Value of extreme left axis deviation in patients with complete left bundle branch block
Guido Vannoni1, Carlos D Labadet1, Giuliana Caminotti1
1División Cardiología, Hospital General de Agudos Dr. Cosme Argerich, Pi y Margal 750, 2nd floor, (1155) Ciudad Autómona de Buenos Aires, Argentina.
Current Problems in Cardiology
|September 12, 2025
Summary
In patients with left bundle branch block (LBBB), a leftward QRS axis deviation (LAD) indicates worse systolic function and ventricular remodeling. This finding highlights LAD as a significant marker for identifying high-risk cardiovascular patients.
Area of Science:
- Cardiology
- Cardiac Electrophysiology
- Cardiovascular Imaging
Background:
- Complete left bundle branch block (LBBB) is linked to increased cardiovascular event risk.
- The prognostic significance of extreme leftward QRS axis deviation (LAD) in LBBB remains debated.
Purpose of the Study:
- To determine if LAD (-45°) in LBBB patients serves as a marker for systolic dysfunction.
- To assess if LAD in LBBB patients is associated with ventricular remodeling.
Main Methods:
- A cross-sectional cohort study included 102 patients diagnosed with LBBB.
- Echocardiography was performed to evaluate left ventricular (LV) dimensions, wall thickness, and ejection fraction (EF).
Main Results:
- Patients with LAD exhibited significantly lower EF (32.2% vs. 46.7%) and increased LV end-diastolic diameter index.
- LAD demonstrated 45% sensitivity and 88% specificity for identifying reduced EF.
- Cardiomyopathy was more prevalent in the LAD group (93.1% vs. 61.6%), with a higher incidence of eccentric LV hypertrophy.
Conclusions:
- In LBBB, LAD (-45°) is associated with impaired systolic function and dilated left ventricles.
- LAD identifies patients with LBBB who have a higher likelihood of cardiomyopathy and eccentric hypertrophy.
Keywords:
Left axis deviationLeft bundle-branch blockLeft ventricle remodelingLeft ventricular functionMore Related Videos
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