Intra-atrial Reentrant Tachycardia (IART)
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Updated June 08, 2015.
Intra-atrial reentrant tachycardia (IART) is an uncommon type of supraventricular tachycardia (SVT).
As is the case with all types of reentrant tachycardias, patients with IART have an extra electrical connection in the heart. In this case, the extra connection is entirely located within one of the atria (the top chambers of the heart).
The symptoms include palpitations, lightheadedness and dizziness.
Episodes can last from several minutes to several hours.
In distinction to most other kinds of SVT, the circuit that causes this reentrant arrhythmia involves neither the sinus node nor the AV node, cardiac structures that are richly supplied by the vagus nerve. So with IART, treatments aimed at increasing the tone of the vagus nerve are usually not very effective at ending tachycardia. Instead, antiarrhythmic drugs are often given to stop episodes that do not go away in a reasonable period of time.
Long-term therapy with antiarrhythmic drugs to prevent IART is usually only somewhat effective, so ablation therapy is most often recommended to prevent repeated episodes of SVT in patients with IART.
Sources:
Saoudi N, Cosío F, Waldo A, et al. A classification of atrial flutter and regular atrial tachycardia according to electrophysiological mechanisms and anatomical bases; a Statement from a Joint Expert Group from The Working Group of Arrhythmias of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Eur Heart J 2001; 22:1162.
Updated June 08, 2015.
Intra-atrial reentrant tachycardia (IART) is an uncommon type of supraventricular tachycardia (SVT).
As is the case with all types of reentrant tachycardias, patients with IART have an extra electrical connection in the heart. In this case, the extra connection is entirely located within one of the atria (the top chambers of the heart).
The symptoms include palpitations, lightheadedness and dizziness.
Episodes can last from several minutes to several hours.
In distinction to most other kinds of SVT, the circuit that causes this reentrant arrhythmia involves neither the sinus node nor the AV node, cardiac structures that are richly supplied by the vagus nerve. So with IART, treatments aimed at increasing the tone of the vagus nerve are usually not very effective at ending tachycardia. Instead, antiarrhythmic drugs are often given to stop episodes that do not go away in a reasonable period of time.
Long-term therapy with antiarrhythmic drugs to prevent IART is usually only somewhat effective, so ablation therapy is most often recommended to prevent repeated episodes of SVT in patients with IART.
Sources:
Saoudi N, Cosío F, Waldo A, et al. A classification of atrial flutter and regular atrial tachycardia according to electrophysiological mechanisms and anatomical bases; a Statement from a Joint Expert Group from The Working Group of Arrhythmias of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Eur Heart J 2001; 22:1162.
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