Outcomes of High Power Application in Catheter Ablation of Paroxysmal Atrial Fibrillation Guided by Unipolar Signal Modification.

Not Applicable

• Conditions: Atrial Fibrillation Paroxysmal

• Registration Number: NCT04447300
• Lead Sponsor: Assiut University

Brief Summary

Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation procedures in patients with paroxysmal atrial fibrillation (PAF) \[1\]. However, the incidence of atrial fibrillation (AF) recurrence remains high \[2\], mostly due to pulmonary vein (PV) reconnection \[1\], emphasizing the formation of transmural lesions to achieve complete conduction block along the ablation lines \[3\].

Previous studies have shown that elimination of the negative component of the unipolar electrogram (UP-EGM) during radiofrequency applications reflects transmural lesions. The persistence of such a negative component consistently corresponds to non-trans mural lesions \[4\].

Detailed Description

Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation procedures in patients with paroxysmal atrial fibrillation (PAF) \[1\]. However, the incidence of atrial fibrillation (AF) recurrence remains high \[2\], mostly due to pulmonary vein (PV) reconnection \[1\], emphasizing the formation of transmural lesions to achieve complete conduction block along the ablation lines \[3\].

Previous studies have shown that elimination of the negative component of the unipolar electrogram (UP-EGM) during radiofrequency applications reflects transmural lesions. The persistence of such a negative component consistently corresponds to non-trans mural lesions \[4\].

The high-power short duration (HPSD) RF application applies to all RF energies delivered at more than 40 W \[5\]. Higher the power more is the resistive heating causing wider tissue injury \[5\]. The lesion size with HPSD is larger in width but lesser in depth compared to lower powers with longer duration \[5\]. In contrast, RF applications of lower power and longer duration result in larger dissipation of RF energies deep into the tissues due to conductive heating causing tissue destruction at greater depths \[6\]. Hence, there is a risk of collateral tissue damage \[5\].

HPSD ablation has been advocated as a means to minimize the risk of collateral organ damage as the lesions are smaller in depth. However, Maintaining a high power for a constant duration in the absence of a guide may not be the right strategy \[5\].

Unipolar waveform modification by complete elimination of the negative component may serve as a guide for HPSD ablation \[5\].

Study Timeline

• Study First Submitted: 2020-06-23
• Study First Submitted QC: 2020-06-24
• Study First Posted: 2020-06-25
• Status Verified: 2021-01
• Last Update Submitted: 2021-01-12
• Last Update Posted: 2021-01-13
• Study Start: 2021-09-20
• Primary Completion: 2022-10-01
• Study Completion: 2023-03-20

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

• Paroxysmal atrial fibrillation

Exclusion Criteria

• Age< 18 or > 80 years old,
• Atrium (LA) diameter > 50 mm,
• The presence of a mechanical mitral valve prosthesis,
• Left ventricular ejection fraction < 40%,
• Abnormal thyroid function,
• Contraindication to anticoagulant therapy,
• Current malignancy,
• Prior catheter or surgical AF ablation.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Ablation success at 6-month after the index procedure	6 months	Ablation success is defined as no recurrence with no anti-arrhythmic drugs by taking history of symptoms from the patient and by Holter 48 Hours.