3D Mapping Versus Conventional Ablation in AVNRT (MAP-AVNRT)

Three-Dimensional Electroanatomical Mapping Versus Conventional Fluoroscopy-Guided Slow Pathway Ablation for Typical Atrioventricular Nodal Re-Entrant Tachycardia: A Prospective Randomized Study

This prospective randomized interventional study compared conventional fluoroscopy-guided slow pathway ablation versus three-dimensional electroanatomical mapping-guided ablation in patients with electrophysiologically confirmed typical atrioventricular nodal re-entrant tachycardia (AVNRT). A total of 108 patients were screened for eligibility, of whom 80 eligible patients were randomized in a 1:1 ratio to either conventional fluoroscopic ablation or 3D mapping-guided ablation. Following post-randomization dropouts, the final analysis included 38 patients in the conventional group and 36 patients in the 3D mapping group. The study evaluated fluoroscopy exposure, procedural efficacy, complete slow pathway elimination, procedural success, complications, and arrhythmia recurrence during follow-up.

Study Overview

• Status: Completed
• Conditions: Supraventricular Tachycardia (SVT); Atrioventricular Nodal Reentry Tachycardia
• Intervention / Treatment: Procedure: Conventional Slow Pathway Ablation; Procedure: 3D Electroanatomical Mapping-Guided Ablation

Detailed Description

Atrioventricular nodal re-entrant tachycardia (AVNRT) is one of the most common forms of paroxysmal supraventricular tachycardia. Catheter ablation targeting the slow AV nodal pathway is considered definitive therapy with high procedural success rates.

Conventional fluoroscopy-guided ablation mainly relies on anatomical landmarks and intracardiac electrogram interpretation. However, fluoroscopy exposure remains an important concern for both patients and operators. Three-dimensional electroanatomical mapping systems allow detailed reconstruction of the triangle of Koch and facilitate substrate-guided ablation using voltage, activation, and fractionated electrogram mapping techniques. These systems may reduce fluoroscopy exposure and improve procedural precision and efficacy.

This prospective randomized two-arm interventional study was conducted at the Cardiology Department, Kafr El-Sheikh University Hospital, between December 2023 and November 2025. A total of 108 consecutive patients with symptomatic supraventricular tachycardia suggestive of AVNRT were screened for eligibility. Following assessment according to predefined inclusion and exclusion criteria, 80 eligible patients with electrophysiologically confirmed typical AVNRT were enrolled and randomized in a 1:1 ratio to either conventional fluoroscopy-guided slow pathway ablation (Conventional group, n = 40) or three-dimensional electroanatomical mapping-guided slow pathway ablation (3D group, n = 40).

During the study period, post-randomization dropouts and exclusions occurred in both groups. Consequently, the final analysis included 38 patients in the conventional ablation group and 36 patients in the 3D mapping-guided ablation group.

In the conventional arm, ablation was performed using standard fluoroscopic anatomical landmarks and intracardiac electrogram criteria within the triangle of Koch. In the 3D mapping arm, high-density electroanatomical mapping using CARTO or EnSite X systems was performed with integrated voltage, activation, and fractionated electrogram mapping to identify optimal ablation targets.

Primary outcomes included fluoroscopy time, fluoroscopy dose, complete slow pathway elimination, and procedural success defined as non-inducibility of sustained AVNRT after ablation. Secondary outcomes included total procedure duration, number and duration of radiofrequency applications, complications, recurrence during follow-up, hospital stay duration, need for redo ablation, and predictors of complete slow pathway elimination.

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Kafr el-Sheikh Governorate
    • Kafr ash Shaykh, Kafr el-Sheikh Governorate, Egypt, 11355
      • Kafr Elsheikh Univfersity Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Sustained symptomatic supraventricular tachycardia with surface ECG features highly suggestive of atrioventricular nodal re-entrant tachycardia (AVNRT).
• Electrophysiologically confirmed typical (slow-fast) AVNRT during the index electrophysiology study.
• Ability to provide written informed consent.

Exclusion Criteria:

• Coexisting arrhythmia requiring concurrent catheter ablation during the same procedure.
• Non-inducible AVNRT at the time of electrophysiological study.
• Antiarrhythmic drug use within 48 hours before the procedure or ongoing amiodarone therapy.
• Hemodynamic instability precluding safe catheter manipulation.
• Pregnancy.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Conventional Fluoroscopy-Guided Ablation; Patients underwent conventional fluoroscopy-guided slow pathway ablation using standard anatomical landmarks and intracardiac electrogram criteria within the triangle of Koch.	Procedure: Conventional Slow Pathway Ablation; Conventional fluoroscopy-guided catheter ablation of the slow AV nodal pathway using anatomical landmarks and intracardiac electrogram criteria within the triangle of Koch.; Other Names: Conventional Fluoroscopy-Guided Ablation
Experimental: 3D Electroanatomical Mapping-Guided Ablation; Patients underwent three-dimensional electroanatomical mapping-guided slow pathway ablation using CARTO or EnSite X systems with integrated voltage, activation, and fractionated electrogram mapping.	Procedure: 3D Electroanatomical Mapping-Guided Ablation; Three-dimensional electroanatomical mapping-guided catheter ablation of the slow AV nodal pathway using CARTO or EnSite X systems with voltage and activation mapping guidance.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Fluoroscopy Radiation Dose During Catheter Ablation	Total fluoroscopy radiation dose measured during the catheter ablation procedure, reported in mGy.	At completion of the index ablation procedure
Total Fluoroscopy Exposure Time During Catheter Ablation	Total duration of fluoroscopy exposure during the catheter ablation procedure, reported in minutes.	At completion of the index ablation procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Complete Slow Pathway Elimination	Complete abolition of slow pathway conduction and disappearance of the anterograde AH jump following catheter ablation.	At completion of the index ablation procedure
Number of Participants with Acute Procedural Success	Acute procedural success defined as non-inducibility of sustained AVNRT after catheter ablation under baseline conditions and following isoproterenol infusion.	At completion of the index ablation procedure

Collaborators and Investigators

• Sponsor: Kafrelsheikh University

Study record dates

Study Major Dates

• Study Start (Actual): December 30, 2023
• Primary Completion (Actual): November 23, 2025
• Study Completion (Actual): November 23, 2025

Study Registration Dates

• First Submitted: May 23, 2026
• First Submitted That Met QC Criteria: June 1, 2026
• First Posted (Actual): June 5, 2026

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 1, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Catheter Ablation; Electrophysiology; Fluoroscopy; AVNRT; Electroanatomical Mapping; Three-Dimensional Mapping; Slow Pathway Ablation
• Additional Relevant MeSH Terms: Cardiac Conduction System Disease; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Tachycardia, Reciprocating; Tachycardia; Pathological Conditions, Signs and Symptoms; Tachycardia, Supraventricular; Tachycardia, Atrioventricular Nodal Reentry
• Other Study ID Numbers: AVNRT-3D-2025

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Individual participant data (IPD) sharing plans have not yet been finalized at the time of study registration.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No