Medical Article: DeMizio v. JHH 3

The Appellate Court of Maryland filed an unreported opinion on May 8, 2026. It ruled on procedural and evidentiary issues in a medical malpractice case. The case was Deidre DeMizio, et al. v. Johns Hopkins Health System Corp., et al. (No. 2412, September Term, 2023). It arose from an underlying medical malpractice and wrongful death action. The plaintiffs filed this case in the Circuit Court for Montgomery County following a cardiac arrest death. That was after an undiagnosed cardiac amyloidosis of a dentist. Following a multiple week trial the jury returned a defense verdict. It found that none of the providers breached the standard of care, the plaintiffs appealed on several evidentiary grounds. This is Part 3 of this Baltimore Medical Malpractice Lawyer Blog series. It focuses on the exclusion of a medical article in a medical malpractice case. It also addresses temporal boundaries governing standard-of-care evidence.

In Part 1, I looked at the trial court’s refusal to reopen a discovery window. Also, Part 2 involved the court’s restriction of expert testimony regarding non-FDA-approved pharmaceuticals under the Daubert-Rochkind framework.

Factual Background on Medical Article in Medical Malpractice

The core liability dispute in the underlying lawsuit focused on whether the defendants failed to properly and timely diagnose the decedent’s cardiac amyloidosis. The relevant period of medical evaluation and care provided by the defendants spanned from February 2015 until the patient’s sudden cardiac death on December 15, 2017.

At trial, the parties disputed what diagnostic criteria and clinical guidelines governed a reasonably competent cardiologist’s knowledge and actions during that specific 2015–2017 timeframe. The plaintiffs sought to introduce into evidence a specific medical article published by the Cleveland Clinic. This article updated guidelines for cardiac amyloidosis. It mapped out advanced clinical paths to identify the disease before fatal cardiac events occurred.

The journal published the Cleveland Clinic article in December 2017—the exact month and year of the decedent’s death. The journal released it at the very tail end of the relevant treatment. Thus, it was not available to the medical community during the nearly three years of prior evaluations that formed the basis of the negligence claims. Furthermore, the plaintiffs’ legal team failed to identify, produce, or otherwise disclose this specific literature during the discovery period. They waited until the middle of the trial to attempt to introduce it. They were trying to bolster the live testimony of their expert witnesses cardiologist. The defendants immediately opposed its admission, causing an extensive sidebar and a formal evidence ruling by the trial judge.

Parties’ Arguments

At trial and on appeal, the plaintiffs said that the trial court committed error. It completely kept out the Cleveland Clinic article. They argued that the literature was not being offered to introduce a new, after death method. Rather, to support and confirm the existing diagnosis techniques that their expert witness was already stating to the jury.

The article was published in December 2017. The plaintiffs maintained it was strictly at the same time as the final month of the decedent’s life. It accurately showed the peak of medical knowledge at the exact moment his care finished. The plaintiffs further argued that the defendants could suffer no genuine prejudice or unfair surprise from the text. The Cleveland Clinic is a famous institution. Its published diagnosis thresholds should be familiar to any board-certified cardiologist’s conduct in a court of law.

The defendants argued that the trial court’s decision to bar the article was a proper and necessary application of Maryland evidence law. They said that the standard of care must be measured by the knowledge available to a practitioner at the time of the alleged negligent acts, not through the lens of retrospective literature.

The defendants pointed out that the article was published in December 2017. It could not possibly have informed or guided a physician’s clinical decisions in 2015, 2016, or the vast majority of 2017. Introducing a post-dated or contemporaneous diagnostic guideline, they argued, would unfairly invite the jury to judge the defendants’ past actions using subsequent medical consensus. Finally, the defendants raised a clear procedural objection. They emphasized that the plaintiffs’ failure to disclose the article during the formal discovery window denied the defense an opportunity to review the text with their own experts. This constituted an incurable trial-by-ambush tactic.

Court’s Ruling on Medical Article in Medical Malpractice

The Appellate Court of Maryland reviewed the trial judge’s exclusion of the medical article. It used an abuse of discretion standard for the procedural discovery violation. It used a de novo standard for the underlying legal relevance regarding the standard of care. The appellate court affirmed the trial court’s ruling on both grounds, finding no error or abuse of discretion.

First, the court addressed the temporal relevance of the literature. The appellate court reiterated a foundational tenet of Maryland tort law. The medical standard of care is strictly measured by the clinical information, diagnostic tools, and scientific consensus available to a practitioner at the exact time the alleged negligent act or omission occurred.

The Cleveland Clinic article was published in December 2017. It was physically impossible for it to have informed, influenced, or guided the defendants’ diagnostic actions during the preceding years of the patient’s treatment. The court noted that a physician cannot be held liable for failing to adhere to a diagnostic guideline that had not yet been written, compiled, or disseminated to the wider medical community.

Second, the court affirmed the exclusion based on the plaintiffs’ clear procedural default. By failing to disclose the Cleveland Clinic article during the active discovery phase, the plaintiffs violated the structural requirements designed to prevent surprise at trial.

Finally, the appellate court observed that even if the exclusion had been technically improper, it constituted entirely harmless error. The trial record revealed that the plaintiffs’ expert cardiologist was still fully permitted to testify at length regarding the underlying diagnostic criteria. This was based entirely on his personal clinical knowledge and active practice. Thus, the physical absence of the document did not prevent the plaintiffs from presenting their core theory of liability to the jury.

Commentary by Baltimore Medical Malpractice Lawyer Mark Kopec on Medical Article in Medical Malpractice

The Appellate Court of Maryland’s decision to uphold the exclusion of the Cleveland Clinic article was predicable based on its date. It sounds like the plaintiffs were able to get the substance equivalent into evidence through the expert’s testimony. That’s probably the best they can do given that the release date of the article was after almost all of the treatment already had occurred.

The procedural basis for the exclusion also was problematic for the plaintiffs. Disclosing the article for the first time during the plaintiffs’ expert’s trial testimony was not going to go well. Even though the expert had said in deposition that he was not relying on any medical articles, the plaintiffs still had a fair chance at using it if they had disclosed it before the expert had taken the stand.. Even if disclosure was the day before the expert testified, a judge could find that the defense could adequately consult with their experts and prepare cross examination.

You can read additional Blog posts on the topics of Expert Testimony and Discovery.

Stay tuned for Part Four of this series. I will examine the final issue raised on appeal. The total exclusion of a fact witness and the strict rules governing the legal relevance of non-party patient outcomes.

Mark Kopec is a top-rated Baltimore medical malpractice lawyer. Contact us at 800-604-0704 to speak directly with Attorney Kopec in a free consultation. The Kopec Law Firm is in Baltimore and helps clients throughout Maryland and Washington, D.C. Thank you for reading the Baltimore Medical Malpractice Lawyer Blog.