffocation, as the aneurysmal sac compressed the windpipe. In 1752 the physician William Hunter was consulted by a corset-maker who had endured the slow growth of his aneurysm for three years, until it protruded through his ribs. Finally it burst as he turned over in bed to cough: ‘The blood gushed out with such violence as to dash against the curtains and wall; and he died, not only without speaking, but without a sigh or groan.’4
Difficult to diagnose and impossible to treat, from the moment they were first identified in the sixteenth century aortic aneurysms became a doctor’s nightmare. A breach in the wall of the aorta is a catastrophe, given the volume and pressure of the blood within, and the fact that it is the only conduit between the heart and major organs. Not only is this 30-centimetre tube vital to life, it is also difficult to reach: the upper part of the aorta is protected by the ribcage, and sits in hazardous proximity to the heart and lungs, while the abdominal aorta is buried deep beneath the viscera, adjacent to the spine. The eighteenth-century medic Henry Mason acknowledged the challenges for the physician: ‘As aneurysms in the internal parts of the body are inaccessible, all that can be done for the patient is, to abate the impetus of the blood’s motion by a thin diet, and repeated bleeding … and the patient at the same time be ordered to refrain from all commotions of body and mind.’5 This was not treatment but palliative care.
The outlook was not much better two hundred years later in 1952, when the American surgeon Michael DeBakey described aortic aneurysm as ‘a fatal disorder, comparable in this respect to cancer’.6 That would soon change. On the last day of that year a forty-six-year-old sheriff from Arkansas was admitted to DeBakey’s Methodist Hospital in Houston. He probably would not have been pleased to be compared with an eighteenth-century Italian prostitute, but from a clinical point of view there was little difference between him and the subject of Morgagni’s autopsy – except that the sheriff was still alive. About three months earlier he had suddenly started to suffer severe back pain, which had spread to his lower abdomen and groin. He was diagnosed with an aortic aneurysm, and his doctors were not surprised to learn that he had previously been treated for syphilis.
By the time he arrived in Houston he was in a bad way, physically and psychologically. Like the soldiers forced to live with shrapnel fragments lodged in their chests, he was anxious that his condition could kill him at any moment. An X-ray revealed a large pulsating mass behind his heart – so large, in fact, that it had displaced his stomach and oesophagus to one side, and had started to erode the bones of his spine.7 The prognosis was dire: no patient had ever survived an aneurysm of this size. And yet three weeks later he would leave Methodist Hospital in excellent health, and be back at work within a couple of months. The operation that cured him was the first in a series of brilliant interventions which both made DeBakey’s reputation and prepared the ground for a decade of rapid progress in cardiac surgery. It was also the greatest achievement to date of a medical discipline which had been practised for almost two thousand years – vascular surgery, the surgery of the blood vessels.
Ancient doctors frequently wrote about the blood vessels, although their work was founded on the misconception that the veins and arteries also transported pneuma, a vital spirit derived from inhaled air. Nevertheless, a Greek surgeon of the second century AD not only described aneurysms but devised an operation so sophisticated that it enjoyed an unlikely renaissance almost 1,800 years later. Very little is known about Antyllus, whom the great Canadian physician and historian of medicine Sir William Osler described as ‘one of the most daring and accomplished surgeons of all time’.8 In his treatise On Medicine, Antyllus distinguished between traumatic aneurysms and those caused by disease, and offered advice on which were amenable to surgery. He ruled out aneurysms occurring in arteries of the neck, armpit and groin as too dangerous to treat, owing to the large size of the vessels involved, but described a procedure which could be used elsewhere in the body. This entailed making an incision in the skin above the artery, dissecting the vessel clear of its surrounding tissue, and using threads to tie it closed on either side of the aneurysm. Finally the aneurysm was slit open to evacuate the blood and any clot trapped inside it, and the empty sac was packed with wadding.9 This left a section of blood vessel permanently out of commission, but the body would soon compensate for the deficiency; besides, it was better than letting the aneurysm burst. An alternative method was suggested by Antyllus’ near-contemporary Galen, who recommended compressing the aneurysm from outside the skin until it disappeared.10
These were important contributions, but such methods were only applicable to aneurysms of the smaller arteries which lay near the surface of the body. It was not even known that the aorta was also prone to aneurysm until 1552, when the French physician Jean Fernel observed during post-mortem dissections that they could occur inside the chest. The greatest anatomist of the Renaissance, his contemporary Andreas Vesalius, also described them and is believed to have been the first to diagnose an aortic aneurysm while the patient was still alive.11
Treatment was another matter. Ambroise Paré, surgeon to the French king Henry II, described the characteristic sound of blood flowing through an aneurysm as ‘a sensible hissing, if you lay your ear next to them’. This noise, known today as a ‘bruit’, is caused by turbulent flow inside the aneurysmal sac. Where suitable, Paré recommended the operation of Antyllus. But he also asserted that aneurysms deep inside the body were incurable, citing the story of a tailor ‘who by an aneurysm of the arterious vein [aorta] suddenly whilst he was playing at tennis fell down dead, the vessel being broken’.12 Noting that those who suffered such deaths often turned out to have a history of venereal disease, he recommended a diet of ‘curds and new cheeses’, and taking an infusion of barley water and poppy seeds.
No real progress with treatment was made until the eighteenth century, when the Scottish brothers William and John Hunter turned their attention to the subject. William, the elder of the two, was a physician and anatomist who, in a detailed study of aneurysms which drew heavily on his experience of dissecting cadavers, described the dramatic death of the corset-maker we read earlier. His brother John started his career as William’s assistant in his school of anatomy in Soho, and probably became interested in the possibilities of surgical aneurysm repair as a result.13 William was a figure of great eminence, respected as a teacher and as the leading obstetrician of his generation, but his reputation would soon be eclipsed by that of his younger brother.
John Hunter was not only a talented clinician but also an important experimental scientist who performed pioneering research into transplantation and the placebo effect. His deep interest in the structures of the body and their functions led him to study how anatomy differed between humans and other animals, and over many years he amassed a huge collection of more than 15,000 specimens drawn from several hundred animal and plant species. After his death it was purchased by the British government, and although a large number of items were destroyed in an air raid in 1941 it still forms the core of the Hunterian Museum of the Royal College of Surgeons in London, one of the world’s greatest anatomical collections.
Among the museum’s artefacts is a memento of one of the achievements that made John Hunter the most celebrated surgeon of his era: a preparation of a blood vessel taken from a human leg following an operation he developed in the 1780s to treat aneurysms. Hunter had frequently performed Antyllus’ procedure, but grew frustrated with its failure in aneurysms of the popliteal artery, a blood vessel located deep in the tissue of the thigh. Many surgeons preferred to amputate the leg, which Hunter thought a grotesque admission of failure, and after conducting experiments on dogs he devised an alternative. The first attempt on a human patient was made in December 1785, when he treated a coachman aged forty-five with a longstanding popliteal aneurysm.fn2 His leg was swollen and had turned an unhealthy mottled brown, but despite his discomfort he begged Hunter not to deprive him of his livelihood by amputating.
Hunter began by making an incision along the coachman’s inner thigh, and then dissected the artery free. He realised that the conventional method of tying the artery closed just above the aneurysm was doomed to failure, since this section was also likely to be diseased and the ligatures would eventually cut through it, causing major haemorrhage. Instead he attached four cotton ligatures around the artery some distance above the aneurysmal sac, where the vessel was still healthy.fn3 The rationale behind this procedure was simple: if the blood supply to the aneurysm were cut off it would no longer increase in size, the contents of the sac would clot and in time be reabsorbed by the body. After a long convalescence complicated by bleeding and infection the patient was eventually much improved, and by July had returned to his work driving a hackney carriage.14 Hunter’s next three patients fared even better, and five years after the operation were all living normal lives.15
The Hunterian operation for aneurysm quickly became the standard procedure for the condition. Hunter’s pupil Sir Astley Cooper, the outstanding surgeon of the next generation, called it ‘one of the greatest triumphs of our science’.16 And in 1817 Cooper in turn became the first surgeon to apply a ligature to the aorta, using Hunter’s method. His patient was Charles Hutson, a thirty-eight-year-old porter who had been admitted to Guy’s Hospital with a swollen groin. Cooper could feel a pulsation in the swelling, a sure sign that it was a grossly distended artery rather than a tumour. He realised that the affected vessel was deep inside the abdomen, making any surgical intervention hugely risky. For several weeks he tried more conservative treatments, including bloodletting and the application of pressure to the swelling. But when the aneurysm began to bleed through the skin he had no alternative but to operate.
Cooper began by administering a dose of opium to his patient – the only pain relief he would receive during this highly invasive procedure – before making an incision in the man’s abdomen. That must have been painful enough, but judging by the surgeon’s own account of the operation the sequel was truly excruciating: ‘Having made a sufficient opening to admit my finger into the abdomen, I then passed it between the intestines to the spine, and felt the aorta greatly enlarged, and beating with excessive force.’17 After using his fingernail to make space behind it, he then managed to pass a ligature around the vessel to tie it closed. The ends of the ligature were passed between the intestines and left hanging out of the wound to enable further tightening if required. The patient died a few days later, but Cooper had proved that the undertaking was possible, and his daring feat was immediately feted as a landmark in surgery: the patient’s aorta, and the ligature Cooper tied around it, can still be seen in the Gordon Museum of Pathology at King’s College London.
Few dared to repeat the operation, and though hundreds of articles were written about aortic aneurysm there was no further breakthrough until much later in the nineteenth century, when doctors noticed that some patients improved after the symptoms first appeared. The explanation, they realised, was that blood clots were forming inside the aneurysm, reducing the pressure on its walls. The Scottish physician Alexander Monro, writing in 1827, described one such patient who survived for some time with an aortic aneurysm ‘as large as a child’s head’.18 He recommended treating aneurysms by the use of measures intended to promote coagulation inside the sac, such as bloodletting, bed rest, and a simple diet.
Clotting was known as ‘Nature’s cure’ for an aneurysm, and for decades most specialists preferred to take this conservative approach, until the Victorian surgeon Charles Moore pioneered an ingenious operation that was still in use in the 1940s. On 20 February 1863 he was asked to examine a patient with a large aortic aneurysm which had started to protrude through the ribs. Moore knew that surgery was not yet equal to the task of treating the artery itself, and it occurred to him that one alternative might be to harness the body’s natural defence mechanisms. Foreign objects in the bloodstream tend to provoke clotting, since they are quickly surrounded and encapsulated by cells called platelets as the body tries to isolate any potential threat. Moore believed that if he could introduce a suitable object into the aneurysm, any blood in contact with it would quickly coagulate. The larger the surface area of this object, he realised, the more blood would clot, and a suitable substance immediately suggested itself: ‘If a large quantity of wire could be introduced into the interior of an aneurysm, and disposed about it in coils, a corresponding quantity of fibrin [a fibrous protein involved in clotting] would soon accumulate and increase upon it.’19
To Moore’s disappointment, his patient – perhaps disturbed at the prospect of being a guinea pig – discharged himself from the hospital, so it was almost a year before he had the opportunity to put his theory into practice. On 7 January 1864 he operated on Daniel D., a twenty-seven-year-old with a gigantic aneurysm which protruded almost three inches from his chest. No incision or anaesthetic were necessary: Moore simply inserted a small tube into the aneurysm and through it threaded an astonishing 26 yards of fine steel wire, which formed coils inside the aneurysmal sac. The patient lived for only four more days: the operation had been too late to save him. An autopsy revealed, however, that the aneurysm was already filled with ‘a fibrinous coagulum, enveloping and imbedded in the coils of wire’,20 showing that Moore’s theory was sound.
Other surgeons quickly grasped the elegant simplicity of the procedure and continued to use it with a number of modifications. Catgut, silk and horsehair were tried instead of wire,21 and two Italian surgeons even inserted a large number of watch springs into an aneurysm, an experiment which ended fatally when some of them entered the heart.22 Copper and silver wire were also used, as much as 200 feet of it, and from the 1870s onwards electric current was sometimes applied to the coils in order to heat them and increase the speed of clotting. In the mid-1930s the American Arthur Blakemore adapted this technique, using a fine wire made of a copper–silver alloy and insulated with enamel. By carefully controlling the current passing through the wire he could heat the coils to 80°C, the optimum temperature for coagulation.23 His initial results were encouraging – six of eleven patients experienced an improvement in their condition – but after later disappointments his method failed to gain widespread acceptance.
Alternatives were proposed: surgeons tried injecting gelatine and other liquids into the sac to promote coagulation,24 and others applied ligatures to the arteries coming off the aortic arch in order to slow the flow of blood through the aneurysm. A wide variety of bizarre materials was employed for this operation, including kangaroo tendons25 and ox aorta,26 as surgeons tried to find a substance tougher than cotton but sufficiently similar to the body’s own tissue that it would not provoke inflammation. One surgeon even wrote to the British Medical Journal in 1887 to recommend bloodletting,27 a treatment which was archaic even then. Such therapies smacked of desperation; a new approach was needed.
Curiously it was a return to ancient medicine, and the method of Antyllus, that revealed the way forward. In January 1888 a young American called Manuel Harris was accidentally shot while hunting rabbits, and two months later was admitted to Charity Hospital in New Orleans with a swollen upper left arm. He was treated by Rudolph Matas, a twenty-seven-year-old surgeon who with his neat goatee and steel-rimmed spectacles had the air and gravitas of a Viennese intellectual. The son of Spanish immigrants, Matas had grown up on a Louisiana plantation and became a considerable scholar, with such a passion for knowledge that the foundations of his house had to be reinforced to prevent the building sinking under the weight of his library.28 Matas examined his patient and discovered that lead shot had caused a large aneurysm of the brachial artery, the major blood vessel of the upper arm.
Having failed to check the growth of the aneurysm using compression, Matas applied a ligature to the artery, but this too was unsuccessful. With amputation the only alternative, he operated again. After placing a second ligature below the aneurysm, he cut into the sac and removed the clot inside it. He could now see that blood was continuing to seep into the sac despite the ligatures, so he sealed both ends with silk thread before sewing up the external wound. His patient made a complete recovery, but in his report of the case Matas claimed little credit: he pointed out that he had merely been following the example of Antyllus, and that the advent of anaesthesia, ‘which allows the operator to cut with a calm and deliberation that were denied his ancestors’, had made the operation respectable once more.29
Despite its success, Matas did not dare to repeat the procedure for almost fifteen years. But after several similar cases came his way he made an intense study of the problem, and in 1902 described his technique to colleagues.30 He gave it the name ‘endo-aneurysmorrhaphy’, an inelegant term for one of the great breakthroughs in vascular medicine. The essence of Matas’s operation was that the aneurysm was cut open and the lower edges of the sac folded and sutured together to restore the artery’s normal diameter. To visualise the procedure, imagine that a thrifty vascular surgeon buys a cheap garden hose which turns out to have a weak spot in its tubing. Water pressure soon causes the plastic at this weak point to balloon outwards, forming an ‘aneurysm’. If this should burst the hose would be ruined, so the vascular surgeon decides to repair it by performing endo-aneurysmorrhaphy. After turning the water off he makes a slit along the bulging section and then sews the sides together so that the tubing is of uniform diameter once more.
Matas had shown that surgeons need not rely on palliative measures to treat aneurysms. But although endo-aneurysmorrhaphy was adopted as the standard technique for treating the peripheral blood vessels it was still too dangerous to use it on the aorta, where the blood flow could not be interrupted for any length of time. He did, however, have one notable but solitary success in treating the condition. In 1923, in an operation reminiscent of Sir Astley Cooper’s a century earlier, Matas treated a young woman severely debilitated by syphilis. She had a large aneurysm of the abdominal aorta, which had started to leak. Because it was near the lower end of the vessel, below the kidneys, Matas decided it was safe to intervene. He wrapped two cotton tapes tightly around the aorta, immediately above the aneurysm, so as to prevent any blood flowing through it. This was a radical intervention which shut off much of the circulation to the woman’s legs, but Matas was relieved to find that sufficient blood was finding its way to them through other smaller vessels. The aneurysm shrank dramatically, and she lived for over a year before she died from an unrelated bout of tuberculosis.31
This method of ligating the aorta was employed by other surgeons, but with mixed results. Until the 1950s there remained no entirely satisfactory treatment for aortic aneurysm, although several new techniques were tested. There was even a brief vogue for wrapping them in cellophane, which appeared to slow their growth. In December 1948 Albert Einstein became the most famous patient to undergo this procedure for a large aneurysm of the abdominal aorta. He did remarkably well, and was able to return to work within a matter of weeks. He remained in good health for another six years; by the time his original symptoms returned in April 1955, surgery had evolved to the point that it might have cured him entirely. His doctors recommended a second operation, but at the age of seventy-six Einstein had had enough, telling the surgeon John Glenn: ‘I want to go when I want. It is tasteless to prolong life artificially. I have done my share, it is time to go. I will do it elegantly.’32 He died peacefully in Princeton University Hospital a few days later.
Indirect approaches to aneurysms had not worked; what surgeons yearned to do was cut them out – a daunting prospect, attended with Formidable risks; but slowly, over several decades, all the major obstacles were overcome. The first step on this long path was taken at the beginning of the twentieth century by the Frenchman Théodore Tuffier, an enterprising surgeon who was a pioneer in many fields. In 1901 he was asked to look at a forty-year-old woman who had arrived at the Hôtel-Dieu hospital in Paris complaining of chest pain. A pulsating tumour the size of a pigeon’s egg had recently appeared between two of her ribs: an X-ray showed that this was merely a small portion of an aneurysm of the aortic arch the size of a large fist. Tuffier believed that only an operation could save her, and explained to the woman and her family that nothing of the kind had ever been attempted before. Having obtained their consent, on 12 December he operated.
When he opened her chest, Tuffier discovered that the aneurysm had already eaten into her ribs, its walls were dangerously thin and it was close to bursting. But there were more encouraging signs: the aperture connecting this large sac of blood to the aorta was small, and Tuffier thought it should be possible simply to tie it closed. Carefully watching the patient’s pulse and breathing, he attached a catgut ligature around the neck of the aneurysmal sac, which immediately deflated as its blood supply was removed. Thrilled at this sign of success, Tuffier thought it safe to terminate the operation. But he had made a critical error. Rather than cut the aneurysm out entirely he left the empty sac in situ, assuming that it would contain any subsequent bleeding, an insurance policy against future mishap. Alas, this was a fatal miscalculation: two weeks later the woman died after the tissue he had left behind became gangrenous.33
For the next four decades surgeons largely avoided such direct approaches to aneurysms, dissuaded by the unsuccessful outcome of Tuffier’s operation. Instead they preferred methods such as wiring them or placing a ligature across the aorta. The results were so dismal that in 1940 an American expert, Ivan Bigger, was forced to admit that ‘up to the present time, all forms of therapy have yielded poor results’.34 But rapid progress in the treatment of congenital heart conditions in the 1940s would prove to be of crucial importance. Until Clarence Crafoord’s successful treatment of aortic coarctation in 1944, most specialists believed that interrupting the flow of blood through the upper part of the aorta would have rapidly fatal consequences. Knowing that this was not the case gave them new confidence in their ability to attack the vessel directly.
In 1947, Harris Shumacker, a surgeon at Yale, was operating on an eight-year-old boy who had been diagnosed with coarctation. When he opened the patient’s chest and laboriously dissected away the tissues around the heart he could see the characteristic narrowing of the aorta, but just below it – and unexpectedly – there was a large aneurysm. With nothing to be gained from abandoning the operation, he clamped the aorta above and below the area of constriction and cut out a 3-centimetre section of the vessel, together with the aneurysmal sac. He then sutured together the two ends of the aorta and slowly removed the clamps to restore blood flow through the repaired vessel. His patient made a good recovery. This was an unplanned aneurysm repair, but thanks to Shumacker’s presence of mind and willingness to improvise, it worked.35
Shumacker had trained under the Blue Baby pioneer Alfred Blalock, and it was no coincidence that another surgeon who made an early aneurysm repair was also a Blalock protégé. Denton Cooley, who had been present as a young student at the first Blue Baby operation in 1944, had a particularly dramatic first experience. In 1949 he was assisting a senior colleague, Grant Ward, in an operation on a patient who had previously been treated for cancer of the breastbone. During an earlier operation the cancerous bone had been replaced with a metal plate, but this had caused complications. When they removed it to investigate, a jet of blood spurted from the man’s chest with such force that it hit the ceiling. Dr Ward quickly thrust his left hand into the chest cavity and stemmed the flow with his fingers. But this was the end of his involvement in proceedings: his right arm was paralysed as the result of a spinal disease and hung uselessly from a splint. After a moment of panic he regained his sangfroid, crisply asking Cooley to help him get his finger ‘out of this hole’.36
Blood at such pressure could only come from the aorta, and when Cooley peered into the open thorax he saw a large aneurysm which had already burst. This horrifying scenario was far beyond his knowledge or experience so he improvised, using a portion of chest muscle to patch the breach.37 After several nerve-wracking minutes the fountain of blood had been staunched, and Ward could remove his finger. But this was only a temporary solution: the repair would not hold for long. The two surgeons looked at each other and wondered what to do next. Cooley suggested putting a clamp on the aorta to stop the flow of blood temporarily, giving them a few minutes to sew up the hole. With no viable alternative they decided to go ahead; their patient stabilised and a few hours later was back on the ward. Cooley would go on to repair several other aneurysms at Johns Hopkins using this simple method of clamping the aorta while the aneurysmal sac was excised and the hole in the aorta repaired. The technique was dubbed ‘clamp and sew’, and was the first successful means of removing aneurysms. And these formative early experiences, operating at the limits of what was known to be possible, were to prove invaluable when he left Baltimore in 1951 to start a new job in Houston.
Today Methodist Hospital is at the heart of the Texas Medical Center, a vast campus of twenty-one hospitals covering more than a square mile. But in 1948, when Michael DeBakey was appointed head of its surgical department, Houston was still a medical backwater. He arrived as the only surgeon in the city with advanced qualifications, and was horrified to discover inexperienced general practitioners attempting complex operations, with predictably awful results. Over the next few years he transformed the department, ejecting incompetent doctors and hiring the most talented young surgeons he could find. Denton Cooley was a great catch: after training with Albert Blalock he had worked with Russell Brock in London, and already had an enviable reputation as a quick and technically brilliant operator.
Cooley’s arrival in Houston brought together two of the greatest surgeons of the twentieth century. But they were very different characters. Cooley had been something of a jock at the University of Texas, where he had excelled at basketball and was a prominent fraternity member. At thirty-one he still bore a permanent reminder of these rowdy student days: the initials UT, branded into his chest with a red-hot iron during an initiation ceremony.38 The affable, laid-back Texan could not have been a greater contrast to DeBakey, a ferociously intense Southerner of Lebanese descent who rose by 4 a.m. and rarely took a day off. A 1965 profile in Time magazine called him ‘the Texas Tornado’,39 capturing something drastically elemental about him. On his morning rounds he would tear through the hospital, with juniors and students trailing in his wake as he bounded up the stairs between floors. With patients he was gentle and attentive, but subordinates who allowed their concentration to waver for a second could expect a volley of abuse, or banishment from the operating room; on more than one occasion a trainee ejected from theatre for some misdemeanour promptly left the hospital, never to return. Perhaps it was inevitable that these two powerful characters would eventually fall out – and catastrophically – but for over a decade they collaborated on some of the most important work ever done in an operating theatre.
On 11 June 1951, Cooley’s first day in his new job, he accompanied DeBakey on his morning rounds. One of the patients, a forty-six-year-old man, had an aneurysm so large that it threatened to break through the skin of his chest. DeBakey asked his new recruit what he thought ought to be done. To his surprise, Cooley replied that he had previous experience of the condition, and that he believed that he could put a clamp across the aorta, remove the aneurysm and repair the blood vessel. Impressed, DeBakey invited him to make an attempt, and when he entered the operating theatre the following day he found that his junior had already succeeded in removing the lesion and was in the process of repairing the aorta. The patient went on to make a full recovery.40
In his memoirs Cooley suggests that this operation in June 1951 was the first successful aneurysm repair of its type anywhere in the world. Surgeons, as we have seen, can become obsessed with priority, and this is an interesting example of their determination to come first: DeBakey liked to point out that he had himself performed a similar procedure three years earlier,41 while his mentor Alton Ochsner reported a successful operation in New Orleans as early as 1944.42 Such conflicting claims are not uncommon; complicating matters still further, the chief surgeon at a hospital was for many years entitled to put his name to any journal article emanating from his department, whether or not he had personally conducted the operation it reported. This often led to situations where two surgeons at the same hospital took credit for a ‘first’, with callous disregard for the convenience of medical historians.
Such disputes had not yet tarnished the relationship of DeBakey and Cooley in 1952, when they collaborated on a study of previous attempts to treat aortic aneurysm, including their own. They observed that most surgeons had been ‘concerned with palliative rather than curative therapy and the results therefore have been somewhat disappointing’43 – an understated way of saying that surgery had so far completely failed to find a reliable method of curing this deadly condition. They vowed to adopt a more aggressive approach, one in which the ideal outcome was the total removal of the aneurysmal sac; in other words, a comprehensive cure.
This was the mindset of the two surgeons when the sheriff from Arkansas arrived on New Year’s Eve, 1952. Having already established that he had a large aneurysm, they investigated further by taking an aortogram three days later. During this procedure dye is injected into the aorta while an X-ray is taken, allowing doctors to see the outlines of the blood vessels. This showed an extensive aneurysm with a layer of clot on both sides, which had pushed the aorta out of its usual position. But it also revealed a more formidable problem.
Aneurysms come in two main types: sacciform and fusiform. In sacciform aneurysms, a bladder-like swelling arises from a single weak spot in the vessel wall. These were the first to be successfully treated, since if the neck of the sac was sufficiently narrow surgeons could simply clamp it shut and remove the sac. The second kind was far more challenging. ‘Fusiform’ means ‘spindle-shaped’, and aneurysms of this variety affect the artery’s entire circumference, so that the sac is not a bag attached to the aorta but forms part of the vessel itself. This was what the surgeons saw on the aortogram: removing it would be extremely challenging, since it would entail cutting out a lengthy section of the aorta. Shumacker had managed to remove an aneurysm by excising a few centimetres of the vessel and stitching the ends together, but the example they were now looking at was fully 20 centimetres long. Cutting it out would leave a gaping void where a blood vessel should be; they would have to find a way to bridge this gap.
On 5 January the sheriff was put to sleep with ether and placed on his right side. DeBakey made an incision in his chest and lifted up one of the lungs, revealing the aneurysm. A 20-centimetre section of the aorta had ballooned into a swelling 20 centimetres in diameter, like the distended belly of a snake that has gorged itself. The aneurysm had adhered to the bones of the spine and was awkwardly situated near the point at which the aorta passes through the diaphragm, the tough sheet of muscle separating the thorax from the abdomen. In order to approach the sac, DeBakey had to remove the patient’s spleen and then cut through the diaphragm. He injected heparin, an anticoagulant, into the aorta and then placed clamps on the vessel above and below the aneurysm. Next came the job of separating the sac from the tissues around it, without damaging any of the delicate structures to which it had attached itself.
While he applied himself to this task, one of his assistants was examining the contents of a small glass jar: a section of aorta taken from the body of a twenty-one-year-old man who had died in a car crash six days earlier. Shortly after his death it had been excised, placed in a salt solution containing a large amount of antibiotics to prevent infection, and refrigerated. Once the diseased section of the sheriff’s aorta had been removed, a graft of this tissue would replace it. The assistant trimmed it to the required length and handed it to DeBakey, who had by now cut out a substantial portion of the aorta, including part of the aneurysm.
The graft was placed in the gap between the two cut ends of the aorta, and working quickly but meticulously DeBakey sutured the graft into position. By the time he had finished, the clamps had been on the aorta for three-quarters of an hour. Gradually, so as not to cause any shock to the patient’s system, these were now released, allowing blood to flow through his new aorta for the first time. DeBakey and his colleagues watched carefully for any signs of leakage: despite the high pressure within the vessel, the join was so good that only a few drops of blood oozed through the suture holes. With the circulation restored, they could now remove the rest of the aneurysm and its contents. It was so huge that it left a large cavity in the abdomen, leading DeBakey to worry that the sharp cartilages between the vertebrae, which protruded into this space, might puncture the new graft. So he took the precaution of suturing around the graft a section of omentum, a fatty membrane which normally covers the abdominal contents, to act as a protective bandage.
By the time he had repaired the diaphragm, replaced the rib and closed his original incision, DeBakey had been operating for four and a half hours. The patient was stable, and although his lung partially collapsed the following day, this was quickly treated and he was able to get out of bed six days later. He was transformed: the pain had disappeared and his circulation had dramatically improved. A mere fortnight after undergoing this major operation he was able to go home, and was back at work a month later.44
That was not the last that Michael DeBakey saw of the sheriff, however. In August 1962 he returned to Methodist Hospital with lung cancer. An aortogram revealed that the grafted blood vessel was still functioning normally: the operation had been a complete success. DeBakey had given him an extra decade of life, but this time he could do little to help him; he removed the cancerous lung, but the sheriff succumbed to his illness a few months later.45
As it turned out, he was lucky to survive so long. Arterial grafts from cadavers – known as homografts – had first been used in 1945 by Robert Gross to repair coarctation, and then to replace an aortic aneurysm by another American surgeon, Henry Swan, in 1949.46 But problems soon emerged: they had a tendency to deteriorate once implanted, and several patients died after they began to leak. Homografts could only be stored for a couple of weeks, and obtaining them in the first place was difficult. DeBakey and his team were fortunate to have a ready supply of grafts taken from autopsies conducted at another local hospital, having come to an agreement with the state medical examiner47 – but they were obtained without family consent, an arrangement that would now be deemed highly unethical. Some attempts were made to set up regional artery banks, along the same lines as blood banks, but these efforts foundered when surgeons came to understand that they needed something more durable than tissue from cadavers. DeBakey even experimented with blood vessels taken from other species including horses and giraffes,48 which have notably tough aortas, but these tissues were rejected by human bodies. He and others had taken great strides forward, but what surgeons really needed was an artificial blood vessel which could be manufactured to order.
In 1901 a young Frenchman, Alexis Carrel, visited Messieurs Assada, a wholesale supplier of sewing equipment in Lyon. He was trying to get hold of some unusually fine needles and thread, and lacemaking equipment turned out to be precisely what he needed. Carrel was already skilled in embroidery, having taken lessons with a local seamstress, Mme Leroudier49 – but his interest was not in repairing clothes, but human tissue. For the first time (but not the last), haberdashery was to play an unexpectedly important role in the story of vascular surgery.
It was a dramatic political assassination that set Carrel on this path. In June 1894 he was a medical student at the University of Lyon when the French president Marie Sadi Carnot made a visit to the city. As the president left the Palais de Commerce a young Italian anarchist approached his carriage and stabbed him with a dagger. The blade severed one of his portal veins, a major blood vessel supplying the liver, and although he was taken straight to hospital the injury proved fatal. Doctors realised there was nothing they could do for him and watched helplessly as he died slowly from massive blood loss. Lyon erupted in fury, and mobs avenged the president’s death by wrecking every Italian café and bar in the city. Carrel was also outraged by the murder, but his reaction was more constructive: realising that the current state of surgical knowledge was inadequate for dealing with such serious injuries, he resolved to do something about it.50
At the time of Sadi Carnot’s assassination nobody had yet succeeded in repairing a completely severed blood vessel. One of Carrel’s professors, Mathieu Jaboulay, was interested in the problem, and in 1895 conducted successful experiments with donkeys and dogs, cutting their carotid arteries and then reuniting the ends by suture.51 Carrel soon improved his teacher’s technique, using tiny needles and fine silk thread coated with Vaseline, which sealed the holes created by each stitch. He then discovered a neat method to join the cut ends of a blood vessel, which he called ‘triangulation’: the vessel was first united with three stitches, at equal distances around its circumference. An assistant proceeded to pull these threads, stretching the circular cross-section of the blood vessel into a triangle. Sutures could then be placed on the three sides of this triangle, a much easier procedure than attempting to stitch around a circular surface; when the pressure on the three threads was relaxed, the blood vessel returned to its normal shape, with both ends perfectly united.52 This remains one of the standard techniques of vascular surgery today.
Carrel began this work as a student in Lyon but completed it in America, where he emigrated in 1903. Briefly disillusioned with medicine, his original plan was to become a rancher in Canada, but thankfully he was dissuaded from this course of action and instead found work in a Chicago medical laboratory before moving to the Rockefeller Institute in New York. The lavish resources of the Institute were put at his disposal, and Carrel was able to set up a state-of-the-art research facility. An English visitor recorded his impressions of this unusual place in an article published in 1926:
Carrel’s operative theatre is all black; so are the gowns of his assistants and himself. In fact, all is black, with the exception of his operation area. He can get his fine needles made only in England. It takes a month of effort before his theatre sister can thread these needles; the filament of silk is pushed through the eye of the needle obliquely along the shank. The operating theatre for animals is as perfectly equipped as any I’ve seen for human beings.53
In his early experiments on animals Carrel perfected his method of suturing blood vessels, work which would later win him a Nobel Prize. But he soon became aware that there were circumstances in which arteries or veins could not simply be stitched together; it was sometimes desirable to replace an entire section of vessel. His teacher Jaboulay had attempted to transplant a length of artery as early as 1896, but his suture technique was primitive and the operation failed. In 1905, using his more sophisticated method, Carrel cut out part of the aorta of a dog and replaced it with a section of vessel taken from another animal; nine months later it was still alive.
This was an important breakthrough, but Carrel realised that opportunities to perform this operation on humans would be rare, since fresh arteries were difficult to obtain. He proposed two alternatives. Firstly, veins could be used to replace sections of artery: the network of veins in the body provides many possible paths for blood to travel from the extremities back to the heart, so removing a short section of vein from the leg (for instance) causes no long-term problems. This suggestion was prophetic, since the technique is regularly employed today in coronary artery bypass operations. His second proposal was that sections of artery could be removed from cadavers and preserved for future use. In February 1907 he took a section of carotid artery from a dog which had just been killed, placed it in a preserving solution and refrigerated it. Ten days later the blood vessel was transplanted into a second dog. In May 1908, more than a year after the initial operation, Carrel inspected the artery and found that it was still functioning perfectly; in his idiosyncratic English, Carrel observed that ‘a vessel transplanted after having been kept in cold storage for a few days or weeks can functionate normally for a long time’.54
It was these animal experiments by Carrel that laid the foundations for the use of homografts in aortic repair four decades later; in 1910 he predicted as much, writing that ‘it is probable that the aneurysms of the thoracic aorta could be extirpated and the circulation re-established by a vascular transplantation’.55 But this was only one strand of his research. While still working in France, Carrel experimented with small tubes made of magnesium and even caramel as replacements for sections of artery. Both substances were chosen because they would dissolve over time: Carrel conjectured that by the time the tubes had melted away the body would have laid down new tissue inside them, essentially manufacturing its own new blood vessel.56 This was little more than an inspired guess, which would eventually be proved correct. Unfortunately Carrel found that they soon became blocked by blood clots, so he tested other materials, using tubes made of glass and rubber coated with Vaseline. These were better, but clots remained a common complication.57
Although glass and metal tubes were sometimes used in the treatment of arterial injury during the Second World War, these problems persisted. It was not until 1947 that a better alternative was found. A young American research scientist, Arthur Voorhees, was trying to develop an artificial heart valve, implanting his prototypes in canine hearts. One day he noticed that he had mistakenly placed a silk suture so that it passed into one of the chambers of the heart rather than through the cardiac muscle. Several months later, at autopsy, he discovered that the silk had become covered in what appeared to be normal heart tissue. This made him consider whether the body might lay down tissue over a piece of cloth; if the cloth were fashioned into a cylinder, he speculated that its inner surface might function as a lattice for the formation of a new blood vessel. Putting this theory to the test, he sewed a silk handkerchief into a tube and used it to replace a section of a dog’s aorta. Blood passed through the makeshift artery for an hour but then began to leak through the loose weave of the silk, and the dog died.58
Still convinced that his idea had merit, Voorhees kept searching for more suitable material. The following year he was working in a military medical facility in Texas, and happened to be given a sample of vinyon-N, a tough polymer fabric used to make parachutes. Working with a senior colleague, Arthur Blakemore, Voorhees conducted a series of experiments in which vinyon-N grafts up to 6 centimetres long were implanted into the abdominal aortas of dogs, and in 1952 was able to report a promising trial involving fifteen animals. It was not an unqualified success, however: several developed clots inside the prosthesis, a difficulty which needed to be overcome before the technique could be attempted on humans.59 Nevertheless, when his research was published it provoked great interest, and researchers across America were inspired to begin to work on the problem. Voorhees had arrived at an important insight: if the weave of the material chosen for a prosthetic blood vessel was of the right size, fibrin would quickly plug the holes between its threads. Eventually these fibrin plugs would be replaced by fibroblasts, the cells that synthesise connective tissue, and a new endothelium – the inner layer of blood vessels – would be formed. In effect, the fabric functioned as a scaffold on which the body could construct a new artery.
In their attempts to find the perfect material, researchers in the early 1950s fashioned prototype blood vessels from a variety of different synthetic cloths: Orlon, Teflon and nylon were all tried. Michael DeBakey took a close interest in these developments, and one day in 1952 he visited a haberdasher’s in Houston to buy some nylon for his own experiments. To his annoyance it was out of stock, but the assistant who served him suggested he try another new material: Dacron. Patented by two British chemists in 1941, and sold in the UK under the brand name Terylene, this was the first polyester fabric. It turned out to be exactly what he was looking for.
DeBakey needed no assistance in making the first Dacron grafts: his mother had taught him to sew as a little boy, and by the age of ten he was making his own shirts.60 Having borrowed his wife’s sewing machine, he cut out rectangles of the material and sewed together the longer edges to make a cylinder. After successful tests on animals, he implanted the first of these home-made arterial prostheses in a human on 2 September 1954. The patient had a large aneurysm of the abdominal aorta, at the point where the vessel splits into two; DeBakey had manufactured a Y-shaped Dacron graft which replicated this bifurcation, and used it to replace the lower section of the aorta and the top part of both the smaller vessels below. The patient survived for another ten years after the operation.61
The adoption of Dacron was a major advance. None of the other materials tested could match it: Orlon grafts became misshapen after a few months, while nylon had an unfortunate tendency to break down inside the body.62 It transpired that Teflon arteries, like Teflon-lined saucepans, were non-stick: their inner surfaces were so smooth that they significantly inhibited atherosclerosis, the deposit of fatty plaques inside the vessel.63 Unfortunately this otherwise desirable property also prevented new tissue from growing inside the graft. Dacron suffered from none of these drawbacks: a new lining of endothelial cells quickly appeared on the porous inner surface of the cloth, so that the blood was not harmed by contact with synthetic material. But the first Dacron grafts were not wholly satisfactory: because they were made by hand, they had a seam running down one side where the two sides of the fabric had been sewn together, a potential weakness. Approximately 6 litres of blood passes through the aorta every minute, so the graft needed to be as strong as possible in order to contain this high-pressure flow.
One of the earliest patients to receive one was Arthur Hanisch, who travelled from his home in California to be treated for a large aneurysm of the abdominal aorta. Hanisch was a wealthy man, the president of one of America’s largest pharmaceutical companies, and after being cured he expected to receive a bill for at least $10,000. But he had not reckoned with DeBakey’s quirky charging policy. The surgeon routinely refused payment from teachers and other doctors,64 and for rich patients sometimes waived his fees, suggesting instead that they make a donation towards the hospital’s research projects. This strategy regularly paid dividends, and Hanisch’s reaction was typical: astonished by the gesture, he wrote cheques over the next few years for several hundred thousand dollars, many times what he would have paid for his treatment.
Hanisch’s support was not purely financial. When DeBakey explained how he needed to improve his fabric grafts, the pharmaceutical magnate revealed that he was also the major shareholder in a sock factory in Pennsylvania. Through this connection DeBakey met Tom Edman, a young textiles researcher who designed a new type of knitting machine, paid for by Hanisch.65 It produced a continuous tube of Dacron, seamless like a sock, which could be fashioned into grafts of various sizes. These could even be customised to fit the patient’s needs: if an aneurysm affected the junction of the aorta and the renal arteries (the vessels supplying the kidneys), a Dacron prosthesis could be manufactured with branches to match the patient’s anatomy.
A committee of the American Medical Association had been set up to study the relative merits of different types of fabric graft, and a major study in 1955 concluded that Dacron was the best available.66 From 1957 DeBakey, Cooley and their colleagues used it exclusively, and by the following year they had treated 737 patients, reporting their results as ‘most satisfactory’.67 Further improvements were to come: Cooley discovered that if the grafts were steeped in the patient’s own blood before implantation and then heated in an autoclave, the blood clotted into the pores of the material, sealing it and preventing bleeding. In later years this process was improved by the simpler expedient of impregnating the graft in bovine collagen, the tough protein which makes up most of the connective tissue in animals.
Dacron grafts were first used to treat aneurysms of the abdominal aorta, where the blood flow could be safely halted for long enough to replace the affected section of the vessel. Operating on the thoracic aorta, close to the heart, was a more formidable challenge: the vessel supplies the brain, which cannot be starved of blood for more than a minute or two. One ingenious way round this problem was to attach a graft as a bypass around the diseased section of aorta: only after blood had been diverted into this shunt was the diseased segment removed, ensuring that the circulation was never interrupted. But this was laborious and technically difficult; it was only after the adoption of the heart-lung machine in the mid-1950s that surgeons could cut out and replace entire sections of the thoracic aorta with any degree of security. These machines took over the function of the patient’s heart and lungs for the duration of the operation, oxygenating the blood and pumping it through the carotid arteries towards the brain while the diseased aorta was being excised. In the space of a couple of years DeBakey and Cooley succeeded in repairing aneurysms of all parts of the thoracic aorta, proving that no area of the vessel was out of bounds.
Although surgeons continued to experiment with other materials it was not until the 1970s, after the invention of Gore-Tex, that any successful alternative to Dacron was found. Today these polyester tubes are still widely used, although other, non-invasive, methods have also been found to cure aneurysms – a lesion which one recent textbook still described as ‘among the most lethal of conditions and the most difficult to treat’.68
Two centuries separate the contrasting fates of our first two victims of aortic aneurysm: an Italian prostitute and a sheriff from Arkansas. Our last two will be a king of England and Michael DeBakey himself. George II is the only British monarch known to have died while defecating. On 25 October 1760 he rose as usual at six o’clock and called for his morning cup of chocolate. An hour later he went to his water closet, and shortly afterwards – according to his biographer Horace Walpole – the valet heard a groan and a strange noise ‘louder than royal wind’, and rushed in to find the king dying on the floor.69 An autopsy was performed, and the royal physicians found the blood vessels around the heart ‘stretched beyond their natural state’; in addition, ‘in the trunk of the aorta, we found a transverse fissure on its inner side, about an inch and a half long, through which some blood had recently passed, under its external coat.’70
The king had died from a condition known as aortic dissection. Like all arteries the aorta consists of three layers of tissue: in aortic dissection, a weakness develops in the inner lining of the vessel, allowing blood to penetrate into its middle layer. Because arterial blood is at high pressure it can rip the two layers apart for some distance along the length of the aorta; in George’s case the vessel had split entirely from inside to out, killing him outright.
Most patients die immediately or within a few hours of an aortic dissection. Some survive the initial episode, although they are unlikely to live for long. In the 1950s the condition was regarded as another type of aneurysm,fn4 and one made particularly difficult to treat by the lengthy sections of the aorta often involved. In July 1954, DeBakey and Cooley effected the first cure of an aortic dissection, repairing the damage by suturing the tear.71 Although their patient survived they soon realised this method was not ideal, since it left the compromised vessel in situ; with later patients they replaced the affected section with freeze-dried homografts or Dacron prostheses. In the next six years they treated seventy-two patients, three-quarters of whom made good recoveries.72
Many people over the next half-century would have good reason to be grateful for this development; one was Michael DeBakey. In 2005 the ninety-seven-year-old surgeon was sitting at home preparing a lecture when he felt an excruciating pain in his chest. An hour later his wife found him lying on a couch in his office. He told her that he knew what was wrong, and that it was serious. In hospital his colleagues confirmed what he had already worked out for himself: he had an aortic dissection. Only too familiar with the poor survival odds for a patient of his age, DeBakey refused consent for an operation. His family and friends were determined, however, and when he slipped into unconsciousness a special meeting of the hospital’s ethics committee was hurriedly convened. It concluded that the circumstances were exceptional: DeBakey’s assessment of his own chances was needlessly pessimistic, and the views of his doctors and family should be taken into account. The operation was allowed to proceed.
One of DeBakey’s most trusted protégés, Dr George Noon, performed the surgery, using techniques pioneered by his patient decades earlier.73 DeBakey pulled through, becoming the oldest survivor of an operation he invented; a few months later he was often spotted in the hospital gym, obediently following the rehabilitation programme set out by his colleagues. He even returned to work and lived for two more years, dying a couple of months shy of his 100th birthday.
Although this is a book about heart surgery, the organ itself has barely featured in this chapter. Indeed, most people who suffer an aortic aneurysm today will never meet a cardiac surgeon: the aorta is now largely the preserve of vascular specialists. But all the individuals involved in this story went on to make major contributions to the development of heart surgery. The aorta is the largest pipe in an elaborate system of plumbing whose main pump is the heart. And learning how to repair those pipes was an essential prerequisite for fixing the pump itself; barely a decade after the first aortic aneurysm repairs, Christiaan Barnard transplanted his first heart. It was the ground-breaking work of DeBakey and Cooley that made that feat possible.