QRS axis: Difference between revisions
→How do you determine the electrical heartaxis
| Line 31: | Line 31: | ||
<flashow>http://nl.ecgpedia.org/images/b/bc/Normal_SR_vector.swf|height=300px</flashow> | <flashow>http://nl.ecgpedia.org/images/b/bc/Normal_SR_vector.swf|height=300px</flashow> | ||
When you average all electrical signals from the heart, you can indicate the direction of the average electrical depolarization with an arrow (vector). This is the heartaxis. Especially a change of the heartaxis or an extreme deviation can be an indication for pathology. | When you average all electrical signals from the heart, you can indicate the direction of the average electrical depolarization with an arrow (vector). This is the heartaxis. Especially a change of the heartaxis or an extreme deviation can be an indication for pathology. | ||
* | *Positive (the average of the QRS surface above the baseline) QRS deflection in lead I: the electrical activity is directed to the left (of the patient) | ||
* | *Positive QRS deflection in lead AVF: the electrical activity is directed down. | ||
This indicates a normal heartaxis. Usually, these two leads are enough to diagnose a normal heartaxis! | This indicates a normal heartaxis. Usually, these two leads are enough to diagnose a normal heartaxis! | ||