## Facts

- Haskell Karp, age 47, had a long history of severe cardiovascular disease and was treated in Houston in 1969 by Dr. Denton A. Cooley, with Dr. Domingo S. Liotta involved in the artificial heart work.
- Cooley proposed a staged surgical plan: (1) repair a left-ventricular aneurysm by ventriculoplasty (wedge excision), (2) if unsuccessful, implant a totally mechanical heart as a temporary measure, and (3) perform a human heart transplant when a donor heart became available.
- The wedge excision was performed on April 4, 1969 and failed; a totally mechanical heart was then implanted and maintained circulation for about 64 hours.
- A donor heart became available; a transplant was performed April 7, 1969. Karp died on April 8, 1969, roughly 32 hours after the transplant.
- The family signed a written surgical consent referencing the mechanical heart and significant risks; plaintiffs claimed disclosures about the device’s experimental character and testing limitations were inadequate and that the procedure amounted to using Karp as a human experimental subject.
- Plaintiffs also alleged fraud and negligence in the performance of the operations and challenged several trial evidentiary rulings.
- Defense evidence emphasized Karp’s grave underlying condition and the failed initial operation, with expert testimony that death was likely regardless; the artificial heart was identified, at most, as a less likely contributing factor.
- In federal diversity litigation applying Texas law, the district court directed a verdict for defendants at the close of plaintiffs’ evidence; plaintiffs appealed.

## Issues

1. Whether plaintiffs presented sufficient expert evidence under Texas law to submit to a jury claims that defendants breached the medical standard of care in the wedge excision, mechanical-heart implantation, or transplant.
2. Whether plaintiffs produced adequate proof of lack of informed consent, including expert evidence of the professional disclosure standard and proof that any nondisclosure caused injury.
3. Whether the record supported jury submission of fraud or misrepresentation based on alleged assurances or incomplete disclosure about the device and procedure.
4. Whether characterizing the procedure as “human experimentation” altered the liability analysis or supplied a basis for negligence absent standard malpractice proof.
5. Whether challenged evidentiary rulings and alleged trial-management errors required reversal.

## Decision

- The Fifth Circuit affirmed the directed verdict for defendants.
- The court held plaintiffs failed to provide required expert testimony establishing the applicable standard of care, breach, and medical causation for malpractice theories.
- The court held informed-consent claims failed for lack of expert proof of the professional disclosure standard, lack of proof of breach, and lack of non-speculative causation.
- The court held alleged optimistic statements about the procedure did not amount to actionable fraud on the evidentiary record.
- The court rejected the “human experimentation” theory as an independent route to liability because plaintiffs did not show the intervention was non-therapeutic or outside acceptable medical judgment.
- The court found no reversible abuse of discretion in the challenged evidentiary rulings or in trial management.

## Legal Principles

- In a Texas medical-malpractice case, the plaintiff generally must prove the standard of care, breach, and causation through competent expert medical testimony; only rare “obvious” cases avoid that requirement.
- Under the then-applied Texas approach to informed consent, the scope of required disclosure is measured by professional practice; expert testimony is ordinarily necessary to establish what a reasonable physician would disclose and whether the defendant fell short.
- Informed-consent liability requires proof of causation, including evidence that adequate disclosure would have altered the patient’s decision and that the nondisclosure is linked to the injury.
- Innovative or experimental treatment is evaluated within ordinary negligence/malpractice frameworks; novelty does not itself establish negligence without proof the conduct fell outside reasonable medical judgment and caused harm.
- Fraud in the medical setting requires evidence of material misrepresentation, reliance, and causation; expressions of medical opinion or prognosis, without proof of intentional deception, are insufficient to reach a jury.

## Conclusion

The Fifth Circuit upheld judgment for the surgeons because plaintiffs did not produce expert evidence sufficient to create jury issues on malpractice, informed consent, fraud, experimentation-based negligence, or causation, and the trial court’s evidentiary and procedural rulings did not warrant reversal.


Karp v. Cooley, 493 F.2d 408 (5th Cir. 1974)