Right Phrenic Nerve Localization on CT for Ablation

NCT ID: NCT07330791

Last Updated: 2026-01-09

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 80 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-04-01
• Study Completion Date: 2025-09-29

Brief Summary

The anatomical location of the right phrenic nerve (RPN) in close proximity to the right pulmonary veins has become a critical consideration for electrophysiologists performing pulmonary vein isolation, the cornerstone treatment for atrial fibrillation. Although radiofrequency ablation in this region is rarely associated with complications-unlike cryoballoon ablation-the proximity of the RPN to the ablation site is considered the most widely accepted mechanism of nerve injury. Therefore, accurately defining its anatomical course is essential to prevent complications.

This concern extends to any ablation procedure performed near the RPN, including those targeting the lateral-posterior region of the right atrium, particularly during atrial tachycardia ablation or cardioneuroablation. Several methods have been used to precisely localize the RPN. The most commonly employed technique is phrenic nerve stimulation; however, there is growing interest in the use of computed tomography (CT) to identify structures running parallel to the nerve-such as the pericardiophrenic artery and vein-enhanced with contrast. Three-dimensional reconstruction through image segmentation has proven useful in defining the anatomy of cardiac chambers and adjacent extracardiac structures.

This study aims to compare two approaches for visualizing the course of the right phrenic nerve: one based on computed tomography imaging and the other on the nerve's response to stimulation during the procedure. This comparison will allow us to assess the concordance between imaging findings and intra-procedural observations, ultimately contributing to improved procedural safety.

Conditions

We Evaluated CT-guided Localization of the Right Phrenic Nerve to Enhance Safety in Transcatheter Ablation

Study Design

• Observational Model Type: OTHER
• Study Time Perspective: PROSPECTIVE

Study Groups

This study will enroll patients undergoing two distinct types of ablative procedures g

A total of 80 consecutive patients will be included:

• 60 patients will be enrolled using a single electric stimulation output set at 20 mA, 2 ms amplitude width and 1000 ms cycle length
• 20 patients will be enrolled using a double electric stimulation output set respectively at 10 mA and 20 mA (2 ms amplitude width and 1000 ms cycle length)

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• Ability to provide informed consent
• Patients who have undergone or will undergo transcatheter AF ablation or CNA
• Availability of 64-slice contrast-enhanced MDCT with RPN segmentation using ADAS® software prior to ablation
• Age ≥ 18 years

Exclusion Criteria

• Inability to provide informed consent
• Inability to perform contrast-enhanced CT before transcatheter AF ablation or CNA
• Age < 18 years

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Centro Medico Teknon

OTHER

Sponsor Role: lead

Responsible Party

Antonio Berruezo, MD, PhD

Chief of Electrophysiology Unit

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Antonio Berruezo

Barcelona, Barcelona, Spain

Countries

Spain

Other Identifiers

Phrenic nerve CT-Localization

Identifier Type: -

Identifier Source: org_study_id