Few diagnoses carry the same medicolegal weight as the missed myocardial infarction (MI). Despite guideline-driven chest pain pathways and high-sensitivity troponins, missed MI remains among the most common – and most costly – sources of litigation against emergency departments.

The reasons go beyond clinical error. Increasingly, these cases hinge on systemic and administrative failures: lack of serial EKGs, incomplete handoffs, or protocols that prioritize throughput metrics over observation time. A 2023 JAMA Network Open study found that nearly 4% of patients discharged from the ED with chest pain had a major adverse cardiac event within 30 days, and in half of those cases, documentation showed incomplete application of the HEART or EDACS score.

The legal arguments follow a familiar pattern: Was the physician negligent, or was the system unsafe? Attorneys increasingly pursue corporate negligence claims, arguing that hospitals failed to create a culture or infrastructure that ensured safe cardiac evaluation—such as inadequate staffing, broken EHR alerts, or absent 24-hour cardiology coverage.

One illustrative 2024 case in California (Doe v. Valley Health System) centered not on the emergency physician’s decision, but on the hospital’s failure to mandate serial troponin testing intervals, despite published protocols. The case settled for $3.5 million.

From an expert witness standpoint, key review points include:

• Were risk stratification tools properly applied and documented? 
• Was there appropriate physician supervision of mid-level providers? 
• Did system policies align with AHA/ACC Chest Pain Guidelines (2021) and ACEP Clinical Policy (2023)? 
• Were EKGs repeated when symptoms evolved or persisted? 

Ultimately, the “missed MI” case is less about clinical judgment and more about the interface between medicine, policy, and accountability. In many EDs, that gap remains wide enough to drive litigation through.

References

1. Pope JH et al. “Missed diagnoses of acute cardiac ischemia in the emergency department.” N Engl J Med. 2000;342:1163-1170. 
2. Sandoval Y et al. “High-sensitivity cardiac troponin in the evaluation of possible acute myocardial infarction.” JAMA Netw Open. 2023;6(8):e2330213. 
3. American Heart Association. “2021 AHA/ACC Guideline for the Evaluation and Diagnosis of Chest Pain.” Circulation. 2021;144(22):e368–e454.