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Tachycardia: Difference between revisions
→Atrial Tachycardia
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===Atrial Tachycardia=== | ===Atrial Tachycardia=== | ||
====Pathophysiology:==== | ====Pathophysiology:==== | ||
Atrial tachycardia is a tachycardia resulting from fast firing in an ectopic focus or macro-reentry circuit in the atria. It has a frequency of above the 100bpm. In some patients the tachycardia has multiple foci. This results in different P-wave morphologies on the ECG. The result of firing can be due to all mechanisms of arrhythmias and is dependent on the causes of the | Atrial tachycardia (AT) is a tachycardia resulting from fast firing in an ectopic focus or macro-reentry circuit in the atria. It has a frequency of above the 100bpm. In some patients the tachycardia has multiple foci. This results in different P-wave morphologies on the ECG. The result of firing can be due to all mechanisms of arrhythmias and is dependent on the causes of the AT. Patient after earlier surgery or catheter ablation usually present with macro-reentry AT located around functional or anatomical sides of block. The atrial flutter is a type of AT, but due to its unique mechanism it is discussed separably. | ||
====Clinical diagnosis:==== | ====Clinical diagnosis:==== | ||
AT have a wide range clinical presentation. They can occur in paroxysms or can be the permanent underlying rhythm. Complaints of palpitation and a fast regular heart rate are common and as a result of the tachycardia complaints of dizziness, dyspnoea and syncope can be experienced. On the ECG an atrial tachycardia can be detected through the P-wave morphology. The P-wave has an other morpholgy depending on the foci of the atrial tachycardia. A ECG in resting condition can help distinguish different morphologies. Vagal manouvres or administration of adenosine can block the AV-conduction and reveal firing from the atrium, thereby clearly identifying the atrial source of the tachycardia. However sometimes only a electrophysiological study can differentiate between the different mechanisms of AT and localize the precise loacation or circuit of the AT. | |||
====Management:==== | ====Management:==== | ||
Atrial tachycardias can be treated with anti-arrhythmic medication, for instance with beta-blockers. If medication does not help, catheter ablation might locate the arrhythmia and ablate the source of repeated firing. | Atrial tachycardias can be treated with anti-arrhythmic medication, for instance with beta-blockers. If medication does not help, catheter ablation might locate the arrhythmia and ablate the source of repeated firing. | ||