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Three Part Question

In [patients presenting to the ED with cardiac-sounding chest pain] what is the [sensitivity] of the [initial 12 lead ECG]?

Clinical Scenario

A 55-year-old man with cardiac-sounding chest pain presents to the emergency department. The first ECG is normal. Just before you discharge him you stop to wonder what the sensitivity of the initial 12 lead ECG is in predicting acute myocardial infarction.

Search Strategy

Medline 1966-09/00 using the OVID interface.
[(exp myocardial infarction OR myocardial infarction.mp OR AMI.mp OR MI.mp) AND (exp electrocardiography OR electrocardiogram.mp OR ECG.mp OR EKG.mp) AND (initial.mp OR first.mp OR single.mp or premier.mp)] AND maximally sensitive diagnostic study filter LIMIT to human and english.

Search Outcome

543 papers were found, out of which 533 were irrelevant or of insufficient quality. The remaining 10 papers are shown below.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Mc Guiness JB et al, 1976, Scotland	898 patients admitted to CCU. 400 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	51%
Starck ME and Vacek JL, 1987, USA	221 ED chest pain patients. 39 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	62%	Air force hospital, possible selection bias No raw cardiac enzyme data confirming how AMI was diagnosed
Sharkey SW et al, 1988, USA	34 patients admitted to CCU. 34 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	61%	CCU population not ED Small population size
Rouan GW, et al, 1989, USA	918 ED chest pain patients. 811 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	13%	Interrator agreement of ECG interpretation not measured from separate participating ED Inclusion of AMI and ischaemic ECG changes
Fesmire FM et al, 1989, USA	440 ED chest pain patients. 100 with AMI.	Prospective diagnostic cohort.	Sensitivity of initial ECG	47%	No evidence of timing of the initial ECG
Gibler WB et al, 1992, USA	616 ED chest pain patients. 108 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	36%	Recruitment criteria unclear Unclear if series or selection of patients recruited
Zalenski RJ et al, 1993, USA	149 ED chest pain patients. 34 with AMI.	Prospective diagnostic cohort.	Sensitivity of initial ECG	47.1%	Small population
Young GP and Green TR, 1993, USA	222 ED chest pain patients. 43 with AMI.	Retrospective survey	Sensitivity of initial ECG	28%	Retrospective study Study population mostly elderly
Kudenchuk PJ et al, 1998, USA	3027 ED chest pain patients. 1149 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	69%	Initial ECG taken by paramedics, not in ED
Fesmire FM, 1998, USA	1000 ED chest pain patients. 204 with AMI.	Prospective diagnostic cohort	Sensitivity of initial ECG	55.4%	?34 patients had AMI following admission to ED

Comment(s)

At presentation history, clinical findings and ECG are all that are available to aid clinicians in the diagnosis of AMI. These studies have shown that the first ECG is between 13-69% sensitive for AMI.

Clinical Bottom Line

The first ECG is not sensitive enough to rule out AMI in the Emergency Department.

References

1. Mc Guiness JB, Begg TB, Semple T. First Electrocardiogram in recent Myocardial Infarction. BMJ 1976;2(6033):449-51.
2. Starck ME and Vacek JL. The Initial Electrocardiogram During Admission for Myocardial Infarction. Use as a predictor of clinical course and facility utilization. Arch Intern Med 1987;147(5):843-6.
3. Sharkey SW, Apple FS, Elsperger KJ, et al. Early peak of creatine kinase MB in acute myocardial infarction with a nondiagnostic electrocardiogram. American Heart Journal 1988;116(5):1207-11.
4. Rouan GW, Lee TH, Cook EF et al. Clinical Characteristics and Outcome of Acute Myocardial Infarction in Patients with Initially normal or Non-specific Electrocardiograms. Am J Cardiol 1989;64(18):1087-92.
5. Fesmire FM, Percy RF, Wears RL, et al. Initial ECG in Q wave and Non-Q wave Myocardial Infarction. Ann Emerg Med 1989;18(7):741-6.
6. Gibler WB, Young GP, Hedges JR, et al. Acute Myocardial Infarction in Chest Pain Patients with Non-diagnostic ECGs: Serial CK-MB Sampling in the Emergency Department. Ann Emerg Med 1992;21(5):504-12.
7. Zalenski RJ, Cooke D, Rydman R, et al. Assessing the Diagnostic Value of an ECG Containing Leads V4r, V8 and V9: The 15 lead ECG. Ann Emerg Med 1993;22(5):786-93.
8. Young GP and Green TR. The role of Single ECG, Creatinine Kinase and CKMB in diagnosing patients with acute chest pain. AJEM 1993;11(5):444-9.
9. Kudenchuk PJ, Maynard C, Cobb LA, et al. Utility of the Prehospital Electrocardiogram in Diagnosing Acute Coronary Syndromes: The Myocardial Infarction Triage and Intervention (MITI) Project. J Am Coll Cardiol 1998;32(1):17-27.
10. Fesmire FM, Percy RF, Bardoner, JB et al. Usefulness of Automated Serial 12-Lead ECG Monitoring During the Initial Emergency Department Evaluation of Patients With Chest Pain. Ann Emerg Med 1998;3(1):3-11.