Internal Mammary Artery Ligation — the Angina Cure Fake Surgery Matched in 1959

Summary

In 1957 surgeon J. Roderick Kitchell and colleagues at Presbyterian Hospital in Philadelphia, following an Italian lead, began tying off the internal mammary arteries in the chests of angina patients and reporting that roughly two-thirds felt better — and the gap between that reported relief and the operation's actual physiological effect is the entire case, because the operation did almost nothing the body could measure. The procedure was supposed to relieve the crushing chest pain of coronary disease by occluding the internal mammary arteries so that blood would be diverted into the heart muscle. It was simple, it was fast, it was performed under local anaesthetic, and within two or three years it had been carried out on thousands of patients across Italy and the United States on the strength of uncontrolled before-and-after testimonials.

The reported numbers looked persuasive: in the largest case series, on the order of two-thirds to three-quarters of patients said their angina improved, many dramatically, with effects holding up over months and years of follow-up. What no one had done was ask whether the cut, rather than the ligature, was doing the work. Angina is a subjective, fluctuating symptom, and the act of being operated on by a confident surgeon is among the most powerful placebos in medicine.

The reckoning was unusually clean and unusually fast. Between 1959 and 1960 two small randomized trials — Leonard A. Cobb's group at the University of Washington and E. Grey Dimond's at the University of Kansas — did something no surgical evaluation had done before: they randomized angina patients to either the real ligation or a sham operation, an identical skin incision in which the arteries were exposed but left intact, with neither the patient nor the assessing physician knowing which had been done. The sham patients improved exactly as much as the ligated ones. The exercise electrocardiograms were unchanged by either operation. The benefit was real to the patients and entirely placebo in origin.

The operation was abandoned almost immediately — not banned by any agency, not litigated, but disproven and quietly dropped. Its lasting legacy is the opposite of its intended one: internal mammary artery ligation is now the founding textbook example of why surgery, like a drug, must be tested against a placebo, and of how a self-limiting subjective symptom plus an enthusiastic operator can manufacture thousands of "cures" out of nothing but expectation and a scar.

Timeline

1939

Fieschi proposes the concept

Italian surgeon Davide Fieschi reasons that ligating the internal mammary arteries will force blood into the coronary circulation via collateral vessels, and reportedly tries it on a single patient. The idea lies largely dormant for fifteen years.

1954

Battezzati revives and popularizes it

Surgeon Mario Battezzati and colleagues at the University of Parma begin performing bilateral internal mammary artery ligation for angina, building a large case series and reporting striking symptomatic improvement.

1957

The operation crosses to America

Stimulated by the Italian reports, J. Roderick Kitchell, Robert P. Glover and colleagues at Presbyterian Hospital, Philadelphia, begin ligating internal mammary arteries in U.S. angina patients under local anaesthesia.

1958

Enthusiastic series published

Kitchell, Glover and co-workers report that roughly two-thirds to three-quarters of their patients experienced subjective improvement, and the simple office-grade operation spreads rapidly. Reader's Digest and the lay press amplify it as a breakthrough.

1959

Battezzati's large series appears

Battezzati and colleagues report results on some 304 cardiac patients, with the great majority improved and most sustaining the benefit on follow-up — uncontrolled, but widely cited as validation.

28 May 1959

Cobb's double-blind trial lands

Leonard A. Cobb, G. I. Thomas, D. H. Dillard, K. A. Merendino and R. A. Bruce publish in the New England Journal of Medicine the first sham-controlled surgical trial: 17 patients randomized to real ligation (8) or sham incision (9), double-blind. Both groups improve; the exercise ECG is unchanged.

1959

A second uncontrolled series raises doubts

Independent clinical evaluations begin questioning whether the operation does anything physiological, noting the implausibility of the proposed collateral mechanism.

1960

Dimond confirms the verdict

E. Grey Dimond, C. Frederick Kittle and James E. Crockett publish in the American Journal of Cardiology a parallel sham-controlled trial (18 patients): improvement in the sham group is identical to the ligated group; the exercise electrocardiogram is unaltered by either.

1960–1961

The operation collapses

With two blinded trials in agreement, internal mammary artery ligation for angina is effectively abandoned across U.S. and European centers within roughly a year of the second paper.

1961

Henry Beecher canonizes it

Anaesthesiologist Henry K. Beecher cites the ligation trials in JAMA as evidence of "the powerful placebo" in surgery, fixing the case in the literature as a methodological landmark.

2010s

Re-litigated by ORBITA

The ligation precedent is invoked repeatedly when the 2017 ORBITA trial finds that coronary stenting for stable angina performs no better than a sham procedure — half a century later, the same lesson, the same surprise.

A Mechanism on Paper and a Symptom That Lied

The operation was built on a plausible-sounding physiological story and a symptom that could not be trusted. Fieschi's hypothesis — that occluding the internal mammary arteries would back-pressure blood into the diseased coronary bed through collateral channels — was anatomically speculative and was never demonstrated to move meaningful blood into ischemic myocardium. What made the idea survive was not vascular evidence but the nature of angina itself. Angina pectoris is a subjective, episodic symptom whose frequency and severity wax and wane with mood, weather, activity and attention; it is exquisitely responsive to suggestion and to the natural regression that follows any acute flare. A patient who has consented to chest surgery, been opened under the hands of a confident specialist, and told the arteries were tied off is primed to report less pain — and to behave in ways that produce less pain. Battezzati's and Kitchell's case series captured exactly that effect and mistook it for revascularization. With no control group, "improvement" measured the patient's expectation and the surgeon's enthusiasm, not the blood supply to the heart.

Industrial Spread on Testimonial Evidence

The ligation operation scaled because it was cheap, quick, and apparently safe. Performed through small incisions under local anaesthesia, it required no heart-lung machine and no thoracotomy, so a wide range of surgeons could offer it, and a wide range of cardiac patients could be persuaded to accept it. The reported response rates — roughly two-thirds to three-quarters improved — were the kind of numbers that, in an era before randomized surgical trials existed, looked like proof. The lay press treated it as a frontier cure for one of the most feared conditions of mid-century medicine, and demand followed the publicity. Thousands of operations were performed across Italy and the United States before anyone had established that the ligature did anything the incision alone did not. The procedure had achieved its surrogate endpoint — patients said they felt better — while the true endpoint, objective evidence of improved coronary perfusion or exercise tolerance, had never been tested and, it would turn out, never existed.

The Sham Incision That Ended It

What stopped internal mammary artery ligation was a methodological innovation as much as a result. Cobb and his colleagues at the University of Washington recognized that the only way to separate the operation's effect from the operation's theatre was to perform the theatre on a control group: an identical skin incision, the arteries dissected free and exposed, but left untied, with the patient and the evaluating physician kept blind to which procedure had been done. When they published in the New England Journal of Medicine on 28 May 1959, the verdict was stark. Among 17 patients, the 9 who received only the sham incision reported as much relief as the 8 who were actually ligated; nitroglycerin use fell in both; and the exercise electrocardiogram — an objective measure that cannot be talked into improving — was unchanged by either operation. Dimond, Kittle and Crockett at Kansas reached the same conclusion in 1960 with a parallel 18-patient trial. The two studies together, fewer than 40 patients, retired an operation that had been performed on thousands. There was no recall and no tribunal; the evidence simply removed the rationale, and surgeons stopped offering it. Henry Beecher folded it into his 1961 account of "the powerful placebo," and the operation passed from cure to cautionary tale within about three years of its American debut.

Contributing Factors

01

A subjective endpoint mistaken for a physiological cure

Success was defined as the patient reporting less angina — a symptom that fluctuates, regresses to the mean, and bends to suggestion — rather than as any measured improvement in cardiac function. Optimizing a self-reported outcome in a placebo-sensitive condition guarantees an apparent benefit whether or not the intervention does anything. The metric rewarded the operator and flattered the operation while the heart was untouched.

02

A plausible mechanism substituting for evidence of effect

The collateral-flow rationale sounded physiological and was never shown to deliver meaningful blood to ischemic muscle. A mechanistic story that could be true was treated as proof that the operation was working. Plausibility is not efficacy; an intervention can have an elegant theory and zero physical effect.

03

Uncontrolled before-and-after series presented as proof

Battezzati's and Kitchell's testimonial case series — large, enthusiastic, and uncontrolled — became the evidence base by default because no controlled surgical evaluation tradition existed. Before-and-after data in a fluctuating, suggestible condition cannot distinguish treatment from placebo, regression, or natural history, yet they were read as validation and drove mass adoption.

04

Low friction enabled mass exposure before testing

Because the operation was fast, cheap, performed under local anaesthesia, and required no specialized cardiac infrastructure, thousands of patients were exposed to it within a few years of its introduction. Ease of delivery accelerated diffusion ahead of evidence; a harder, costlier procedure would have spread slowly enough for scrutiny to catch up.

05

The absence — until 1959 — of any norm of testing surgery against placebo

No one had ever subjected an operation to a blinded sham control, so a procedure could become standard on uncontrolled enthusiasm alone. The field had no built-in mechanism to ask whether the cut, not the cure, was responsible. The harm here was modest and the fix fast precisely because two investigators invented the missing control; the lasting damage was the principle's prior absence.

Aftermath

The material consequence was thousands of unnecessary chest operations performed on cardiac patients for a benefit that was entirely placebo — a comparatively contained harm, since the procedure was low-risk and the symptom relief, however illusory in mechanism, was real to those who felt it. The durable ripple is methodological and enormous. Internal mammary artery ligation became the canonical demonstration that surgery is as susceptible to the placebo effect as any pill, and that invasive procedures must, where ethical, be evaluated against sham controls. Henry Beecher's 1961 framing of "the powerful placebo" rests heavily on these trials, and they are taught today as the origin of sham-controlled surgical research. The lesson had to be relearned in public when the 2017 ORBITA trial found coronary stenting for stable angina no better than a sham — and commentators reached straight back to the 1959 ligation study to explain why no one should have been surprised. The operation that was meant to reroute blood to the heart instead rerouted the entire discipline toward the placebo control, and "internal mammary artery ligation" became the byword for the cure that worked only because the patient believed it had.

Lessons

Test the cut, not just the cure. When an intervention is invasive and its target outcome is subjective, the act of intervening is itself a powerful treatment. If you cannot tell whether the procedure or the theatre produced the benefit, you have not measured efficacy — build a sham control before you scale.
Distrust improvement in a symptom that fluctuates and obeys suggestion. Pain, fatigue, mood, and angina regress to the mean and respond to expectation. Before-and-after gains in such measures are the easiest thing in medicine to manufacture and the hardest to attribute. Demand an objective endpoint that cannot be talked into changing.
A plausible mechanism is a hypothesis, not a result. An elegant physiological story explaining why something should work is a reason to test it, never a substitute for testing it. Ask for evidence that the proposed mechanism actually moves the physical quantity it claims to.
Watch the case series that has no control. Uncontrolled enthusiasm — large, confident, testimonial — is how an ineffective intervention reaches thousands before anyone asks the disconfirming question. Treat an impressive before-and-after series as an unanswered question, not an answer.
Re-run the placebo question whenever the field forgets it. The same surprise recurred with stenting in 2017 because the discipline had let the lesson lapse. When a popular invasive procedure has never been compared to a sham, the absence of that comparison is the finding — go get it.