Left Axis Deviation

Cardiac axis represents the sum of depolarisation vectors generated by individual cardiac myocytes. Clinically is is reflected by the ventricular axis, and interpretation relies on determining the relationship between the QRS axis and limb leads of the ECG (below diagram) Since the left ventricle makes up most of the heart muscle under normal circumstances, normal cardiac axis is directed downward and slightly to the left: Normal Axis = QRS axis between -30° and +90°. Abnormal axis deviation, indicating underlying pathology, is demonstrated by: ...

Left Axis Deviation LAD Left Axis Deviation = QRS axis less than -30°. Normal Axis = QRS axis between -30° and +90° Right Axis Deviation = QRS axis greater than +90° Extreme Axis Deviation = QRS axis between -90° and 180° (AKA “Northwest Axis”) Hexaxial Reference System Hexaxial Reference System – relationship between QRS axis and frontal leads of the ECG. How to recognise left axis deviation Three Lead analysis QRS is POSITIVE (dominant R wave) in Lead I QRS is NEGATIVE (dominant S wave) in leads II, III and aVF ...

Learning cardiac axis interpretation can be tedious. I have created an open source webapp hosted on CardiacAxis.com. Here you will be able to analyse in English and German the ECG variations with axis deviation. The Axis trainer online is interactive and the arrow can be moved to demonstrate each of the specific QRS complex changes. Bookmark to your phone homepage and try it out for yourself. Below is a quick demonstration through 360 degrees… ...

↪ ECG Basics Homepage Who is SAM? As a routine part of ECG analysis, we need to determine the ECG AXIS. It isn’t really enough to just whimper… “Is it normal?” So, to help understand axis a tiny bit…I need to introduce you to SAM – the Super Axis Man Building SAM – the Super Axis Man (1) Draw a circle and put SAMs head on the top. Note: SAM is smiling today because he is learning something… ...