axis deviation (left)
Last reviewed 01/2018
In this condition there is a swing of the cardiac axis to the left - ie less than minus 30 degrees. It is usually the result of a left anterior hemiblock rather than to the increased bulk of muscle of the left ventricle. Other causes include:
- inferior myocardial infarction
- ventricular pre-excitation
- hyperkalaemia
- tricuspid atresia
- ostium primum atrial septal defect
- artificial cardiac pacing
ECG findings: the QRS becomes predominantly negative in III and positive in aVL. The condition is not significant until the QRS is also predominantly negative in II.