Comparative Outcomes of Radiofrequency Ablation of Concealed and Manifest Accessory Pathways: a Single Center, Retrospective Observational Study

The aim of this observational, retrospective study is to evaluate, comparatively, procedural outcomes of APs (Accessory pathway) ablation according to the conduction properties (i.e., manifest vs. concealed) and to assess both short- and long-term outcomes of RFA (RF ablation).

Study Overview

• Status: Not yet recruiting
• Conditions: Atrioventricular Reentrant Tachycardias; Wolff-Parkinson-White (WPW) Syndrome

• Study Type: Observational
• Enrollment (Estimated): 220

Contacts and Locations

• Study Contact: Name: SImone Gulletta, MD; Phone Number: 02 2643 7484; Email: gulletta.simone@hsr.it
• Study Contact Backup: Name: Marcello Cosenza, MD; Phone Number: 02 2643 689; Email: cosenza.marcello@hsr.it

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Probability Sample

Study Population

Patients who consecutively underwent an electrophysiological (EP) study at San Raffaele Scientific Institute for EP study due to paroxysmal SVT with documented acessory pathway

Description

Inclusion Criteria:

1. Patients who consecutively underwent an electrophysiological (EP) study between 2005 and 2023 at San Raffaele Scientific Institute are included if they met one of the following criteria:

   Patients referred for EP study due to:

   • EITHER clinical suspicion of paroxysmal supraventricular tachycardia without prior documentation of ventricular pre-excitation and/or supraventricular arrhythmia (SVA) on 12-lead surface electrocardiogram, OR with electrocardiographic evidence of SVA, AND electrophysiological confirmation of atrioventricular re-entrant tachycardia (AVRT) as the arrhythmic mechanism.
   • Ventricular pre-excitation documented on serial 12-lead surface ECGs, with or without clinical episodes suggestive of AVRT, who underwent catheter ablation of the accessory pathway based on:

   The presence of high-risk electrophysiological features (e.g., short antegrade effective refractory period of the AP, rapid conduction during atrial fibrillation), or Induction of sustained AVRT during the EP study.

2. Aged between 5 to 60 years old

Exclusion Criteria:

1. Lack of pre-specified follow-up: only patients with at least 1 years follow-up ambulatory visit will be included in the study
2. REDO CA procedure

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Acute procedural success	At the end of the index procedure

Secondary Outcome Measures

Outcome Measure	Time Frame
Procedural complexity	From the end of the index procedure to discharge and at the ambulatory follow-up visits
Durability of successful radiofrequency ablation	From the end of the index procedure to discharge and at the ambulatory follow-up visits

Collaborators and Investigators

• Sponsor: IRCCS Ospedale San Raffaele

Publications and helpful links

General Publications

• Santinelli V, Radinovic A, Manguso F, et al. The natural history of asymptomatic ventricular pre-excitation a long-term prospective follow-up study of 184 asymptomatic children. J Am Coll Cardiol. 2009;53(3):275-280. doi:10.1016/j.jacc.2008.09.037
• Pappone C, Santinelli V, Rosanio S, et al. Usefulness of invasive electrophysiologic testing to stratify the risk of arrhythmic events in asymptomatic patients with Wolff-Parkinson-White pattern: results from a large prospective long-term follow-up study. J Am Coll Cardiol. 2003;41(2):239-244. doi:10.1016/s0735- 1097(02)02706-7
• Jackman WM, Wang XZ, Friday KJ, et al. Catheter ablation of accessory atrioventricular pathways (Wolff- Parkinson-White syndrome) by radiofrequency current. N Engl J Med. 1991;324(23):1605-1611. doi:10.1056/NEJM199106063242301

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: February 20, 2026
• First Submitted That Met QC Criteria: February 20, 2026
• First Posted (Actual): February 27, 2026

Study Record Updates

• Last Update Posted (Actual): February 27, 2026
• Last Update Submitted That Met QC Criteria: February 20, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Radiofrequency ablation; Accessory pathway; Wolff-Parkinson-White
• Additional Relevant MeSH Terms: Cardiac Conduction System Disease; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Disease; Arrhythmias, Cardiac; Congenital Abnormalities; Cardiovascular Abnormalities; Heart Defects, Congenital; Tachycardia, Reciprocating; Tachycardia; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Pathological Conditions, Signs and Symptoms; Syndrome; Tachycardia, Atrioventricular Nodal Reentry; Pre-Excitation Syndromes; Wolff-Parkinson-White Syndrome
• Other Study ID Numbers: AP-STUDY

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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