How Did Denise Darvall Die? A Contribution to the History of the First Heart Transplant

Abstract

The first heart transplantation, performed by Christiaan Barnard in 1967, was one of the most important medical events of the twentieth century. The real significance of the operation, beyond the surgical feat, was setting a precedent for the reinterpretation of death and introduction of the controversial concept of “brain death.” Contemporary public acceptance of this concept was supported by the general belief that, according to the newly created criteria, Denise Darvall, the first heart donor had been brain-dead, and her heart was procured when cardiac arrest occurred after stopping mechanical ventilation. However, there are doubts whether Denise was really brain-dead. Moreover, Barnard's brother, Marius confessed that Denise's heart was stopped with potassium injection, although he later retracted this claim. To clarify these issues, data related to the first heart transplant were collected. Taken together, the data suggest that the first heart donor, whose case set a precedent for organ removal from “brain-dead” patients, was not in fact “brain-dead” in today's term, and, moreover, her heart may have been arrested artificially, similarly to a non-voluntary active euthanasia.

Non-technical summary

According to a widely held view, Denise Darvall, the donor of the world's first heart transplant, was a brain-dead victim of a car accident, and her organs were explanted when cardiac arrest occurred. However, there are serious doubts both about her brain death and spontaneous cardiac arrest. This research revealed that Denise, whose case set a precedent for organ removal from brain-dead patients, was almost certainly not brain-dead and her heart was arrested with potassium injection. These results suggest that Denise Darvall's death was similar to a non-voluntary active euthanasia.

Short summary

Data related to the first heart transplant suggest that the donor was not brain-dead and her heart was arrested artificially, similarly to a non-voluntary active euthanasia.

“For there is nothing covered, that shall not be revealed; neither hid, that shall not be known.” (Luke 12:2)

In the late 1960s, a number of Western cardiac surgeons, mainly Americans, were prepared to perform the first human-to-human cardiac transplant. The most noted pioneers in this field were Norman Shumway and Richard Lower at Stanford University, California, who had performed hundreds of experimental canine heart transplants since the late 1950s using heart-lung machine and topical hypothermia, and elaborated the method of cardiac transplantation (Dong et al. 1965).

How did it happen that the first to transplant a human heart was not an American or European surgeon? The major obstacle was not the technical challenge but the lack of suitable donor due to contemporary worldwide regulation, which defined death on cardiorespiratory criteria (Barnard and Simon 2011). A heart taken from a cadaver fulfilling the traditional death criteria would not have had a chance to survive and function well after transplantation because of myocardial damage caused by oxygen deprivation during the dying process. On the other hand, removal of a still beating heart could have resulted in serious legal consequences.

Circumstances in South Africa were different, according to Raymond Hoffenberg, who in 1967 was a member of staff at the Groote Schuur Hospital, the academic hospital of the University of Cape Town's Medical School, and later became a renowned professor of endocrinology in Britain. Brain death was not accepted as death in South Africa either, but “public opinion was more permissive” than in the Western world, so the removal of the heart was not supposed to “arouse such strong feelings of abhorrence” and “there was less likelihood of criticism that this would, in fact, ‘kill’ the donor” (Hoffenberg 2001). Additionally, “there would have been less accountability had the operation failed.” And last but not least, “the standard of medicine in Cape Town in the 1960s was advanced and sophisticated” with “well-equipped research laboratories and an ethos in which research and initiative were encouraged,” and also with well-trained doctors, many of whom “were sponsored to go on overseas visits to keep abreast of new advances and disseminate their knowledge on their return” (Hoffenberg 2001).

In Christiaan Barnard, South Africa had such a well-trained, talented, and ambitious surgeon who had brought the American know-how of heart surgery to South Africa (Barnard and Simon 2011; Brink and Cooper 2005; Cooper 2017; McRae 2007; Toledo-Pereyra 2010). He had extensive training in heart surgery in 1956–58 with Walton Lillehei in Minnesota whose innovations revolutionized heart surgery and paved the way for heart transplantation. Returning from America in 1958 with a heart–lung bypass pump machine and an oxygenator donated by the US government, Barnard established the cardiac surgery unit of the University of Cape Town at the Groote Schuur Hospital, which soon entered the forefront of cardiac surgery in the world, with particular expertise in the correction of congenital heart defects and in valve surgery. Eight years later, getting interested in heart transplantation, he had the opportunity to learn the fundamentals of immunosuppressive therapy during his three month-visit at the Medical College of Virginia in Richmond, and, more importantly, to observe Lower's (who left Stanford in 1965 to head the cardiac program in Richmond) experimental canine heart transplantations. Returning to Groote Schuur Hospital, Barnard started to practice heart transplantation on dogs with his younger brother and colleague, Marius, applying the method of Shumway and Lower. In order to get personal experience in the management of immunosuppressive therapy, Barnard performed his first and last kidney transplantation on October 8, 1967. The patient survived for more than twenty years; this was South Africa's first long-term survival following kidney transplantation (Barnard 1995). Although the number of experimental canine heart transplantations performed by the Barnard brothers as well as their survival results lagged far behind those of Shumway and Lower, all the necessary conditions were present to attempt a human heart transplant. Thus, Barnard was waiting for a suitable donor to perform the operation. ¹

On December 2, 1967, 25-year-old Denise Darvall and her mother were run over by a driver in Cape Town. Her mother died immediately. Denise was admitted to the Groote Schuur Hospital at 4 p.m. with severe brain damage. Obtaining her father's consent, Christiaan Barnard transplanted Denise's heart overnight into Louis Washkansky, a 54-years-old patient suffering from end-stage heart failure due to multiple antecedent heart attacks resulting from diabetes and smoking.

Denise was an optimal donor, being young and otherwise healthy, but Washkansky was a problematic choice because of his diabetes and relatively advanced age. Both of them were white (Caucasian), which was also an important issue, since Barnard and his colleagues were afraid of being accused of racism by the political critics of the apartheid state of South Africa, misinterpreting the operation as “using” the organ of, or “experimenting” on a “non-white” patient (Barnard and Simon 2011; Cooper 2017).

Barnard gained overnight fame after the operation and became a celebrity. His life abruptly changed, including his private life (Cooper 2017; McRae 2007; Toledo-Pereyra 2010). Although the world's first human-to-human heart transplant was successful, Washkansky died of pneumonia on the eighteenth postoperative day, after mistakenly being treated for rejection with intensified immunosuppressive therapy (Barnard 1968; Brink and Cooper 2005; Cooper 2017).

For his groundbreaking operation, Barnard employed the technique of open-heart surgery developed by Lillehei and others, and the method of heart transplantation elaborated by Shumway and Lower. Barnard's most important contribution was to facilitate the societal and legal acceptance of brain death concept, i.e., the acceptance of irreversible brain destruction as real death (Altman 2001; Cooper 2017). Within one month of the operation, in the midst of the debate in the media and public discourse on the ethics of organ procurement, Harvard Medical School took the initiative and set up an Ad Hoc Committee, which published its report on August 5, 1968, defining irreversible coma, apnea, missing reflexes and flat EEG as “brain death” – that is to say, real, biological death, even if the patient's heart is still beating and most of the other organs still functioning with some artificial aid (Beecher et al. 1968). ² The background of the formation of the Harvard Ad Hoc Committee and the details of its controversial operation can be found elsewhere (Giacomini 1997; Wijdicks 2003). Suffice it to say here that the first heart transplant undoubtedly brought the ethical aspects of organ removal to the forefront of lay interest and the obvious purpose of the Committee's redefinition of death was to provide a legal basis for organ donation by bringing it into line with the “dead donor rule” (an unwritten ethical principle based on the 5th commandment, according to which vital organs may only be removed from the dead) as well as to get society to overlook its ethical difficulties.

After more than half a century, the Harvard Report, with some modifications, ³ still serves as a base for current legal regulation of death almost all over the world (Greer et al. 2023), even though today it is questioned, for example, whether irreversible destruction of the whole brain is biological death (e.g., Joffe 2009; Jonas 1974; Nguyen 2018, 2022; Shewmon 1998; Truog, Miller and Halpern 2013; Vacca 2023), there are doubts about the diagnostic accuracy of brain death criteria (e.g., Coimbra 1999; Evans 2009; Grigg et al. 1987; Joffe 2007; Joffe et al. 2009; Nguyen and Zainer 2025; Potts 2009; Shewmon 2018; Walker 1976), and the apnea test is subject to scientific and ethical challenges (Joffe 2020). The World Brain Death Project, an international consensus document (Greer et al. 2020), does not share these doubts, rejecting, but – according to the criticism of dissenting experts (Joffe, Hansen and Tibballs 2021) – not refuting them. Perhaps this ambivalence is what the consensus document's authors recognized when quoting with approval the ironic statement that currently the concept of brain death is “well settled yet still unresolved.” Anyhow, it is surprising and unusual that even “strong recommendations” for a medical method that has been used for half a century are based merely on “expert consensus” supported by “limited” and “low quality evidence” (Greer et al. 2020), especially when it is used for nothing less than differentiating life and death. ⁴

Contemporary public acceptance of Harvard's brain death concept was certainly supported by the general belief that, according to the newly created criteria, Denise Darvall, the first heart donor, had been brain-dead, and her heart had been removed when cardiac arrest occurred after stopping mechanical ventilation. But was this public opinion well-founded?

Questions Arise

As mentioned above, many think that Christiaan Barnard's greatest merit was his courage in proceeding with a transplant from a brain-dead person, setting a precedent and laying the foundation for current transplantation practice. Considering the presumed brain death and the fact stated by the case report that organ procurement was delayed until Denise's heart spontaneously stopped, the first heart transplant could meet the so called “donation after brain death followed by circulatory death” (DBCD) protocol in today's terms. Currently, this special protocol is often used in China, where brain death is not universally accepted as real death by society (Huang et al. 2013; Sun et al. 2018). When brain death is confirmed in DBCD protocol, life support is withdrawn; organ retrieval begins after cardiac arrest and a short (usually 5 min) waiting time. In other words, DBCD protocol fulfils the requirements of both the “donation after brain death” (DBD) and the “controlled form of donation after circulatory death” (cDCD) protocols.

However, according to Eelco Wijdicks, it is not certain that all the organ procurements before the Harvard Report were actually from brain-dead patients. “Without actual documentation of a comprehensive neurologic examination and exclusion of confounders, we cannot say with certainty these patients were brain dead” (Wijdicks 2006). This also applies to Denise's case. Furthermore, serious doubts have emerged about Denise's spontaneous cardiac arrest. If both concerns are established, then the first human heart donation resembles an involuntary active euthanasia.

In order to clarify the circumstances of the first heart transplant, especially whether Denise was brain-dead when she was disconnected from the ventilator and whether her heart stopped spontaneously or artificially, a thorough examination of the original scientific publications, a search for additional data related to the first heart transplant, and interviewing some persons with specific knowledge about the case was done with the following results.

Was Denise Darvall Really Brain Dead?

“[E]xtensive investigation… indicated that… she [Denise] had come to the stage of brain death” – Barnard stated in a lecture on the first heart transplant in October 1968 (Barnard 1969), ten months after the operation and two months after the publication of the Harvard Report (Beecher et al. 1968). The validity of this claim, however, can be questioned.

According to one of the papers published in the special edition of the South African Medical Journal dedicated to the first heart transplant, an unnamed neurosurgeon considered Denise's “cerebral lesion as lethal and beyond treatment” (Ozinsky 1967). Obviously, this statement is not equivalent with the current determination of brain death that is based on irreversible coma, irreversible loss of brain stem reflexes and apnea. None of them except coma has been described in contemporaneous reports of Denise's case (Ozinsky 1967). No more details have been provided regarding Denise's neurological status including her brain stem reflexes, and no EEG or other instrumental neurological examinations, if any were performed at all, have been reported.

The author tried to obtain a copy of the original report of the neurosurgeon. Surprisingly, neither the Heart of Cape Town Museum dedicated to the memory of the first heart transplant, ⁵ nor the University of Cape Town's Medical Library including its Manuscript and Archives Department's Chris Barnard Collection ⁶ possesses any examination report relating to Denise Darvall. Johan Brink, who was the Associate Professor and Clinical Director of Chris Barnard Division of Cardiothoracic Surgery at the University of Cape Town at the time of manuscript preparation, was not aware of the existence of such a document either. ⁷

The anonymous neurosurgeon who examined Denise was Peter Rose-Innes. His daughter, Olivia Rose-Innes, a journalist, has recently reported what her father had told her about the case. Per her account, the three criteria Peter Rose-Innes applied for diagnosis of brain death were:

“One: there had to be a background of injury likely to lead to brain death. Two: the patient had to be neurologically totally unreactive. Three: enough time needed to pass to be convinced that the patient was brain dead. There was considerable uncertainty about how long it should be, but I felt confirmation would need several hours,” Olivia quotes her father. (Rose-Innes 2009)

It is not clear what “neurologically totally unreactive” means, and more importantly, it is unclear whether these criteria were applied also to Denise. At least the fact that Denise's condition was characterized by prognosis (“lethal and beyond treatment”) instead of confirming the critical features (i.e., apnea and absence of brain stem reflexes) suggests that her status did not necessarily meet today's definition of brain death, as Wijdicks pointed out in the quote above about organ procurements before the Harvard Report (Wijdicks 2006).

One might object that the proper determination of brain death was not yet systematized in 1967; thus, the authors should not be expected to describe the key signs of brain death. However, as Giacomini points out in her paper exploring the historical background of the redefinition of death (Giacomini 1997), the Harvard Report in fact did not offer the first published criteria for brain death in 1968. Death definitions based on loss of brain function had been put forth by both transplantation and EEG specialists through the 1960s; even Pope Pius XII was requested to give his opinion on the issue in 1957 (Pope Pius 1958) and numerous international conferences were held on this topic before the first heart transplant. The best known of these was the Ciba Foundation symposium in 1966; the candid debate at this meeting reveals that the practices of defining criteria for brain death and procuring organs from brain-dead cadavers were well-established by the mid-1960s (Giacomini 1997). This fact was also confirmed by Barnard in his October 1968 lecture quoted above (Barnard 1969) (emphasis added):

We therefore felt that there was no objection to the use of a heart from a cadaver for this operation. Once cerebral death has been established by extensive neurological examination, the duty of the doctor towards this patient ends, and further treatment is of no avail. At the time when the first human heart transplantation was performed this was not a new concept, as for several years now neurosurgeons have been called upon to establish a point of cerebral death when further treatment would be discontinued.

It is therefore unlikely that apnea and lack of brain stem reflexes, if true, would not have been emphasized by Barnard's team upon publication of the operation.

The absence of spontaneous breathing is a sine qua non of brain death. Although Denise was “[d]eeply unconscious” and hypotonic on admission, she was certainly breathing spontaneously, since the suggested purpose of intubation was to keep the airways “scrupulously clean by suction” and to ventilate the patient with a respirator “at the first sign of respiratory failure” in order to assure the “adequate oxygenation of the tissues” (Bosman 1967). It has also been stressed that “[t]he pulse, respiration and blood pressure are checked and recorded 1/4-hly” (emphasis added), further supporting that the indication for intubation was not apnea, otherwise it would not have been necessary to track her respiratory rate, as it would have been set on the ventilator.

Since apnea is a necessary (but not sufficient) condition for brain death, Denise could not have been brain-dead on admission. However, her condition could have deteriorated and progressed to brain death while being on respirator, for example as a result of brain herniation (to be discussed later). Nevertheless, had she been brain-dead, she should have been apneic upon withdrawal of mechanical ventilation. This, however, has not been reported (Ozinsky 1967).

Donald McRae, a South Africa-born British journalist, who compiled four years of research and interviews of many of the then still-living in his documentary book about the first heart transplant, describes Denise's “labored breathing” after her ventilator was switched off (McRae 2007). Responding to the author's inquiry regarding this issue, McRae explained that this information had been conveyed to him in passing by one of the nurses who had been in the operating room.

I did not check it. It is quite possible I misunderstood her and my lack of scientific knowledge meant I did not ask her further questions. She said it in passing, thirty-five years after the event, so she might have been sloppy in her wording. ⁸

Misunderstanding by a lay journalist as well as sloppy wording or faulty memory of an eyewitness is, of course, possible. However, if Denise had been apneic, it is inexplicable why it has not been emphasized in the case report, given that Barnard was prepared for ethical and legal criticism (Brink and Cooper 2005). The absence of such a statement, similar to the missing description of brain stem reflexes, cannot be simply explained by the fact that the Harvard Report was not yet in existence, because, as shown above, the concept of brain death had been a matter of debate for years (Barnard 1969; Giacomini 1997; Machado 2005; Mollaret and Goulon 1959). Moreover, in the December 16, 1967, issue of the South African Medical Journal, which first reported on the successful heart transplantation in an editorial, a paper was also published on the medico-legal problem of death determination. In the article, the content of which was presented at a congress in July 1967, the British author discusses the significance of the irreversible damage to the brain and brain stem. He also raises the ethical problem of the apnea test:

Whether the brain stem centres are usefully ‘live’ can unfortunately be tested in only one way – by the withdrawal of artificial maintenance. This moment is the core of the moral problem, and it lies uncomfortably close to that of euthanasia. (Simpson 1967)

The ethical issues of apnea test (as well as its controversial scientific basis) remain debated today and cannot be overemphasized (Joffe 2020). Taken together, this evidence demonstrates that Barnard's team must have been aware of the importance of the presence or absence of brain stem reflexes and apnea in Denise's case.

The time course and circumstances of Denise's cardiac arrest following cessation of mechanical ventilation (to be discussed later) further supports that she was not apneic at the time of stopping artificial ventilation.

If brain death had occurred while Denise was on the respirator (for example as a result of brain herniation) she not only should have become apneic, but the autopsy should have proven the herniation. However, Denise's official post-mortem (Smith 1967) reports only markedly flattened convolutions but not brain herniation or any brain injury severe enough to necessarily have resulted in brain death. ⁹

Whether brain death and a negative autopsy are incompatible is debated. A study of patients clinically diagnosed as brain-dead revealed only mild histological brain changes at autopsy in a significant part of the cases. The authors of this study concluded that neuropathologic examination is not diagnostic of brain death (Wijdicks and Pfeifer 2008). According to other experts’ interpretation, however, the results question the validity of brain death criteria (Evans 2009; Potts 2009).

The histopathological results of Denise's autopsy have not been reported. Her additional injuries were reported as follows: linear skull fracture, extending from the right to the left parietal bone; small left subdural hemorrhage; contusion of the left temporal lobe with a central hematoma of 3 cm; blood-filled right lateral ventricle; multiple fractures of the right lower leg and pelvis with extensive pelvic retroperitoneal hemorrhage; bruising of the right buttock, right thigh, and both calves. The cause of death was “multiple injuries” (Smith 1967).

It is the interest of the recipient, and therefore the transplant surgeon, to declare the donor dead and take the organ as early as possible in order to avoid the ischemic injury of the graft. This is the reason why current worldwide legal regulation disqualifies transplant surgeons from confirming death of the donor, just as it was recommended by the Harvard Report as well. Barnard's team was not free from this conflict either, according to the first-hand experience of the above-mentioned Raymond Hoffenberg. Less than one month after the first heart transplant as the consultant on call, Hoffenberg was asked by the transplant team to pronounce a possible donor “dead” for Barnard's second heart transplant. Hoffenberg declined to do so because the patient still had a few elicitable neurological reflexes. Consequently, the transplant had to be postponed (finally performed on January 2, 1968) (Barnard 1968), leaving the transplant team deeply dismayed. “God, Bill, what sort of heart are you going to give us?” a professor of surgery (not Barnard, although he was also present) complained, as Hoffenberg (whose nickname was Bill) recalls the episode thirty-three years later (Hoffenberg 2001).

Peter Rose-Innes may have been under similar mental pressure when examining Denise, considering that performing the first heart transplant must have been at least as important as the second. Furthermore, Hoffenberg had the opportunity to freely refuse, as he had already been fired for political reasons when the incident occurred and was spending his very last shift at the Groote Schuur Hospital that night. [Even if Hoffenberg were relatively independent, he was seriously stressed by the incident and could not sleep that night, wondering whether he was “unnecessarily obstructive” (Hoffenberg 2001)]. Rose-Innes was likely more constrained and therefore his report about Denise's incurable brain damage cannot be regarded with certainty as independent. The tense atmosphere is well illustrated by Rose-Innes’ memoirs. His daughter, Olivia quotes her father's words as follows:

There was great pressure to hurry up! Chris marched up and down the passage outside, and kept peering in at us through the window in the door [of the high-care single bed room where Denise had been moved and where Chris's team was not let in]. It was stressful, but not too different to the typical stresses experienced by a neurosurgeon treating any serious head injury, which you deal with many times during your training and practice. (Rose-Innes 2009)

Did the Heart Stop Beating Spontaneously?

“2.20 a.m. Artificial ventilation of the donor ceased. 2.32 a.m. Cardiac arrest of the donor occurred, at which stage incision of the donor commenced,” according to the anesthetist Ozinsky's case report (Ozinsky 1967).

Thirty-two years later, in 1999, Chris Barnard recalled that night in an interview to BBC (BBC 1999): “When we were ready to remove the heart, I turned off the respirator and we waited an agonising 60 seconds until the heart stopped beating. I remember that clearly” (emphasis added). Barnard probably did remember right, as one can remember clearly, even thirty-two years later, the turning-point of one's life. The 60-s wait that Barnard mentioned (instead of the reported 12 min) may be surprisingly explained, rather than by Barnard's faulty memory, by the allegation published in McRae's book that the cessation of heartbeat had been due to an injection of potassium rather than a spontaneous event (McRae 2007); the 60-s wait may indicate the onset of the injection's effect.

According to McRae's narration based on Marius's statement, after switching off the ventilator and standing next to Denise waiting for her heart to stop, Marius proposed to take the still beating heart in order to prevent it from the hypoxemic damage caused by the long-lasting agonal phase of death. However, another member of the team, the senior surgeon O’Donovan, disagreed:

Stressing that their responsibility lay with the recipient rather than the brain-dead donor, Marius urged Chris to overrule O’Donovan and take the heart. If he needed it to stop beating, as conventional medical ethics dictated, they should inject it with potassium. And then they could take it and begin the transplant (…) Chris knew that Marius was right. He nodded his assent. Marius reached for the potassium while O’Donovan watched silently. It was a decision that they swore would always remain secret from the world outside. (McRae 2007)

The Barnard brothers kept the potassium injection in secret for almost four decades until Marius unfolded the story to McRae, several years after Christiaan's death. Surprisingly, however, he recanted his confession in his memoirs published in 2011 (Barnard and Simon 2011). This contradiction needs closer scrutiny.

In his autobiography, Marius did admit that he had made a statement regarding the potassium-induced heart arrest to McRae; however, as he claimed, it had been an untrue statement. His explanation for this false statement is hard, if at all possible, to understand and therefore, to believe:

I was aware of the book he [McRae] was writing, but our understanding was that the interview was not for that but for my biography. I’d had unpleasant experiences with the news media before, however, and had seen my words distorted, sensationalised and used without my permission. As a result, I’d learnt, whenever I gave information that was meant to be treated as confidential, to insert a single untruth which I would correct once my permission had been duly given. If this was then ever published, I would be able to trace the source. For this reason I told McRae that, during the first transplant, we had not waited until the donor heart had stopped beating before removing it, but used an injection of potassium to arrest it. This, of course, is contrary to what actually happened, which I described in the previous chapter and which Chris recounts in his first book: we waited until the heart had stopped beating – period. But McRae quoted me without asking, and so the untruth was published. (Barnard and Simon 2011)

Thus, Marius admits that he told McRae that Denise's heart had been stopped with potassium, but he claims he lied at the time. At this point the question arises, why he does not simply deny his testimony and instead fabricate this bizarre, illogical and incomprehensible explanation? As rebuttal, it is noteworthy that McRae did record their conversation (emphasis added):

‘I don’t give interviews,’ he [Marius] had bristled with pleasure when I [McRae] first called him, ‘and I’ve never told anyone out there the real story of me and Chris and the whole bloody transplant saga.’… I learned it was true that Marius had refused for years to grant an interview or to talk in public about his most personal feelings toward Chris – whom he admitted to loathing as much as loving. But believing that we were fated to work together, he decided to tell me “the whole damn story.” We settled down for a couple of weeks and spent day after day together, compiling one audiotape after another, as it all poured out of him. (McRae 2007)

It seems most likely that the story of potassium-induced heart arrest is true and Marius spoke confidentially to McRae about it, thinking that the conversation was being prepared for his own autobiography and that this part would not be published in the final edit. However, McRae wrote his own documentary and Marius was not a co-author on it, so he had no say in the content. Note that even McRae confirms that at the time of the interview “Marius was already planning his own autobiography” (McRae 2007). The last-but-one sentence of the above quote (“believing that we were fated to work together”) supports Marius's claim that his understanding with McRae – or perhaps misunderstanding – was that the interview was being prepared for Marius's own biography. [Ultimately, Marius's biography was prepared with the contribution of Simon Norval (Barnard and Simon 2011)].

It is important to emphasize that Marius repeatedly admitted and never denied that he had objected to waiting for Denise's heart to arrest spontaneously, as he confirmed it in his memoirs (Barnard and Simon 2011) and also in an interview to Newsweek published fifteen days after the first heart transplant (Giacomini 1997). This stable position of Marius further supports the likelihood of the potassium-induced cardiac arrest and tends to exclude the possibility that he made a false allegation actuated by jealousy towards Chris, shifting the responsibility onto his brother.

Furthermore, considering that Washkansky, the recipient was lying on the operating table in the adjacent theatre with an opened chest (Barnard 1967; Ozinsky 1967) and that a previous attempt to transplant a heart into him had been aborted, at least in part, due to overlong awaiting (Barnard and Simon 2011; Cooper 2017), it seems that due to Denise's predictably prolonged agony, Christiaan had no other choice than to agree with Marius and not to wait, but either to take Denise's beating heart or to stop her heart artificially.

The story of potassium-induced cardioplegia is widely accepted (Cole, Carlin and Carson 2015; DeSilva 2013) but still cannot be regarded as official. The above-mentioned Professor Johan Brink, who has been working at the Groote Schuur Hospital since 1984, refused this as “rumor” citing a claim Chris Barnard had made to him personally. ¹⁰ However, Barnard's statement cannot be regarded as independent and incontrovertible evidence. Nevertheless, it is important to note that, according to Brink, “for the second and all subsequent donors cerebral death was accepted as death of the donor and the heart was taken while still beating. Cardioplegia was introduced a few years later in our unit (around 1969)”. ¹¹

David Cooper, the British surgeon who worked with Barnard at Groote Schuur from 1980 until Barnard's early retirement in 1983, erroneously cites McRae in his historical book (Cooper 2017); therefore his reasoning is not relevant. According to Cooper, Marius told McRae that Denise's beating heart had been taken. Cooper argues that everyone in the operating room should have seen this, so it is impossible that the incident would not have been leaked. In reality, however, Marius stated that the heart was arrested with potassium injection, which could be done unobtrusively into an intravenous line. However, even Cooper could not make sense of Marius's explanation, admitting that “[t]o provide an author or journalist with incorrect information is certainly strange” (Cooper 2017).

According to Chris Barnard's paper, Denise's heart was removed when the electrocardiogram had shown no activity for five minutes of observation and there was absence of any spontaneous respiratory movements and absence of reflexes (Barnard 1967). Ozinsky's narration cited above appears to contradict this: “2.32 a.m. Cardiac arrest of the donor occurred, at which stage incision of the donor commenced” (Ozinsky 1967).

According to a historical paper by Brink and Cooper (Brink and Cooper 2005), Barnard invited a medical examiner into the operating room, who confirmed Denise's death. The presence of the medical examiner is not mentioned either in the original case reports published in the special edition of South African Medical Journal, in the documentary books by McRae (McRae 2007) and Cooper (Cooper 2017), or in Marius's memoirs (Barnard and Simon 2011); the examiner's report in not available either. ¹² Even if the medical examiner had been present in the operating room that Saturday night, it does not rule out the possibility that the donor received intravenous potassium, as it could have been administered out of view.

It would be reasonable to ask the participants about these details. To the best of the author's knowledge, the only living surgeon member of the team at the time of manuscript preparation was Professor Francois Hitchcock. However, he was working in the adjacent operating room that night where the recipient was operated, so he was unable to provide information in response to the author's query about what had happened or been said in the theatre of Denise Darvall. ¹³

Respiration and Heartbeat: Beating Without Breathing?

Ozinsky's aforementioned paper (Ozinsky 1967) raises the question whether it is realistic to believe that a brain-dead (and therefore apneic) patient's heart, without mechanical ventilation and any kind of life support, is able to beat for 12 min – and even longer. In other words, the prolonged agony after the ventilator was turned off provides further evidence that Denise was not brain-dead, as brain death would have resulted in apnea as well as serious hemodynamic and homeostatic misbalance, and thus cardiac arrest within a short time.

In a canine model in which six dogs were put into a state of brain death by elevating intracranial pressure with a balloon catheter, discontinuation of mechanical ventilation led to cardiac arrest within “a few minutes” (Shimada et al. 1994). In another study, six pigs pre-medicated with sedative and muscle relaxant agents were intubated and mechanically ventilated. After a stabilization period, the pigs were sacrificed by inducing hypoxic cardiac arrest via disconnecting them from the ventilator. The animals became pulseless 13 ± 3 min after cessation of ventilation (Van de Wauwer et al. 2009). Note that these animals were not brain-dead and were in stable hemodynamic condition when ventilation had been aborted; thus, their survival is expected to be longer compared to animals in the instable state of brain death.

A few human data are also available, especially from China, where the above-mentioned DBCD protocol is often used. In DBCD, it is necessary to wait for cardiac arrest of the brain-dead donors before organ removal begins. In a recent report of 199 such organ donors, the mean warm ischemia time (WIT), defined as the time elapsed from withdrawal of life support to cardiac arrest plus five minutes observation time plus the time to initiation of hypothermic perfusion of the graft was 16.2 ± 5.2 min (Sun et al. 2018). In another report of twenty-nine organ donors among whom only five donors met the criteria of brain death, WIT (defined as above but observation time was either two or five minutes) for all the twenty-nine donors (including those twenty-four who did not meet brain death criteria when life support was withdrawn) was 17.2 ± 4.4 min (Han et al. 2014).

Evaluation of Evidence

Taken together, the foregoing evidence suggest that a spontaneously breathing, unconscious, head-injured young woman was lying on the operating table as donor. Based on the available data, it is difficult to comment on the prognosis. The presumably not completely independent and therefore not completely unbiased declaration by Rose-Inn that Denise's injury was “lethal and beyond treatment” (Ozinsky 1967) is not supported by the case report and autopsy. As the much-publicized case of Zack Dunlap demonstrates, even full recovery can occur after a head injury apparently at least as serious as that Denise suffered (Nguyen and Zainer 2025). ¹⁴ However, regardless of what the prognosis may have looked like at the time and without doubting Barnard's sincere desire to help Whaskansky, applying cardioplegia to Denise in this tense situation, in the best possible light, is what one might call non-voluntary active euthanasia. [It is noteworthy that many years later, in 1980, Barnard published a book in defense of active euthanasia (Barnard 1980)]. Given that after 5 min of cardiac arrest (if this has taken place at all, as questioned above) one can potentially be resuscitated and therefore cannot be considered dead with certainty, the proximate cause of Denise’s death could potentially have been the organ removal itself.

Conclusion

Christiaan Barnard was a talented, ambitious, and hard-working doctor who established a cardiac surgery program on the African continent when heart surgery was still in its infancy. His cardiac surgery unit healed a great many of patients, including infants and children irrespectively of their race. It was the first heart transplant, however, that made him world-famous. The donor's neurological condition allegedly matched to what soon would be called “brain death.” This widespread public belief may have contributed greatly to the social acceptance of the concept of “brain death.” Thus, many think that the actual significance of the first human-to-human heart transplant was, more importantly than the surgical achievement, its influence on the re-evaluation of death and introduction of the concept of “brain death” into clinical practice (Altman 2001; Cooper 2017).

Data collected in this research suggest, however, that Denise Darvall, the first human heart donor, was not brain-dead when her mechanical ventilation was discontinued. Furthermore, there is significant evidence that her heart was arrested with potassium injection when spontaneous asystole had not occurred following ceasing ventilation. If both assumptions are true, it means that Denise's death resembles a non-voluntary active euthanasia. It would be an interesting thought experiment to imagine the history of the brain death concept and organ donation if the whole truth about the first heart transplant had been known to society.

Although the scenario described in this paper seems highly likely, it cannot be proven with absolute certainty based on the data presented here. It will be the task of future research to find new pieces of this puzzle – but not to sit in judgement on Barnard, as it belongs to one who searches the heart and tries the reins (Jeremiah 17:10), even the hearts of heart specialists. It is, however, incumbent on us, more so than to clarify the historical background, to ensure complete transparency of “cadaver” organ donation to society – including laypeople, healthcare providers, and church scholars – regarding the medical controversies as well as the metaphysical aspects of the procedure. This is essential for enabling all participants – donors or their next of kin, recipients, and healthcare providers – to make responsible decisions about their participation, considering not only the benefit of the recipient, but also the donor's human dignity and right to die a natural death. ¹⁵