High Risk Emergency Medicine: Legal Disasters in ACS

Annual High Risk Emergency Medicine: Legal Disasters in ACS

  • Presented by Amal Mattu, MD, FAAEM, FACEP
    • Professor and Vice Chair
    • Co-Director, Emergency Cardiology Fellowship
    • Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, Maryland

Why We Miss ACS?

  • Focus on subtleties to better protect patients and yourself.

Non-STE ACS

  • ACC/AHA 2007 Guidelines for the Management of Patients with Unstable Angina/Non-STEMI
    • Summary of literature and recommendations for management of non-STE ACS

Rules of Cardiology

  • Rule #1: You cannot diagnose every case of acute coronary syndrome.
  • Rule #2: You can't change rule #1.

Importance of ACS Diagnosis

  • ACS is high-risk but has a high payoff.
    • Potential for very good outcomes versus very bad outcomes.
  • Missed ACS can lead to significant legal consequences.

Medical Malpractice and ACS

  • Missed ACS accounts for 20% of malpractice dollars paid out in Emergency Medicine.
  • Majority of cases involve failure to recognize concerning features in the history.
  • 25-50% of cases involve ECG misreads.

Pitfalls in ACS Diagnosis: The History

  • Failure to do and document a good history, especially the History of Present Illness (HPI).
  • Importance of a thorough HPI:
    • Using mnemonics like OPQRST (Onset, Provoking factors, Quality, Radiation, Severity, Timing).
    • Asking about onset, precipitating factors, quality, radiation, severity, and timing of chest pain.
  • OLDCAAAR HPI for patients with Chest Pain (CP):
    • Onset, Location, Duration, Character, Alleviating/aggravating factors, Activity at onset, Associated Symptoms, Radiation.
  • Caveats:
    • Understanding that not everything asked/done is documented.
    • HPI is only one component of any Assessment, Diagnosis, and Plan (ADP).
    • Good documentation of a good history might keep you out of trouble.

Common Misdiagnosis: Reflux

  • Most common misdiagnosis of ACS is reflux.
  • Up to 50% of MI patients have an increase in belching.
  • 20% describe their ACS pain as "burning" or "indigestion."
  • 15% of ACS patients get improvement with antacids.
  • 8% of patients report their ACS pain began during a meal.
  • GERD and ACS frequently co-exist.

Failure to Appreciate ACS in Young Patients

  • ACS is typically reported in individuals > 55 years old.
  • Young patients:
    • 123,000 Acute Myocardial Infarctions (AMIs) per year in patients aged 29-44 years.
    • 5-10% of AMIs occur in patients < 45 years old.
    • A minority are related to cocaine use.
  • Autopsy studies (Korean/Vietnam wars):
    • Joseph, et al (J Am Coll Cardiol, 1993): Autopsy study of 111 patients (< 35yo, avg. age 26yo), victims of non-cardiac trauma.
      • Evidence of atherosclerosis in 78%.
      • 20% had LAD or “significant” 2- and 3-vessel involvement.
      • 9% had > 75% narrowing in at least one vessel.
  • Marsan, et al (Acad Emerg Med, 2005):
    • 1023 patients aged 24-39yo presenting with CP (cocaine users excluded).
    • 98% available for 30-day follow-up.
      • 5.4% ruled in for ACS.
      • 2.2% had an adverse cardiac event (death, MI, need for PCI or CABG).
  • Important Point: Don’t discount the risk of ACS purely because of a patient’s age!
  • Pediatricians wrote children in the U.S. at least 2.8 million prescriptions for drugs to lower cholesterol; nearly 2.3 million of them were for statins. (ConsumerReports.org, June 2010)

Failure to Appreciate ACS and Atypical Presentations in Women

  • Multiple studies and scientific statements highlight the importance of recognizing ACS in women (CJC 2014, JACC 2015, Circulation 2016, Heart 2016, Eur Heart J: Acute Cardiovasc Care 2016, J Am Heart Assoc 2017, Am J Cardiol 2017, Heart 2017, Eur Heart J: Acute Cardio Care 2017, Clinical Cardiology 2019, European Heart Journal 2020, Heart 2020, Crit Pathways in Cardiol 2021, Circulation 2021).
  • ACS in Women:
    • Painless presentations are more common.
    • Atypical locations of pain and radiation.
    • Unexplained dyspnea, flu-like symptoms, indigestion, malaise, fatigue, weakness.
      • More symptoms than men lead to misdiagnosis.
    • These points apply to younger women as well as older women.
  • McSweeney, Circulation 2003:
    • Unusual prodromal symptoms:
      • Chest discomfort 30% (only!).
      • Dyspnea 42%.
      • Sleep disturbance 48%.
      • Fatigue 71%.

Upper Abdominal Pain

  • If there’s no significant tenderness, consider the possibility of ACS (or another thoracic problem).

Over-Reliance on Troponin Negative (TNs)

  • Diagnosis of ACS requires 3 components:
    • A good history.
    • Scrutiny of the ECG.
    • Troponins (TNs) – But not just troponins alone!
  • EVERY validated ADP incorporates all 3 components (History, ECG, Troponins).

Pitfalls in ACS Diagnosis: The ECG

  • 25-50% of cases involve ECG misreads; personal experience suggests > 50% involve ECG misreads that are not “arguable.”
  • Over-reliance on the computer interpretation, especially “normal” and “non-specific” readings.
  • Lack of scrutiny of the ECG and premature closure due to atypical presentation.
    • Especially in young patients and women.
  • Ignoring the ECG because of negative Troponins.
  • Failure to repeat the ECG:
    • If the first ECG is poor quality.
    • If ongoing concerning symptoms.
    • ACC/AHA guidelines recommend serial ECGs every 15-30 minutes for the first hour if there are concerning symptoms and the initial ECG is non-diagnostic.
    • 15-20% of STEMIs are diagnosed on the repeat ECG!

Take-Home Points: The History

  • Do and document a good history.
  • Do not exclude ACS purely based on:
    • Reflux symptoms.
    • Age.
    • Female gender.
    • Abdominal pain.
    • Negative Troponins.

Take-Home Points: The ECG

  • Scrutinize the ECG.
  • Don’t trust the computer interpretation.
  • Get serial ECGs when the history is concerning but the first ECG is non-diagnostic.