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Updated: Jan 27, 2026
05:26
Postconditioning with Lactate-enriched Blood for Cardioprotection in ST-segment Elevation Myocardial Infarction
Published on: May 28, 2019
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Left bundle branch block as equivalent of ST-segment elevation myocardial infarction: when yes, when not?
Laura Ceballos-Naranjo1, Jonathan Cardona-Vélez2
1Facultad de Medicina, Universidad Pontificia Bolivariana, Medellín, Colombia.
Archivos De Cardiologia De Mexico
|April 2, 2019
Summary
New left bundle branch block with ischemic symptoms is often treated like a heart attack. However, current diagnostic criteria are not optimal, and this review examines their limitations and benefits.
Area of Science:
- Cardiology
- Medical Diagnostics
- Electrocardiography
Background:
- New left bundle branch block (LBBB) with ischemic symptoms is traditionally viewed as an electrocardiographic equivalent of ST-elevation myocardial infarction (STEMI).
- Emergent reperfusion therapy is typically indicated for patients presenting with these findings.
- Optimal diagnostic criteria for identifying STEMI equivalents in LBBB remain elusive.
Purpose of the Study:
- To review and detail the proposed electrocardiographic criteria for diagnosing STEMI equivalents in the presence of new or presumed new left bundle branch block.
- To analyze the limitations and diagnostic yield of existing criteria.
- To highlight the advantages and potential benefits of these criteria.
Main Methods:
- Literature review of proposed diagnostic criteria for LBBB as a STEMI equivalent.
- Analysis of the strengths and weaknesses of each criterion.
- Discussion of the clinical implications and diagnostic challenges.
Main Results:
- Several criteria have been proposed to define LBBB as a STEMI equivalent.
- None of the current criteria have achieved optimal diagnostic accuracy.
- Each criterion presents specific problems and limitations in clinical application.
Conclusions:
- The definition of LBBB as a STEMI equivalent requires further refinement.
- Ongoing research aims to improve diagnostic yield and clinical decision-making.
- Better criteria are needed for timely and appropriate reperfusion therapy in these patients.
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