114
edits
Technical Problems: Difference between revisions
no edit summary
No edit summary |
No edit summary |
||
| Line 7: | Line 7: | ||
==Lead reversals== | ==Lead reversals== | ||
Lead switches are a common mistake when ECGs are made and can lead to wrong diagnoses. Common mistakes are: | Lead switches are a common mistake when ECGs are made and can lead to wrong diagnoses. Common mistakes are: | ||
* '''Left-right arm reversals''' | * '''Left-right arm reversals''' lead to a negative complex in lead I with a negative P wave in lead I. They are one of the most common causes of right axis deviation on the ECG! | ||
* '''Arm-foot switches''' lead to a very small or 'far field' signal in leads II or III. | * '''Arm-foot switches''' lead to a very small or 'far field' signal in leads II or III. | ||
* '''Chest lead reversals''' lead to inappropriate R wave progression (increase - decrease - increase) and are often easily recognized. | * '''Chest lead reversals''' lead to inappropriate R wave progression (increase- decrease-increase) and are often easily recognized. | ||
Therefore '''any right axis or small signal in an extremity lead''' should be reason enough to check lead positioning. A previous ECG can be very helpful. | Therefore '''any right axis or small signal in an extremity lead''' should be reason enough to check lead positioning. A previous ECG can be very helpful. | ||
<div style="float:right"> | <div style="float:right"> | ||