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Atrial Flutter: Difference between revisions
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| p_wave = negative sawtooth in lead II | | p_wave = negative sawtooth in lead II | ||
| adenosine = temporary reduced AV conduction (eg 4:1) | | adenosine = temporary reduced AV conduction (eg 4:1) | ||
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During atrial flutter the atria depolarize in an organized circular movement. This is caused by [[Arrhythmias#Re-entry|re-entry]]. The atria contract typically at around 300 bpm, which results in a fast sequence of p-waves in a sawtooth pattern on the ECG. For most AV-nodes this is way to fast to be able to conduct the signal to the ventricles, so typically there is a 2:1, 3:1 or 4:1 block, resulting in a ventricular frequency of 150, 100 or 75 bpm respectively. Often the grade of block changes every couple of beats, resulting in e.g. 2:1, or 3:1 blocks and a somewhat irregular ventricular heart rate. The saw-tooth is especially prominent in lead II, this lead normally shows constant electrical activity: it is never horizontal. Causes and risk of atrial flutter are comparable to atrial fibrillation. | During atrial flutter the atria depolarize in an organized circular movement. This is caused by [[Arrhythmias#Re-entry|re-entry]]. The atria contract typically at around 300 bpm, which results in a fast sequence of p-waves in a sawtooth pattern on the ECG. For most AV-nodes this is way to fast to be able to conduct the signal to the ventricles, so typically there is a 2:1, 3:1 or 4:1 block, resulting in a ventricular frequency of 150, 100 or 75 bpm respectively. Often the grade of block changes every couple of beats, resulting in e.g. 2:1, or 3:1 blocks and a somewhat irregular ventricular heart rate. The saw-tooth is especially prominent in lead II, this lead normally shows constant electrical activity: it is never horizontal. Causes and risk of atrial flutter are comparable to atrial fibrillation. | ||
{{clr}} | {{clr}} | ||
==Examples= | |||
<gallery> | |||
Image:aflutr_ecg.jpg|The arrows mark the flutter waves. This is an example of an alternating 2:1 and 3:1 block. | |||
Image:ECG_Aflutt.jpg|Atrial flutter with 2:1 conduction. | |||
</gallery> | |||