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Acute myocardial infarction and left bundle branch block with changing axis deviation.

Salvatore Patanè, Filippo Marte, Giuseppe Dattilo

International Journal of Cardiology

|May 8, 2009

Summary

This study presents a rare case of left bundle branch block with changing axis deviation in an elderly patient experiencing acute myocardial infarction. The findings suggest a potential coexistence of left posterior hemiblock and predivisional left bundle branch block.

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Area of Science:

Cardiology
Electrophysiology
Medical Diagnostics

Background:

Changing axis deviation is observed in various cardiac conditions, including atrial fibrillation, atrial flutter, and acute myocardial infarction.
Left bundle branch block (LBBB) typically presents with normal or left axis deviation on electrocardiograms (ECGs).

Observation:

This case report details a rare instance of LBBB exhibiting changing QRS morphology and axis deviation.
The patient was a 93-year-old Italian woman admitted with acute myocardial infarction.

Findings:

The intermittent shift in the QRS axis in the presence of complete LBBB suggests complex underlying electrical conduction abnormalities.
The most plausible explanation identified is the coexistence of left posterior hemiblock and predivisional left bundle branch block.

Implications:

Understanding these rare ECG presentations is crucial for accurate diagnosis and management of complex cardiac events.
This case highlights the importance of considering combined conduction defects in patients with LBBB and dynamic ECG changes.