Left axis deviation

Some of the causes include normal variation, thickened left ventricle, conduction defects, inferior wall myocardial infarction, pre-excitation syndrome, ventricular ectopic rhythms, congenital heart disease, high potassium levels, emphysema, mechanical shift, and paced rhythm.

[3] Determining the electrical axis can provide insight into underlying disease states and help steer the differential diagnosis.

These include normal variation, left ventricular hypertrophy, conduction defects, inferior wall myocardial infarction, preexcitation syndrome, ventricular ectopic rhythms, congenital heart disease, hyperkalemia, emphysema, mechanical shift and pacemaker-generated paced rhythm.

Mechanical shifts that cause LAD are expiration or raised diaphragm from pregnancy, ascites (fluid accumulation in the abdomen), abdominal tumor, or enlarged liver or spleen.

[5] For example, if left ventricular hypertrophy is the cause of LAD, symptoms can include shortness of breath, fatigue, chest pain (especially with exercise), palpitations, dizziness, or fainting.

If high blood pressure is the cause of LVH, then treatment is targeted at lowering blood pressure and preventing further enlargement of the left ventricle by using medications such as angiotensin-converting enzyme inhibitors (ACE inhibitors), angiotensin receptor blockers (ARBs), calcium channel blockers, diuretics, and beta-blockers.