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Implantation of Total Artificial Heart in Congenital Heart Disease

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Left Axis Deviation in Children Without Previously Known Heart Disease.

Andrew E Schneider¹, Bryan C Cannon¹, Jonathan N Johnson¹

¹Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine.

|February 14, 2018

Summary

Left axis deviation (LAD) in children is uncommon. Further cardiac workup is recommended if LAD is accompanied by ECG chamber enlargement, a QRS axis ≤-42°, or abnormal physical exam findings.

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Area of Science:

Pediatric Cardiology
Electrocardiography
Diagnostic Imaging

Background:

Left axis deviation (LAD) on electrocardiogram (ECG) is rare in children.
LAD can be associated with underlying heart disease (HD).
Optimal diagnostic strategies for asymptomatic children with LAD are unclear.

Purpose of the Study:

To identify predictors of heart disease in children with LAD.
To stratify risk for further cardiovascular investigation in pediatric patients with LAD.

Main Methods:

Retrospective chart review of patients aged 1-17 years with LAD (QRS axis 0 to -90).
Exclusion of patients with pre-existing heart disease.
Analysis of echocardiogram findings and clinical data.

Main Results:

296 pediatric patients with LAD were identified.
15% of patients who underwent echocardiography had heart disease.
Patients with HD were more likely to have a QRS axis ≤-42°, ECG chamber enlargement/hypertrophy, and abnormal cardiac exam findings.

Conclusions:

Isolated LAD in asymptomatic children may not require further investigation.
Echocardiography is indicated for LAD in conjunction with ECG chamber enlargement, QRS axis ≤-42°, or abnormal physical exam findings.