<P> In electrocardiography, left axis deviation (LAD) is a condition wherein the mean electrical axis of ventricular contraction of the heart lies in a frontal plane direction between − 30 ° and − 90 ° . This is reflected by a QRS complex positive in lead I and negative in leads aVF and II . </P> <P> Common causes of LAD include left ventricular hypertrophy (LVH), left anterior fascicular block (or hemiblock) and inferior myocardial infarction . Less commonly LAD may be a normal variant, particularly in obese or stocky individuals, or it may be associated with Wolff--Parkinson--White syndrome or an ostium primum atrial septal defect . </P>

What is the meaning of left axis deviation in ecg