Ticker: The Quest to Cre­ate an Ar­ti­fi­cial Heart by Mimi Swartz

The New York Review of Books - - Contents - Jerome Groop­man


The Quest to Cre­ate an Ar­ti­fi­cial Heart by Mimi Swartz. Crown, 317 pp., $27.00

Ar­ti­fi­cial Hearts:

The Al­lure and Am­biva­lence of a Con­tro­ver­sial Med­i­cal Tech­nol­ogy by Shel­ley McKel­lar.

Johns Hop­kins Univer­sity Press,

350 pp., $54.95

In the spring of 1974, my fifty-five-yearold fa­ther had a heart at­tack. He was rushed to a small com­mu­nity hospi­tal in Queens. I was liv­ing in Man­hat­tan, study­ing medicine at Columbia. By the time I ar­rived at the hospi­tal, he was in shock, gasp­ing for breath, his heart un­able to pump force­fully. The hospi­tal had no in­ten­sive care unit or car­di­ol­o­gist in at­ten­dance, no ef­fec­tive mea­sures to com­pen­sate for his dam­aged heart. He died be­fore my eyes.

Over the en­su­ing decades, although I am not a car­di­ol­o­gist, I’ve fol­lowed with in­ter­est the evolv­ing treat­ment of heart dis­ease. The in­ci­dence of fa­tal heart at­tacks has fallen dra­mat­i­cally since I lost my fa­ther. This is at­trib­ut­able in part to pre­ven­ta­tive mea­sures like quit­ting smok­ing, health­ier diet, ex­er­cise, and statin medicines, all of which re­duce the risk of ath­er­o­scle­ro­sis—the buildup of plaque in­side the ar­ter­ies. Treat­ment of heart at­tacks also has im­proved with the ad­vent of drugs that help dis­solve clots in blocked coro­nary ar­ter­ies. In ad­di­tion, tech­nol­ogy has ad­vanced to the point that dis­eased coro­nary ar­ter­ies can be me­chan­i­cally opened with an­gio­plasty and stents.

But with the im­proved sur­vival rate from a heart at­tack has come a strik­ing in­crease in the num­ber of peo­ple with con­ges­tive heart fail­ure. Dam­age to car­diac mus­cle may not be im­me­di­ately fa­tal, but over time the weak­ened heart strug­gles to pump blood ef­fec­tively. The cir­cu­la­tory sys­tem backs up, fill­ing the lungs with fluid and starv­ing the body of needed oxy­gen and nu­tri­ents. De­bil­ity and ul­ti­mately death en­sue. The great­est cost of con­ges­tive heart fail­ure, of course, is the suf­fer­ing and demise of pa­tients. But so­ci­ety as a whole also bears a sub­stan­tial eco­nomic bur­den: the direct and in­di­rect costs of care in the United States, in­clud­ing hos­pi­tal­iza­tion and med­i­ca­tions, have risen to about $31 bil­lion a year. This has spurred a search for more ef­fec­tive treat­ments.

The best op­tion for peo­ple with se­vere con­ges­tive heart fail­ure when med­i­ca­tions stop work­ing is a heart trans­plant. With cur­rent sur­gi­cal tech­niques and po­tent drugs to pre­vent re­jec­tion, trans­plan­ta­tion is of­ten suc­cess­ful. But there is a dearth of donors. So what is the al­ter­na­tive? Pa­tients look to de­vices to sus­tain them. This has been viewed as a straight­for­ward en­gi­neer­ing prob­lem with an en­gi­neer­ing so­lu­tion: the body’s nat­u­ral pump re­placed with an ar­ti­fi­cial one. But un­al­loyed suc­cess has largely proven elu­sive for nearly half a cen­tury.

A month af­ter my fa­ther died, I fin­ished my cour­ses in the class­room and be­gan my train­ing in the hospi­tal. That in­cluded scrub­bing in on open heart surgery, where I was ex­posed not only to tech­niques of by­pass­ing dis­eased coro­nary ar­ter­ies with grafts but also the ar­got of the sur­gi­cal res­i­dents. No­table was the term “cow­boy,” laud­ing a heart sur­geon (typ­i­cally a man at the time) who con­fronted the tough­est cases un­daunt­edly, scalpel al­ways in hand. But the ma­cho ap­pel­la­tion could have a mixed mean­ing, sug­gest­ing ag­gres­sive care be­yond what was rea­son­able and op­er­at­ing on dis­eased hearts in peo­ple too sick to sur­vive. The ra­tio­nal­iza­tion for those lost af­ter very high-risk op­er­a­tions was that “des­per­ate dis­eases re­quire des­per­ate reme­dies.”


Texas, was a cru­cible of mod­ern car­diac surgery, and the trope of cowboys and their ap­proach to care came to mind read­ing Mimi Swartz’s Ticker. An award-win­ning jour­nal­ist and the se­nior ex­ec­u­tive ed­i­tor of Texas Monthly, Swartz de­picts the quest to de­velop a suc­cess­ful ar­ti­fi­cial heart through a se­ries of por­traits of car­diac sur­geons:

These are physi­cians who have less in com­mon with your kind­hearted fam­ily doc­tor than with the first peo­ple who crossed Ever­est’s Khumbu Ice­fall or took the first steps on the moon. Med­i­cal ex­plor­ers, like all ex­plor­ers, tend to be bril­liant, ob­ses­sive, brave, and ar­ro­gant; many of them were and are ill-suited to so­ci­etal norms, crav­ing adu­la­tion while, at the same time, be­hav­ing in ways that don’t ex­actly build af­fec­tion. Maybe they have to be all those things: you don’t re­ally want the per­son who cuts into your heart to lack self-con­fi­dence.

The aim of some of these sur­geons, as Swartz puts it, is to cre­ate a de­vice that re­places “the heart as a near-per­pet­ual mo­tion ma­chine: it beats 60 to 80 times per minute, about 115,000 times a day, more than 2.5 bil­lion beats in an aver­age life­time .... The heart keeps pace con­tin­u­ously, whether a per­son is run­ning a marathon, mak­ing love, ar­gu­ing with a co­worker, or get­ting a good night’s sleep.” But a man-made “nearper­pet­ual mo­tion ma­chine” does not op­er­ate in a con­ducive en­vi­ron­ment: it must in­ter­act with the com­plex cur­rents and mul­ti­ple types of cells of our blood­stream. Blood clots of­ten de­velop in the pump, break off, travel to the brain, and cause strokes. Pre­vent­ing these clots from form­ing with blood­thin­ning an­ti­co­ag­u­lants can re­sult in mas­sive hem­or­rhage.

This re­al­ity, pre­dicted from stud­ies of pro­to­types us­ing an­i­mal sub­jects, did not de­ter sur­geons from at­tempt­ing to im­plant in hu­mans an ar­ti­fi­cial de­vice. In the 1960s two prom­i­nent car­diac sur­geons in Hous­ton, Michael DeBakey at Methodist Hospi­tal and Den­ton Coo­ley at St. Luke’s Epis­co­pal, raced to be the first to do so. In 1969 Coo­ley, who came from a wealthy and con­nected Texas fam­ily, was ac­cused by DeBakey, the son of Le­banese im­mi­grants, of steal­ing the de­sign for his ar­ti­fi­cial heart pump and im­plant­ing it reck­lessly. Coo­ley’s at­tempt failed (the pa­tient died within days), but his bold at­tempt made head­lines across the na­tion.

The quest in Hous­ton has con­tin­ued over the en­su­ing decades. Swartz’s main char­ac­ter, Dr. Os­car Howard Fra­zier—“known to all as Bud”—a trainee of both DeBakey and Coo­ley, has led the ef­fort at the Texas Heart In­sti­tute and its af­fil­i­ate St. Luke’s, now named Bay­lor St. Luke’s Med­i­cal Cen­ter. “Bud still had one goal to ac­com­plish be­fore he hung it up: he wanted to see

a work­ing ar­ti­fi­cial heart be­come a re­al­ity, a to­tal re­place­ment that could be im­planted and then for­got­ten,” Swartz writes. “Fi­nally,” in 2015, “Bud felt that he was close.” Fra­zier is de­scribed in glow­ing lan­guage:

At seventy, he had a leo­nine mane of shim­mer­ing white hair and the un­lined, lu­mi­nous skin that came from spend­ing the bet­ter part of fifty years in­doors at the hospi­tal . . . . Bud had also main­tained an au­then­tic West Texas drawl; he sounded to some like LBJ on Quaaludes. He lum­bered a lit­tle, some­times with a hitch in his step, the price of a high school foot­ball ca­reer in West Texas, along with years of stand­ing for hours in the op­er­at­ing room . . . . Most peo­ple on the street might have taken him for a col­lege his­tory pro­fes­sor emer­i­tus in­stead of a world-fa­mous car­diac sur­geon.

But Swartz be­lieves that be­hind the ve­neer of an ag­ing aca­demic is a heroic war­rior: “His life’s through line had be­come sav­ing the un­sav­able.” At times, she does stand back from these en­comi­ums and drops a cau­tion­ary note to the reader:

Bud Fra­zier likes to say that prac­tic­ing medicine sat­is­fies needs that are more meta­phys­i­cal, for both doc­tors and their pa­tients: “...Ev­ery prim­i­tive tribe has a Medicine Man,” mean­ing that in ev­ery era hu­man­ity wants to be­lieve in its heal­ers, who might be noth­ing more than sales­men with a good line.

In con­trast to Swartz’s nar­ra­tive told through the lives of fa­mous sur­geons, Shel­ley McKel­lar, a his­to­rian of medicine at the Univer­sity of Western On­tario, of­fers a de­tailed study of so­cial, cul­tural, and eco­nomic forces that pro­pelled a se­ries of “se­duc­tive de­vices”: ar­ti­fi­cial hearts that fell short of ex­pec­ta­tions. She sit­u­ates the early vi­sions of an ar­ti­fi­cial heart in

a pe­riod of great sci­en­tific and tech­no­log­i­cal op­ti­mism in Amer­ica, a time when the Con­gress en­dorsed many grand pro­jects, in­clud­ing land­ing a man on the moon. Con­vinced of the sci­en­tific com­mu­nity’s abil­ity to repli­cate heart func­tion me­chan­i­cally, Na­tional Heart In­sti­tute di­rec­tor Ralph Knutti pre­dicted the avail­abil­ity of ar­ti­fi­cial hearts for clin­i­cal use by Valen­tine’s Day 1970.

This over­promis­ing of sci­en­tific progress presages Nixon’s “war on can­cer,” which aimed for a cure to co­in­cide with Amer­ica’s bi­cen­ten­nial in 1976. McKel­lar poses pro­found clin­i­cal ques­tions that ex­tend be­yond the ar­ti­fi­cial heart: “When is med­i­cal tech­nol­ogy not the an­swer, par­tic­u­larly when it only ‘sort of’ works? When is it time to de­clare ‘No more!,’ and who gets to de­clare it?” She notes that for dif­fer­ent but re­lated rea­sons, the

“prom­ises” of many new tech­nolo­gies may cer­tainly have held more sway over the “pit­falls” for dy­ing pa­tients and their fam­i­lies, the de­vice in­dus­try, and de­ter­mined med­i­cal re­searchers. The char­ac­ter­i­za­tion of ar­ti­fi­cial hearts as a “half­way suc­cess,” as stated by one bioethi­cist in the 1980s, re­flected the many eco­nomic, so­cial, and mo­ral prob­lems as­so­ci­ated with the tech­nol­ogy. It chal­lenged the bi­nary char­ac­ter­i­za­tion of ther­a­peu­tics as ei­ther suc­cesses or fail­ures.

A “half­way suc­cess” oc­curred in 1982, not in Texas but in Utah, in the case of Bar­ney Clark, a re­tired Seat­tle den­tist with heart fail­ure. His clin­i­cal course was closely fol­lowed in the me­dia. Af­ter an ini­tial pos­i­tive

out­come, cel­e­brated in the press with pho­tos of a beam­ing Clark next to his wife, he suf­fered a cascade of de­bil­i­tat­ing and ul­ti­mately fa­tal side ef­fects, in­clud­ing gas­troin­testi­nal bleed­ing and mul­ti­ple strokes. “Politi­cians, med­i­cal pro­fes­sion­als, bioethi­cists, aca­demics, and in­dus­try peo­ple weighed in, lead­ing to in­creas­ing pub­lic dis­il­lu­sion­ment and vo­cif­er­ous de­bate over ar­ti­fi­cial heart tech­nol­ogy,” McKel­lar writes.

Most out­spo­ken against the clin­i­cal use of ar­ti­fi­cial hearts, bioethi­cists con­tested is­sues of in­formed con­sent and pa­tient au­ton­omy, ac­cess and cost, qual­ity of life and pa­tient self-de­ter­mi­na­tion, and the over­all cri­te­ria for suc­cess. A dis­cernible shift in med­i­cal and lay dis­cus­sions was ev­i­dent; once fo­cused pre­dom­i­nantly on the fea­si­bil­ity of de­vel­op­ing ar­ti­fi­cial hearts, they now ex­tended to the de­sir­abil­ity of such a clin­i­cally ac­cept­able de­vice (per­fected or oth­er­wise).

The re­spon­si­bil­ity of the hospi­tal’s In­sti­tu­tional Re­view Board (IRB), an over­sight com­mit­tee, came into tight fo­cus. As McKel­lar writes about the IRB in Utah:

Its mem­bers took se­ri­ously their du­ties as eth­i­cal med­i­cal pro­fes­sion­als . . . . They served as pro­tec­tor of the rights and safety of pa­tients and needed to up­hold the pro­fes­sional and eth­i­cal stand­ing of their in­sti­tu­tion. They also did not want to sti­fle in­no­va­tion at their hospi­tal, nor deny po­ten­tially life-sav­ing treat­ments to dy­ing pa­tients. The com­mit­tee mem­bers all agreed that a stricter pro­to­col needed to be worked out, most sig­nif­i­cantly a lim­it­ing of the po­ten­tial pa­tient pop­u­la­tion el­i­gi­ble for the ex­per­i­men­tal pro­ce­dure.

How pub­lic money should be spent in com­bat­ing heart dis­ease also be­came a flash­point. In 1988 the ar­ti­fi­cial

heart was called “the drac­ula of med­i­cal tech­nol­ogy” in a New York Times Op-Ed:

Dur­ing its 24-year life this Drac­ula of a pro­gram sucked $240 mil­lion out of the Na­tional Heart, Lung and Blood In­sti­tute. At long last, the in­sti­tute has found the re­solve to drive a stake through its vo­ra­cious cre­ation. “The hu­man body just couldn’t seem to tol­er­ate it,” ex­plains Claude Len­fant, the di­rec­tor of the in­sti­tute. Start­ing with Bar­ney Clark in 1982, ar­ti­fi­cial hearts have been im­planted in four coura­geous pa­tients in the United States and one abroad. Re­cip­i­ents would be­come such su­per­men, the tech­nol­ogy’s en­thu­si­asts had pre­dicted, that they’d have to be barred from marathon races. But the crude ma­chines, with their noisy pumps, sim­ply wore out the hu­man body and spirit. All pa­tients suf­fered life of poor qual­ity, of­ten punc­tu­ated by strokes or seizures .... The ar­ti­fi­cial heart project started at the same time as the Apollo pro­gram to land a man on the moon. Un­like Apollo, it veered badly off course.1 This un­signed Op-Ed ap­peared shortly af­ter Len­fant can­celed fed­eral fund­ing for de­vel­op­ment of the de­vice. Few peo­ple knew, McKel­lar notes, that he ac­tu­ally wrote it.

As Len­fant’s Op-Ed also noted, some “de­vices can be of tem­po­rary use in pa­tients wait­ing for a heart trans­plant”; prom­i­nent Amer­i­cans like Vice Pres­i­dent Dick Cheney have ben­e­fited from the HeartMate II, a sec­ond-gen­er­a­tion pump that as­sisted his left ven­tri­cle, to as­sure cir­cu­la­tion through­out his body, rather than re­place the whole heart. He lived with this im­planted left ven­tric­u­lar as­sist de­vice (LVAD) for twenty months be­fore un­der­go­ing a suc­cess­ful heart trans­plant op­er­a­tion in 2012, and cred­ited it with sav­ing his life.

This past May, af­ter the writ­ing of Swartz’s and McKel­lar’s books, the Hous­ton Chron­i­cle and ProPublica pub­lished a se­ries of in­ves­tiga­tive re­ports ques­tion­ing the pro­bity of the work of Bud Fra­zier, specif­i­cally how he se­lected pa­tients for surgery and the ve­rac­ity of his re­ports on ex­per­i­men­tal de­vices tested at Bay­lor St. Luke’s Med­i­cal Cen­ter.2 While the jour­nal­ists ac­knowl­edged that his achieve­ments have helped ex­tend the lives of “thou­sands of peo­ple world­wide each year,” they claimed that “out of pub­lic view, Fra­zier has been ac­cused of vi­o­lat­ing fed­eral re­search rules and skirt­ing eth­i­cal guidelines, putting his quest to make med­i­cal his­tory ahead of the needs of some pa­tients.” These se­ri­ous ac­cu­sa­tions were based on ex­am­i­na­tions of in­ter­nal hospi­tal re­ports, fed­eral court fil­ings, fi­nan­cial dis­clo­sures, and govern­ment doc­u­ments. “Fra­zier and his team im­planted ex­per­i­men­tal heart pumps in pa­tients who did not meet med­i­cal cri­te­ria to be in­cluded in clin­i­cal tri­als,” the Chron­i­cle noted. A sim­i­lar con­clu­sion had been made by an in­ter­nal hospi­tal in­ves­ti­ga­tion a decade ago but never pub­licly dis­closed. In fact, the hospi­tal went so far as to re­port these re­search vi­o­la­tions to the fed­eral govern­ment and was re­quired to re­pay mil­lions of dol­lars to Medi­care.

Dr. Frank Smart, a se­nior car­di­ol­o­gist who was at St. Luke’s be­tween 2003 and 2006, is quoted by the Chron­i­cle ad­mir­ing Fra­zier’s com­mit­ment to de­vel­op­ing life­sav­ing heart pumps, but be­lieves it led him to sur­gi­cally im­plant the de­vices into some pa­tients who were not yet sick enough to jus­tify what was, at the time, an ex­per­i­men­tal treat­ment. “In the old days of medicine... that’s the way these guys did things,” said Smart, rem­i­nisc­ing about Coo­ley’s first at­tempt. Now the chief of car­di­ol­ogy at Lou­i­si­ana State Univer­sity School of Medicine, Smart added, “It was, ‘Well, I have an idea, and I’m the one that knows best, and by golly, I’m go­ing to do it.’ And did that ad­vance the field? Maybe. Is it the right thing to do? Ab­so­lutely not.”

2Mike Hix­en­baugh (Hous­ton Chron­i­cle) and Charles Orn­stein (ProPublica), “Heart Fail­ure: A Hous­ton Sur­geon’s Hid­den His­tory of Re­search Vi­o­la­tions, Con­flicts of In­ter­est and Poor Out­comes,” Hous­ton Chron­i­cle, May 24, 2018. See also Orn­stein and Hix­en­baugh, “Sup­port­ers of a Famed Hous­ton Sur­geon Have Al­leged In­ac­cu­ra­cies in Our In­ves­ti­ga­tion. Here’s Our Re­sponse,” Hous­ton Chron­i­cle, June 29, 2018.

Other se­ri­ous charges against Fra­zier in­cluded his turn­ing down high-qual­ity donor hearts for pa­tients who had im­planted ex­per­i­men­tal de­vices. Smart said that Fra­zier was “more in­ter­ested in demon­strat­ing how well the de­vices per­formed over longer pe­ri­ods. Un­for­tu­nately, that meant that some peo­ple didn’t get trans­plan­ta­tion when that was prob­a­bly a bet­ter op­tion for them.” Dis­trust of Fra­zier was so ex­treme that Smart and other car­di­ol­o­gists re­sorted to “‘hid­ing pa­tients’—mov­ing them to other parts of the hospi­tal . . . buy­ing the pa­tients time to re­cover with less in­va­sive treat­ments or re­ceive a trans­plant in­stead.” Two other for­mer St. Luke’s doc­tors con­firmed to the re­porters this prac­tice of hid­ing pa­tients from Fra­zier. Fra­zier has re­but­ted these ac­cu­sa­tions; he de­nies im­plant­ing de­vices in pa­tients who did not need them and as­serts that pa­tients who re­quired trans­plants re­ceived them when donor hearts be­came avail­able. But at the time, ex­ec­u­tives at the hospi­tal clearly were deeply dis­turbed by what was hap­pen­ing, the Chron­i­cle notes. The ex­ec­u­tives

con­tem­plated which sce­nario would be worse for the hospi­tal’s bot­tom line and rep­u­ta­tion: cut­ting ties with Texas Heart, the famed re­search or­ga­ni­za­tion founded 46 years ear­lier by Coo­ley, or con­tin­u­ing to be as­so­ci­ated with the in­sti­tute should the pub­lic ever learn about its re­search vi­o­la­tions. “Should the af­fil­i­a­tion be dis­solved, the im­pact to St. Luke’s mar­ket po­si­tion is un­clear,” ex­ec­u­tives wrote, ac­cord­ing to a sum­mary re­port. “It is likely that such news would gen­er­ate na­tional at­ten­tion and neg­a­tively im­pact our stand­ing in the US News & World Re­port rank­ings.”

Based on the Chron­i­cle’s in­ves­ti­ga­tion, it seems that Fra­zier’s sur­gi­cal out­comes were among the worst in the coun­try: “From 2010–15, about half of the tra­di­tional Medi­care pa­tients who re­ceived an im­plantable heart as­sist de­vice from Fra­zier died within a year, nearly dou­ble the na­tional mor­tal­ity rate for such pa­tients.” The St. Luke’s and Texas Heart ex­ec­u­tives, ac­cord­ing to the ex­posé, “took lit­tle or no ac­tion to rein in a doc­tor whose work con­tin­ues to earn the hospi­tal in­ter­na­tional ac­claim.” In June, Medi­care an­nounced it was cut­ting off all pay­ments to the hospi­tal’s heart trans­plant pro­gram.

Fra­zier claimed his sur­gi­cal out­comes were worse be­cause his pa­tients were sicker and at higher risk than those treated at other hospi­tals. His sup­port­ers con­tend that his life has been one of ser­vice to such pa­tients. They as­serted to the Chron­i­cle that “many in Hous­ton and across the coun­try . . . would not be alive if not for Fra­zier’s will­ing­ness to take the most dif­fi­cult cases.” His vin­di­ca­tion, some of these de­fend­ers claim, was the 2010 FDA ap­proval of a “con­tin­u­ous-flow LVAD” for heart fail­ure. “If he broke rules . . . it was to give dy­ing peo­ple a shot at sur­vival, a mis­sion that con­sumed his life,” one said.

For nearly forty years, I’ve con­ducted clin­i­cal tri­als of ex­per­i­men­tal ther­a­pies—not de­vices, but drugs. These stud­ies largely in­volved pa­tients with ad­vanced can­cer or AIDS, des­per­ate dis­eases for which, at times, des­per­ate reme­dies were given. It was ag­o­niz­ing to tell some pa­tients that they were judged too ill to re­ceive the ex­per­i­men­tal treat­ment.

The temp­ta­tion to break the trial’s rules, to imag­ine one­self as a heroic war­rior and treat pa­tients any­way, is a pow­er­ful one. The more I felt its pull, the more I came to ap­pre­ci­ate that third-party over­sight is es­sen­tial when con­sid­er­ing de­vi­a­tion from a pro­to­col. A clin­i­cal in­ves­ti­ga­tor can ap­peal to the IRB and the drug maker for ex­emp­tions so as to in­clude pa­tients who do not fall within the in­clu­sion cri­te­ria of the trial. Doc­tors can also pe­ti­tion the FDA for per­mis­sion to treat one pa­tient in­di­vid­u­ally, en­tirely off pro­to­col. We need such guardrails to pro­tect pa­tients not only from ex­treme risks from ex­per­i­men­tal ther­a­pies to the qual­ity and longevity of their lives but also from dis­torted judg­ment re­sult­ing from a doc­tor’s mixed emo­tions of com­pas­sion and am­bi­tion.

Last year, the FDA, Health Canada, and the Eu­ro­pean Union all ap­proved the SynCar­dia ar­ti­fi­cial heart. It re­quires the pa­tient to be teth­ered at all times, writes McKel­lar, to a “clunky” ex­ter­nal pneu­matic ap­pa­ra­tus with care­tak­ers in at­ten­dance 24/7, hardly the de­vice that Fra­zier and oth­ers en­vi­sioned that is self-con­tained and can be “im­planted and then for­got­ten.” For those whose left ven­tri­cle lacks suf­fi­cient muscular force, thereby starv­ing tis­sues of oxy­gen-rich blood, LVADs have been in­cre­men­tally im­proved. In April of this year, The New Eng­land Jour­nal of Medicine pub­lished two-year out­comes com­par­ing an LVAD that uses cen­trifu­gal flow with one that uses ax­ial flow in heart fail­ure pa­tients. Although the for­mer, which was cham­pi­oned by Fra­zier and his team, showed some­what bet­ter per­for­mance with re­spect to pump mal­func­tion and clot­ting, there was still the same risk of dis­abling stroke, gas­troin­testi­nal bleed­ing, and death. An ac­com­pa­ny­ing ed­i­to­rial con­cluded that “even with this next-gen­er­a­tion [cen­trifu­gal flow] de­vice . . . com­pli­ca­tions oc­cur at an un­ac­cept­ably high fre­quency, and there re­mains a press­ing need for ad­di­tional im­prove­ments in...tech­nol­ogy.”3 That press­ing need must be tightly yoked to strict eth­i­cal stan­dards in hu­man ex­per­i­men­ta­tion.

3Man­deep R. Mehra, Daniel J. Gold­stein, Nir Uriel, et al., “Two-Year Out­comes with a Mag­net­i­cally Le­vi­tated Car­diac Pump in Heart Fail­ure,” and Mark H. Drazner, “A New Left Ven­tric­u­lar As­sist De­vice—Bet­ter, but Still Not Ideal,” The New Eng­land Jour­nal of Medicine, Vol. 378, No. 15 (April 12, 2018).

A pa­tient’s fam­ily feel­ing the beat of an ar­ti­fi­cial heart af­ter surgery at Hu­mana Hospi­tal-Audubon, Louisville, Ken­tucky, 1984

Leonardo da Vinci: The Heart (de­tail), circa 1512–1513

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