Cardiology Made Clearwith Dr. Freeman
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CLINICIAN SVT GUIDE · SECTION 3 OF 3

Treatment & ablation.

Connect each SVT mechanism to its treatment target and discuss options with the patient.

An EP study identifies the mechanism and guides ablation. Treatment targets differ for each rhythm.

AVNRT · Modify the slow pathway

Ablation interrupts the loop while preserving normal AV conduction. It is highly effective; AV block requiring a pacemaker is an uncommon but important risk to discuss.[6]

Magnified AV nodal region showing a blue catheter tip treating the orange slow pathway, separate from the labeled AV node and blue fast pathway. The blue catheter shaft is labeled Ablation catheter.
The catheter tip treats the slow-pathway region to interrupt the AVNRT circuit while aiming to preserve normal AV node conduction. The pathway overlay and catheter position are simplified for teaching.
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AVRT · Eliminate the accessory pathway

Ablation treats the extra connection. Pathway location determines access and risk; pathways near the normal conduction system require particular care.[2]

Labeled AVRT ablation illustration showing one blue catheter passing smoothly from the right atrium through the atrial septum into the left atrium, with its electrode tip treating a left lateral accessory pathway. The blue catheter shaft is labeled Ablation catheter.
Example of a left-sided pathway treated through transseptal access. Other pathway locations and approaches differ.
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Focal atrial tachycardia · Map and treat the focus

Ablation targets the source. It is an important option for recurrent symptomatic or incessant tachycardia, especially with suspected tachycardia-induced cardiomyopathy.[3]

Labeled heart showing a blue ablation catheter curving through the right atrium to treat the extra electrical focus, separate from the SA node and AV node.
Example of focal right atrial tachycardia ablation; the actual target depends on EP mapping.
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When medication or observation is appropriate

Observation may suit infrequent, well-tolerated episodes. Beta blockers or diltiazem/verapamil may be options for selected patients without pre-excitation; consider blood pressure, ventricular function, and contraindications. Specialist antiarrhythmic choices depend on the rhythm and underlying heart disease.[1]

Ablation discussions should include vascular injury, bleeding, rare serious complications, and recurrence. Anticoagulation is not routinely indicated solely for AVNRT, AVRT, or focal atrial tachycardia; assess any separate indication, including coexisting AF/flutter.[3]

Referral message: “You have a fast rhythm that may come from an electrical loop or an extra atrial source. An electrophysiologist can identify the mechanism and discuss whether ablation or medication best fits your symptoms and preferences.”
Clinical references
  1. 2015 ACC/AHA/HRS SVT guideline executive summary.
  2. ESC: accessory pathway mechanisms and ablation (2021).
  3. 2019 ESC SVT guideline.
  4. 2025 AHA adult tachyarrhythmia with a pulse algorithm.
  5. REVERT randomized trial (Lancet, 2015).
  6. Multicenter AVNRT ablation outcomes study (JACC: Clinical Electrophysiology).
  7. AHA: tachycardia and supraventricular rhythms.
  8. NHS: SVT and potentially curative catheter ablation.

Reviewed October 11, 2026. Illustrations are simplified teaching diagrams.