For those who became students of the field of congenital cardiac surgery in the last two decades, there were two obvious role models. They were positioned one on each coast of the United States of America, both white haired at very early ages, both clever and intuitive, innovative, determined, hard-working, and both very strong believers in fundamental principles. One of these, Len Bailey, is here today, and will be presenting the other side of this debate. I will do my best to advance the cause that was pioneered by the other of those two white-haired gentlemen, Bill Norwood, who promoted staged reconstructive surgery as primary therapy for hypoplastic left heart syndrome. In the spirit of trying neither to win nor lose the debate, I have chosen to try to describe the characteristics of a good surgical solution to a very challenging problem. These characteristics are that the surgical solution should be widely available to meet the need, that the therapy should be based upon sound physiologic principles, it should be readily taught and learned, and should be reproducible. The product of the therapy should be durable, it should afford a satisfactory quality of life, and should provide the foundation for continuous improvement.

With regard to staged reconstructive surgery based on the initial first stage of Norwood palliation, let's look at the question of availability. It is a tough surgical problem. At the beginning of the 1990s, this form of treatment was available at a few major regional congenital cardiac centers scattered throughout the United States of America. But now, in 2003, it is widely acknowledged that virtually every major metropolitan area in the United States, many throughout Europe, many in Japan, a few in Canada, and a few in South America, offer this kind of staged reconstructive surgery with steadily improving results. That feature of availability must be compared with the alternate form of therapy. Figure 1 is reproduced from an article that was co-authored by Dr Bailey and myself,¹ which presented the results of a multi-institutional study on outcomes in neonates with aortic atresia. It was undertaken by the Congenital Heart Surgeons Society. The figure represents the non-risk adjusted survival of patients at four centers. The study itself involved 21 centers. There were four centers that were identified as being “low risk”. Two of those centers were committed to transplantation as primary therapy. The other two were committed to staged reconstructive surgery. Why would I show you a graph where the survival looks a little better for the protocol based on transplantation than it does for reconstructive surgery? The answer comes from reading between the lines. The dotted lines, the confidence limits, show that these curves differ only by an amount that can be no more than that accounted for by chance. What is more important is the story behind the graph. This was a retrospective study. It involved the enrollment of 323 neonates at 21 centers over the period from 1994 to 1997. The ultimate analysis was based upon intention to treat. That means intention to enter into a protocol either for transplantation or reconstructive surgery. Of the 323 patients, 49 were entered into the protocol for transplantation, and 253 into the protocol for staged reconstruction. Of the 49 with an initial intention to treat by transplantation, 42 of them were seen in three centers. The remainder were scattered at a few centers around the country. It proved possible eventually to perform 36 transplants, with the remaining 13 patients either crossed over to palliative surgery, taken off the transplant list, or dying without transplantation. While transplantation may represent an excellent form of therapy, its promise remains unfulfilled because of the severe limitation of availability of donor organs. Staged reconstructive therapy has become a predictable, and nearly universally available, form of therapy. That, of course, is one of its principle strengths.

Figure 1. Non-risk adjusted survival of patients entered into treatment protocols at the four low-risk institutions in the Congenital Heart Surgeons Society study of outcomes in aortic atresia. The 70% confidence intervals converge at a point approximately one week after entry and continue to overlap thereafter. (From: J Thorac Cardiovasc Surg 1998; 116: 417–431.)

The second characteristic of a good surgical solution is that it is based on sound physiologic principles. During the course of this symposium, you have already heard very astute people like Anthony Chang analyze the characteristics of the circulation that results from first stage palliation (see pp 52–60). Clinical experience has completely born out the predictions that followed from early engineering modeling of the Norwood circulation by such authors as Erle Austin and his associates at Louisville.² And post-operative management of the palliated circulation has been refined and improved based upon an understanding of the mathematical modeling of this physiology by Migliavacca and his associates,³ and by clinical investigations in the post-operative cardiac intensive care unit by Hoffman and his associates,⁴ among others. It is, in fact, the sound physiologic principles upon which the reconstructive surgical strategy is based that allows us to manipulate the situation seen after first stage palliation to achieve the most satisfactory outcome. A decade ago, the investigators with whom I worked in Philadelphia devoted a lot of energy to efforts to manipulate the pulmonary vascular resistance to achieve a salutary balance of systemic and pulmonary flows of blood after initial palliation. Others have shown more recently that it may be easier, and more predictable, to manipulate the systemic vascular resistance, as pharmacologic agents to achieve this goal are more readily available. But the principles which make this operation succeed or fail have not changed over time. It is our ability to grasp the principles, understand them, and apply them that has accounted for the steady improvement in outcomes. Furthermore, with regard to the complete protocol for reconstructive surgery in hypoplastic left heart syndrome, it is fair to say that the initial efforts to treat these patients by means of a Fontan pathway really laid the groundwork for the staged approach to construction of the Fontan circulation, with early removal of the ventricular volume load, that is now nearly universally applied as therapy for all patients with functionally single ventricles. The very low mortality for the second and third stage procedures, the hemi-Fontan and the completion Fontan procedures, add validity to the very labor intense initial management of these infants by mean of palliative surgery.

I made the assertion that a good surgical therapy must be readily taught, readily learned, and should be reproducible. I think that the track record for palliative surgery for hypoplastic left heart syndrome has just those characteristics. While Bill Norwood is widely acknowledged as the principal primary proponent for initial palliation and staged reconstruction for hypoplastic left heart syndrome, his unique contribution was viewed by many with a good deal of cynicism. One cannot overlook the immense importance of the contributions of others who followed shortly afterwards, such as Ed Bove at the University of Michigan, who early on published very candid reports reflecting hospital survival for less than half of those undergoing first stage palliation during the period of 1986 through 1989, but followed shortly thereafter by reports of dramatic improvement to hospital survival, so that almost nine-tenths survived in the period from 1990 to 1993. For Norwood's operation to be widely accepted, it was essential that other surgeons and investigators at other centers be able to achieve comparable results. The kind of significant improvement and eventual excellent outcomes reported by the University of Michigan group were eventually echoed by those working in Toronto, Boston, Milwaukee, and Birmingham in the United Kingdom. They are now achieved at pediatric cardiac centers in most major metropolitan areas.

Is the therapy durable? Experience over the past decade has demonstrated that the therapy based on staged reconstructive surgery for hypoplastic left heart syndrome is indeed durable. The late mortality after completion of the Fontan operation is very low. This is reflected in the report by Mahle and associates⁵ from the Children's Hospital of Philadelphia, who analyzed the outcome of 15 consecutive years of surgery for hypoplastic left heart syndrome. Nearly 300 patients were discharged home after Fontan operations. The late mortality for the Fontan operation, with maximum follow-up of 15 years, was just about 5%. There had been only one late death more than five years out from surgery. It is important to note as well that just 2% of the patients had gone on to transplantation. While the first successful initial palliations were done by Norwood just two decades ago, current evidence suggests that this is a very durable form of therapy. It is important, however, to also consider late morbidity, which is primarily accounted for by sinus nodal dysfunction and subsequent arrhythmias, by the occurrence of protein losing enteropathy, which has fortunately been quite low, and by thromboembolic events.

Part of the essential durability of a therapy is the ability for surgically created pathways to grow with the patient. The Philadelphia group documented very clearly that growth of the augmented aortic arch paralleled the growth seen in the normal population. And, in a careful analysis of post-mortem specimens, they documented that it is the remnant of native aortic tissue that is present at all levels in the reconstructed aorta that accounts for the growth and increase in circumference of the neo-aorta.⁶

How about quality of life? What do we know about neuro-developmental outcome, and lifestyle assessment, after staged reconstructive surgery? In 2000, the group from Children's Hospital of Philadelphia reported follow-up of 115 children aged around 9 years who had undergone staged reconstructive surgery for hypoplastic left heart syndrome.⁷ The parents described academic performance as average, in two-fifths, or above average in another two-fifths, with one-third of children receiving some form of special education. The median full-scale intelligence quotient was in the low to normal range. The majority of patients were in the normal range, but as for most populations with congenital cardiac disease, the mean was somewhat lower than that for the general population. Another survey was done by the group at the University of Michigan, looking at all of their patients with a Fontan circulation.⁸ The mean full scale intelligence score was 101, for the groups with hypoplastic left heart syndrome being 94, and for those with lesions other than hypoplasia of the left heart being 107. Although those with hypoplastic left heart had lower scores than the others, neither sub-group scored significantly different from the standard population. In our own practice at St. Christopher's, we have recently undertaken an assessment of the quality of life in the group of patients on whom I had completed reconstructive surgery for hypoplastic left heart syndrome more than a decade ago. We follow 20 children, now aged 11 and 12 years, and sent them and their parents a questionnaire and a standardized tool to assess the health-related quality of life during childhood. The majority of parents rated the overall health of their child as good or excellent, and none were rated as poor. The majority of these children are in a regular class at school appropriate for their age, with about one-third of them in regular class with some additional special education. One is being schooled at home, and one requires special schooling. School performance was rated by the parents as being above average for more than half the group, and either average or below average for the remaining half. Most were rated as being as active as other children. Importantly, the parents acknowledged that some of these children do have problems with comprehension, verbal expression, gross and fine motor skills. The tool used was sent both to the children and their parents. Interestingly, in term of physical quality of life, the children tended to rate themselves as being equivalent to healthy children who have used this tool in other assessments. In terms of their emotional, psychological, and neuro-developmental health, they tended to rate themselves as being roughly comparable to groups of patients who have chronic non-life threatening diseases with good prognosis. The parents scored it slightly differently than did the children. The parents were less overwhelmingly impressed with the physical prowess of their children, but were equally impressed with their general well-being. The children were asked several general questions about their strengths and weaknesses, their likes and dislikes. No one could read these responses and fail to come away with a heart-felt appreciation for the value of the intensive medical effort during the first two years of life that eventually resulted in this expressive group of children now aged 11 and 12.

The initial premise in this debate was the belief that I could convince you that staged reconstructive surgery for hypoplastic left heart syndrome is a viable, important, and satisfactory form of therapy if it meets certain criterions. It is sufficiently widely available to meet the need. It is based upon sound physiologic principles. It is readily taught, readily learned, and reproducible. It is durable, and it affords a satisfactory quality of life. What we have learned at this symposium, which is very encouraging, is that it also provides the foundation for continuous improvement. Staged reconstructive surgery for hypoplastic left heart syndrome continues to evolve, with new strategies for cardiopulmonary bypass, and refinements in peri-operative management. The operations themselves evolve, as represented by the recent re-introduction of the conduit placed from the right ventricle to the pulmonary arteries as part of initial palliation. This may result in a more durable, more forgiving, circulation permitting less challenging post-operative management, and perhaps a higher rate of survival. And, of course, as is often the case when different pathways are pursued toward a common goal, many of the strategies that have evolved to optimize the management of patients awaiting transplantation have led also to improvements in the outcome for palliative surgery. The intertwining of the benefits of these distinctly different therapeutic pathways is immense. Hence, my belief that the debate over reconstructive surgery versus heart transplantation for hypoplastic left heart syndrome is a “win-win” proposition.