Basics: Difference between revisions
→Technical problems with the ECG
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#Leads V7-V8-V9 can be used to diagnose a posteriorinfarct. It is means that after V6, leads are pkaced towards the back. See the chapter[[Ischemia]] for other ways of diagnosing posterior infarction. | #Leads V7-V8-V9 can be used to diagnose a posteriorinfarct. It is means that after V6, leads are pkaced towards the back. See the chapter[[Ischemia]] for other ways of diagnosing posterior infarction. | ||
=Technical problems | =Technical problems= | ||
==Lead reversals== | ==Lead reversals== | ||
[[Image:cableReversal1.png|thumb]] | [[Image:cableReversal1.png|thumb]] | ||
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**reversal of leads aVR and aVF | **reversal of leads aVR and aVF | ||
It is possible to distinguish lead reversal and[[wikipedia:Dextrocardia|dextrocardia]] | It is possible to distinguish lead reversal and[[wikipedia:Dextrocardia|dextrocardia]] by watching the precordial leads. Dextrocardia will show an R wave inversion, wheras lead reversal will not. | ||
== | ==Artefacts== | ||
[[Image:Noise_move.png|thumb| | [[Image:Noise_move.png|thumb| Movement artefacts]] | ||
[[Image:ECG_Parkinson.png|thumb| | [[Image:ECG_Parkinson.png|thumb| Increasing movement artefacts in a Parkinson patient. The patient was in sinus rhythm! (which doesn't show on this short recording)]] | ||
[[Image:BaselineDrift.png|thumb| | [[Image:BaselineDrift.png|thumb| Baseline drift. The amplifier in the ECG machine has to re-find the 'mean'. This often occurs right after lead connection and after electric cardioversion.]] | ||
[[Image:electric_noise_ecg.png|thumb| | [[Image:electric_noise_ecg.png|thumb| Radiographic artefacts by a nearby electrical appliance. A typical example is a 100 Hz background distortion from fluorescent lights. Not to be confused with [[arrhythmias#atrial fibrillation|atrial fibrillation]].]] | ||
[[Image:electric_noise_ecg2.jpg|thumb| | [[Image:electric_noise_ecg2.jpg|thumb| Another example of an artefact caused by an electrical appliance. The patients rhythm is regular. This strip shows 10 QRS complexes.]] | ||
*Movement | Artefacts (disturbances) can have many causes. Common causes are: | ||
*Movement | |||
*Electrical interference | *Electrical interference | ||
{{clr}} | {{clr}} | ||