Overview

Patients presenting with significant new-onset ST elevation on their ECG in the setting of acute myocardial infarction are considered candidates for emergent reperfusion therapy. Four ECG patterns observed in acute myocardial infarction, in which ST elevation is absent, are now also considered an indication for emergent reperfusion therapy. The four ‘STEMI equivalent’ ECG patterns are, 1) left bundle branch block satisfying the Smith modified Sgarbossa criteria, 2) acute posterior myocardial infarction 3) hyperacute T wave change and 4) the presence of de Winter T waves on the ECG. Although not STEMI equivalent, a fifth ECG pattern is associated with imminent coronary artery occlusion (Wellens syndrome) and mandates early intervention. On completing this course, the practitioner will identify STEMI equivalent ECG patterns and the ECG changes associated with Wellens Syndrome.

Faculty

Planner and Author: Dr John Seery MB PhD

• Consultant Physician at St. Vincent's University Hospital, Dublin, Ireland
• Lecturer at the School of Medicine and Medical Science, University College Dublin, Ireland
• Studied medicine at the University of Cambridge, United Kingdom
• A Natural Sciences graduate of Trinity College Dublin, Ireland
• PhD in Cell Biology from University College London, United Kingdom

Planner: Dr Karen Strahan PhD (University of Cambridge), Head of Editorial

Planner: Tommy O'Sullivan, CME Manager

Estimated Time to Complete

2.0 hours

Target Audience

Select Target Audience(s)

- Physicians

- Nurses

- Nurse Practitioners

- Physician Assistants

- Paramedics

Learning Objectives

Upon successful completion of this activity, you will be able to:

• Explain the historical origin of ‘STEMI criteria’
• Explain the term ‘STEMI equivalent ECG pattern’
• Explain the clinical significance of STEMI equivalent patterns on the ECG of patients presenting with suspected acute myocardial infarction
• Apply and interpret the Smith modified Sgarbossa criteria in cases of suspected acute myocardial infarction presenting with left bundle branch block on their ECG
• Identify the ECG changes characteristic of posterior myocardial infarction
• Identify hyperacute T wave change on the ECG of patients presenting with suspected acute myocardial infarction
• Identify de Winter T waves on the ECG of patients presenting with suspected acute myocardial infarction
• Identify and interpret the ECG findings associated with Wellens syndrome
• Distinguish normal variant prominent T waves from hyperacute T waves in patients presenting with chest pain

Course Content

• Introduction
• Before we begin Key terms explained
• Posterior Myocardial Infarction ECG Findings
• Identifying Left Bundle Branch Block on the ECG
• Smith modified Sgarbossa Criteria
• The Smith modified Sgarbossa Criteria Case Study
• The Chest Leads Normal Findings
• Identification of Hyperacute T Waves on the ECG
• Prominent T Waves in Healthy Adults
• de Winter T Waves
• Wellens Syndrome ECG Findings
• Quiz
• Quiz Explanation - Q1/Q2
• Quiz Explanation - Q3
• Quiz Explanation - Q4/Q5

Release date

30-JUL-2026

Expiration date

30-JUL-2029

Instructions for Participation

Participants must complete the online activity during the valid period as noted above.

Follow these steps:

1. View videos in sequence
2. Read the papers on the Essential Reading List
3. Complete quiz
4. View and complete post quiz videos to support learning outcomes and objectives
5. Complete the activity evaluation form to provide feedback for continuing education purposes and for the development of future activities
6. Download the Certificate of Completion

Relevant Financial Disclosures

Planners and faculty for this activity have no relevant financial relationships with commercial interests to disclose.

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