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DOI: 10.1055/s-2005-837686
© Georg Thieme Verlag KG Stuttgart · New York
Victory by Stages: The “Tour De Force” to Early Correction in Congenital Heart Surgery
Publikationsverlauf
Received February 14, 2005
Publikationsdatum:
22. Juli 2005 (online)
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The period in which cardiac surgery evolved was a period of exceptional discoveries, it developed within my lifetime. There were the pioneers, teachers of some of us, who worked with unlimited energy, clear concepts and an abundance of creative ideas to establish methods for the treatment of congenital cardiac anomalies which over time were to develop into practical concepts which have now spread all over the world.
The pioneer years saw many disappointments and sleepless nights, a lot of frustration and self-reproach because of failures and errors. The only road ahead was to trust in concepts and convictions, to objectively analyse one's own experience or the published data of others; above all, it lay in personal persistence.
These scientific achievements became the basis for the cardiac surgical treatment of children, infants and - nowadays - newborns, the foundation of pediatric cardiology. Today almost any congenital cardiac anomaly can be treated, even though many, operated on as children remain a continuing sorrow. Although at the moment the number of neonates and of infants with complex congenital failures is decreasing, there is still a need for congenital cardiac surgeons, perhaps - since there are indications that the concentration of manpower, knowledge, and experience leads to better results - in a reduced and controlled number of centers.
The increasing understanding of the human genome and the use of molecular genetics will help us to understand the causes of congenital cardiac anomalies, thus preventing their origin - but not in the near future. The progress achieved during the past century in this particular field of surgery is incredible and worthy of a retrospective review.
Surgical therapy for congenital cardiac diseases started with palliation. The first really revolutionary operation was performed on November 29, 1944 on a 15-month-old female infant with Tetralogy of Fallot (TOF) by Alfred Blalock at the Johns Hopkins Hospital in Baltimore. The idea for this life-saving shunt operation was developed by Helen Taussig - a deaf pediatrician, so the story goes - and a blind surgeon. Indeed Helen Taussig needed a special auscultation device and because of severe myopy Blalock used very strong spectacles when operating. That, at least, is the story. Actually Blalock, together with S. E. Levy and Vivien Thomas, had operated on dogs some time before, at Vanderbilt University in Tennessee, where he constructed left subclavian-pulmonary shunts imitating open ducti and attempted to create pulmonary hypertension.
A similar operation to improve the prognosis for cyanotic heart disease was performed by Willis John Potts in Chicago (November 1946), after he and his instrument maker Sidney Smith had constructed his famous clamp. In Europe, T. Holmes Sellors and Russell Claude Brock, in different London hospitals, initiated a transventricular approach to increase pulmonary blood flow, the first on December 4, 1947, the second in February 1948.
In January 1948 Alfred Lord Blalock gave the first Rudolph Matas Lecture in New Orleans, reporting on his experience with 610 cyanotic children operated on with TOF in whom he was able to demonstrate a decrease of mortality from 23 % to 17.7 % [[1]].
The era of open heart surgery was led off in Toronto, where Wilfred G. Bigelow had started experimental hypothermia in dogs and monkeys in 1947. Existing metabolic studies, e.g. of Grosse-Brockhoff and Schoedel in Düsseldorf in 1943, had shown an increase of metabolism whereas others had noted a decrease. Bigelow established an almost linear relationship between metabolism and body temperature, demonstrating a fall with cooling which thus allowed open heart surgery. The anesthesia method turned out to be quite important. Without doubt W.G. Bigelow was the pioneer of hypothermia.
On the basis of these experiments John F. Lewis and M. Taufic in Minneapolis closed the first ASD in 1952 in a 5-year-old girl using surface cooling. During the following years many cardiac centers around the world applied this new technique successfully. Between 1950 and 1962, Bigelow and his team continued to work on the secret of hibernation: he set up a groundhog farm where they studied the hibernating animals, isolating a so-called “groundhog extract”. Bigelow and his team believed they had discovered the hormone of hibernation. However, before they published this exciting news, they realized that the substance they had extracted was a plasticizer … what a shock … yet another blind alley [[2]].
In Europe the surgical treatment of congenital cardiac disease became possible a few years after the Second World War, around 1949. The operations carried out were PDA, coarctation, constrictive pericarditis, Blalock-Taussig shunts, and some closed commissurotomies on a stenosed mitral or even aortic valve. Experimental studies for open heart surgery were initiated by Ernst Derra in Düsseldorf who started an experimental program on hypothermia in the early 1950s, closing an ASD on February 2, 1955. This was the first successful open heart operation in man in Europe. In 1956 Rudolph Zenker in Marburg started an intensive experimental program on extracorporeal circulation under the guidance of Hans Georg Borst; as a result an ASD was closed using a heart-lung machine on February 19, 1958. Further details are given in Borst [[3]] and Bircks [[4]].
On April 25, 1958 Zenker closed a VSD using a transventricular approach and direct sutures. His next successful operation was correction of a partial a-v canal on June 7, 1958 in which he closed the ostium primum defect with an Ivalon patch [[5]]. A surgical symposium on VSD was held on October 31, 1958 in Bad Godesberg, the chairman was Georg Heberer; the discussion focussed on two operated patients [[6]].
In several hospitals around the world the era of open heart surgery, using extracorporeal circulation, had begun. First results began to be published and discussed: thus, in July 1958 the American College of Chest Physicians had collected the data of 2439 patients with Tetralogy of Fallot. Mortality for palliation varied between 13.8 % and 26.7 %, for HLM repair it was 39.3 % [[7]]. The conclusions were that it was necessary to gain time in treatment, apply palliation according to anatomy and clinical state, and carry out operative corrections only under optimal conditions. The recommended age for this procedure was 5 years or more. These were the first steps towards a surgical therapy for a difficult anomaly, rather small steps indeed, and in the beginning, in many patients with TOF the VSD was closed without a patch.
In general, operative treatment for congenital cardiac disease spread slowly. About a decade later, in 1967, the operative treatment of an isolated VSD had a mortality for banding of 20 % compared to correction with 27 %. The recommended age for operation was 2 to 5 years [[8]].
In Germany, at that time, cardiac operations were possible at 11 university hospitals, although only six were able to offer a full program. Tetralogy of Fallot was corrected successfully by Zenker in Munich on February 20, 1959 [[5]]. His pupil, Werner Klinner, after some time at the Mayo Clinic, had gathered extensive experience in the treatment of that disease: within a period of 10 years 367 children were operated on and the initial mortality of 27 % had decreased to 12 %, which was in the range of that of international top surgeons [[9]]. Still, the recommended age for operation was 8 to 16 years.
John W. Kirklin, who had started intracardiac operations in 1955 at the Mayo Clinic in Rochester, and who had taught an innumerable number of surgeons the secrets of correction of Tetralogy of Fallot, moved to Birmingham, Alabama in September 1966, where I had the chance to visit him. As a visitor from Europe one was accepted with great enthusiasm, in particular also by the chief of anesthesiology Günter Corssen, who had been a tank driver in the former German army. Kirklin operated on a patient with TOF, skilfully and superbly, but with slow movements, always asking the anesthetist to read the different steps of the operation from his own book, thus guaranteeing a safe and reproducible technique which would be teachable and present acceptable results. An original drawing by his own hand is given in Fig. [1] a, while W. Klinner sketched his technique at that time as shown in Fig. [1] b.
Fig. 1 a, b Original drawings of the operating technique applied for correction of TOF by a J. W. Kirklin and b W. Klinner.
During the decade until the 1970s mortality remained high both for correction and for palliative surgery. Infants below one year of age were at even higher risk, here palliation was carried out in a few clinics only.
A cardiac disease causing specific concern was transposition of the great arteries (TGA). Looking at the fascinating history of this anomaly it appears that the expression “tour de force” is justified: The first steps are linked to the name of Åke Senning. He, a daring and outstanding surgeon with many innovative ideas, constructed the second heart-lung machine in the world in Stockholm. The first operation carried out with his machine, initially with the diagnosis of mitral disease, turned out to be a myxoma of the left atrium, but was managed by Clarence Crafoord and Viking O. Björk with superb competence. Åke Senning's pump performed perfectly. This young surgeon had studied the current literature on TGA, reading the experimental work of H. M. Albert from 1954. Applying and modifying these ideas, in 1959 he corrected cyanosis in a 9-year-old boy with TGA by changing the inflow to the atria: the technique of atrial inversion using the heart's own material was born. It appeared however that Senning was too much ahead of his time: his ingenious technique was too complicated and not accepted and copied for some time to come.
At the University of Toronto there was a pediatric surgeon named William T. Mustard, who worked in orthopedics and had already developed an operation bearing his name: the ileopsoas tendon transfer for children after polio. In 1951 this surgeon became interested in the new surgery of the heart, in particular the anomaly of TGA. After many animal experiments and unsuccessful switch operations (1955) he turned to the principle of atrial inversion: on May 16, 1963 he operated on an 18-month-old girl using the pericardium for atrial inversion, his assistant was George A. Trusler. This operative approach turned out to be simpler and easier to understand than Senning's ingenious mode of tissue assembly. The method spread quite rapidly; in London, for example, at the Children's Hospital at Great Ormond Street in June 1965 9 children were operated on, using Mustard's technique. Six survived; it was a sensation and the BBC spread the news all over the country.
Mustard himself, in the meantime, had built a 1.6 m high, transparent plastic model of the atrial chambers with the baffle inside to help explain the complicated operation to his students, colleagues, and guests (Fig. [2]). Mustard was not only brilliant, he was a tough guy indeed; he was the only pediatric cardiac surgeon I know of, who could perform a single arm push-up, he also operated with a bleeding stress ulcer up until shortly before his collapse [[10]].
Fig. 2 Photograph of W. T. Mustard demonstrating his transparent model of the atrial baffle operation (with permission of the Toronto Star).
Up to 1971, about 1000 such operations had been published. While this was certainly a big step forward, the reports rarely dealt with newborns and infants. In Germany, palliative surgery, that is, the ingenious and complicated method of Blalock-Hanlon, was generally applied. The team in Düsseldorf, for instance, published data on 110 palliative operations with an overall mortality of 20.9 % [[11]]. The results reported from across the Atlantic for infants were no different [[12]], that is, the treatment of infants, under one year remained a matter of concern. In Germany the first atrial inversion was done by Josef Koncz in Göttingen in 1964 [[13]].
A “teaching place” of great importance for us Europeans was the Hospital for Sick Children in London, Great Ormond Street, where David Waterston and Eoin Aberdeen had established a great service for the treatment of all congenital cardiac anomalies, in particular TGA [[14]]. Many cardiac surgeons visited to attend courses in cardiac surgery by the British Council. The London group also led the field in the postoperative intensive care of infants, with very efficient therapies for long-standing pulmonary and ventilatory problems, although these required large numbers of staff. In these years between 1963 and 1973 many ideas, tricks, and techniques thus found their way over the British Channel. Overall the mortality rates for palliative and corrective congenital cardiac surgery varied, depending on the experience of the team and the complexity of the disease. Reports on operations on infants under one year of age however were few.
Between 1963 and 1971 some groups in Japan, in particular from Kyoto and Tohoku University, published extensive experimental work on the combined technique of surface hypothermia and extracorporeal circulation, which was finally applied for correction in infants under one year of age. The results were convincing. The procedure and data were summarized in an International Symposium in New Zealand in February 1972, organized by B. G. Barrat Boyes and J. W. Kirklin. The new approach consisted of surface hypothermia cooling the patient to 30 °C or below, then opening the chest and instituting extracorporeal bypass and cooling to about 20 °C. For correction cardiac arrest was preferable, not exceeding 60 minutes, followed by rewarming of the body by pump and surface means. With this technique mortality in infants with VSD decreased remarkably, e.g. only 6 out of 36 died and only one out of 12 infants [[15]]. These achievements must be seen as the basis for early correction; a remarkable step forward had been achieved.
With this method correction of all symptomatic anomalies could be attempted. The results depended on the experience of the team and the complexity of the failure, but not on the age of the patient. At that time the question of silent brain damage was already being discussed; now, after 30 years, this remains a moot point in our research.
At the time news did not spread as fast as it does today. Information and knowledge of the new technique disseminated slowly and some time passed until the concept met with more general acceptance. In our hospital in 1974 a randomized study was initiated in 41 infants, with a mean body weight of 5.64 kg, using either surface cooling or core cooling and circulatory arrest, during which the metabolic events were registered. The results were in favour of core cooling with ECC, the technique that is applied today [[16]]. Thus it became possible to carry out corrective surgery in children under one year of age with the diagnosis of TGA, CCAVSD, or other rare anomalies like IAA or TAPVC, anomalies which were at that time linked to a very high mortality.
The next meeting of significance was 1981 in Bergamo, a symposium under the direction of Lugio Parenzan on surgical therapy of children up to 3 months of age [[17]]. It was demonstrated that early correction of VSD and also of CCAVSD was superior to the commonly applied two-stage technique, that is, primary banding and then correction. The same holds true for early repair of TOF, provided a favourable anatomy is present.
From that point on, early correction begun to outrank palliation. In some clinics this occurred in tiny steps, in others with bigger steps, sometimes as a “tour de force”. Many scientists contributed to these progressive developments. Fig. [3] shows an original drawing of Alain Carpentier of Paris. Many considerations and ideas led to new steps: after years of experimental work on the treatment of missing right heart failures, Francis Fontan and Eugene Baudet in 1968 finally succeeded in operating on 7 patients, 3 of which survived. During the following years a few more patients were operated on, the first patient treated in Munich was operated on by Fritz Sebening in July 1974 [[18]].
Fig. 3 Technique of correction of total a-v canal, drawing by Alain Carpentier.
The main reason for the hesitant approach was the difficult postoperative care of such patients after a cavopulmonary connection. It took more than 10 years to obtain satisfactory results.
Continued progress permitted the early repair of transposition of the great arteries, at least in a few hospitals. Already in 1973 intense discussions led to the Mustard operation not being carried out within the first and second year of life, while some centers such as Göttingen, Hanover, or Munich could demonstrate very respectable results. In 1977 Gerard Brom and Jan Quaegebeur in Leiden initiated a revival of A. Senning's technique. Some doctors, including us, were attracted by their ideas and assumed that new lines of incision and a new suturing technique without foreign material would be superior to Mustard's pericardial baffle, expecting in particular fewer atrial arrhythmias. Today we know that the re-operation rate due to baffle obstruction is lower, but there is no significant difference with respect to arrhythmias.
For TGA and VSD Adib D. Jatene in 1975 and Magdi H. Yacoub in 1976 successfully introduced the switch operation. Repair of TGA with intact ventricular septum was still unsuccessful in 1972. Yacoub solved the problem of the low pressure in the left ventricle by performing pulmonary artery banding first, thus training the ventricle for the systemic load. Soon, however, it could be demonstrated that the switch operation was possible within the first few days of life without additional surgery [[19], [20]]. Our experience with anatomical correction with TGA and VSD dates back to May 1983 and, in infants with an intact ventricular septum, to March 1985 [[2]]. We faced the dilemma that atrial inversion had a mortality rate of below 2 % compared to the new switch technique which had a 6- to 8-fold higher mortality rate. In April 1986, at the meeting of the American Association of Thoracic Surgery in New York G. A. Trusler of Toronto and J. P. Binet of Paris defended the low mortality atrial inversion procedure and demanded an overall mortality of less than 10 % for arterial inversion, which was reported only by A. R. Castaneda and J. M. Quaegebeur [[22]]. More experience was needed and a few centers were willing to follow the new path ahead. Then in 1987 Richard A. Jonas and his team in Boston presented scientific proof for the feasibility of the switch operation in neonates. Finally in 1991 the same group reported a mortality rate of 3.2 % for age ranges between 4 weeks and 21 months. That indeed was the breakthrough of the switch operation. Sixteen years after the first successful arterial inversion the atrial inversion procedure was discontinued for the treatment of TGA. This indeed was a great step forward, which many regarded as a tour de force. Some original drawings are shown in Fig. [4].
Fig. 4 a - c Surgical drawings of the arterial switch operation by a Jatene, b A. Castaneda and c R. Mee, initiator of the trap door technique for coronary implantation.
An ongoing survey of the results of congenital cardiac surgery in Germany is possible using the data collection of our Society initiated by Georg Rodewald in 1978 and continued up to the present day by his pupils [[23]]. Fig. [5] classifies the children operated on between 1978 and 2003 according to age: in 1978 only 7 % of the operated group were younger than one year of age, while already in 1987 the percentage was 28 %, and this has continued to rise in the years to follow. When we look at some of the different defects, TGA in particular demonstrates clearly the stages until early correction (Fig. [6] a). In 1978 27 % were under one year of age at the time of correction, in 1987 this figure was already 87 %, and in 2002 it was 93 %, a continuous rise extending over two decades. In patients with total a-v canal, separation of the two curves occurred about ten years ago; the continuous increase in the number of operations in patients younger than one year of age is obvious (Fig. [6] b). Progress was much slower in patients with TOF: even with a continued increase of operations below one year of age separation of the two curves only took place in the last decade (Fig. [6] c). These curves, calculated from the “Hamburg statistics”, illustrate the slow and careful process of decision-making in the various centers of cardiac surgery. Certainly a multifactorial process is involved, influenced by technical developments, the number of referrals, and the progress and experience of the team of cardiologists and surgeons. This is emphasized in Fig. [6] d, which summarizes the mortalities of infants for the different anomalies under discussion reaching a 5 % threshold at different periods.
Fig. 5 Actual number of congenital cardiac operations in infants in Germany under one year of age carried out between 1978 and 2003, calculated from the survey of the German Society of Thoracic Cardiovascular Surgeons. The total number of children is indicated by a dotted line. The number of units is listed below (U).
Fig. 6 a - d Number of children below (▪) and above (□) one year of age, calculated from the survey of the German Society for Thoracic and Cardiovascular Surgeons [[23]], operated upon with the diagnosis of TGA (a), of CAVSD (b), of TOF (c). d Summary of hospital mortality of infants operated on in Germany between 1986 and 2003 with different diagnoses (TGA, CAVSD, TOF, VSD), calculated from the survey of the GSTCS [[23]].
A particular challenge are inoperable anomalies. They stimulate the intuition and creativity of researchers and scientists to find a means permitting some form of surgical treatment. Thus in the beginning of 1980 William I. Norwood described the technique which bears his name and permits the surgical treatment of the up to that time uncorrectable hypoplastic left heart syndrome. Initial mortality was high and in Germany only a few centers such as Gießen and Bad Oeynhausen followed this path, most centers with reluctance. Ten years later, by 1993 143 newborns had been operated on.
The concept of Fontan's operation, included in that treatment, was improved more and more with a variety of different methods, in particular Glenn's anastomoses. Using these refined techniques early correction of such complex anomalies such as IAA, BWG, or CCTGA became possible.
Quite early on, the introduction of prostaglandin E1 and later the knowledge of Endothelin and the use of NO proved to be very helpful; one cannot deny the additional therapeutic effect of coils or stents or the introduction or possibility of homografts. These are just a few advances in the evolution of new methods forming part of the chain of surgical treatments for congenital cardiac anomalies.
The road from palliation to early correction was a long one. Our scientific knowledge permitted only small steps to be taken, but sometimes leaps were also possible. Limiting factors are always the motoric possibilities and the competence of the surgeon. Today, an experienced surgeon operates without surgical failure; that is the standard he sets himself, his ambition. Carefully designed intra- and perioperative protocols provide a certain margin of safety, so that if something unpredictable happens the surgeon's intuition will help get him out of the difficulty. Intuition will trigger a certain program of behaviour, based on knowledge and experience, some of it subconsciously.
The self-induced discipline of the surgeon not to tolerate any failure can be irritated by the fear of failure. Despite optimal knowledge and surgical skill errors will occur; John Kirklin named this risk “human error” [[24]]. There will always be our silent and obstinate fight against human error.
We reach and reached our victories in small steps, and many times despite high obstacles; painful questions trouble our conscience and tough decisions accompany our sometimes quite risky tour de force in search of further progress. In the end, all steps were a part of our victories, whether great or small.
The philosopher Friedrich W. Nietzsche said in his book “Fröhliche Wissenschaft”: “The best of a great victory is that it absolves the victor from the fear of a defeat”. This is the way it should and will be in the future for congenital cardiac surgery: progress will continue, and there will always be those who will struggle anxiously and apprehensively before continuing to operate on an infant and perhaps risk something new but promising.
A review of more than a half century of congenital cardiac surgery highlights the results achieved to date, which are impressive. Indeed we can be proud of our history, standing on the shoulders of those who went before. And this history can serve to encourage our successors: progress is also nurtured by a few defeats and this progress will be considered by history and mankind as a victory.
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Prof. Dr. Hans Meisner
Arnikaweg 6
82335 Berg-Aufkirchen
Germany
eMail: franz.meisner@online.de