Treatment of Re-entry Tachycardias

Measures to increase AV block may terminate the arrhythmia by blocking the re-entry circuit:

• Synchronised DC cardioversion if haemodynamically unstable, or if failed vagal & drug therapy
• Vagal manoeuvres, e.g. Modified Valsalva Manoeuvre- asking patient to blow into 20ml syringe, followed by repositioning them supine with passive leg raise
• Adenosine potent if vagal manoeuvres fail, in orthodromic
• Diltiazem, Verapamil & Beta-Blockers may be appropriate if failure to respond to vagal manoeuvres & adenosine in orthodromic AVRT
• If distinguished from VT, treatment of antidromic AVRT may involve Class I antiarrhythmics
• Outside of the acute episode, catheter ablation is recommended for symptomatic recurrent AVRT.