Clinical Outcomes of Persistent Atrial Fibrillation Ablation Using Ablation Index-guided Radiofrequency Catheter Ablation in Patients With Continuous Monitoring (AF-FAIR-MONTOR)

Atrial fibrillation (AF) is the commonest condition affecting the rhythm of the heart. Tablets to try to normalize the heart rhythm rarely work well. As a result, doctors have devised a treatment called catheter ablation in which special wires are used to deliver heat energy (called ablation lesions) on the inside surface of the heart. Unfortunately, in many patients (almost 1 in 2), some of these ablation lesions recover, and that leads to the recurrence of AF. Many of these patients then need a second procedure to deliver further ablation at these recovered areas.

Because of that problem, a software called Ablation Index has been developed to optimize the delivery of ablation lesions. The study aims to find out the effectiveness of the use of that Ablation Index in improving the ablation outcomes in patients with persistent AF. Also, the study will test the effectiveness of a new ablation approach using a catheter which is capable of delivering high-power during ablation and therefore requires shorter time for ablation. This will be achieved by following up patients who received ablation for 12 months to monitor their response to treatment in terms of freedom from AF.

This study will include patients with persistent AF which means AF episode(s) that last for longer than seven days. Patients participating in the study will undergo their ablation treatment either guided by ablation Index or delivered using high-power, short-duration (HPSD) ablation.

All participants will undergo implantation of a cardiac monitor, also knowns as loop recorder, to monitor for recurrence of atrial tachyarrhythmia following ablation. The monitor stores these ECG recordings which will be downloaded during review appointments that will be arranged 6 weeks, 3 months, 6 months and 12 months after the ablation procedure.

All participants will undergo implantation of a cardiac monitor, also knowns as a loop recorder, to monitor for recurrence of atrial tachyarrhythmia following ablation. The monitor stores these ECG recordings which will be downloaded during review appointments that will be arranged 6 weeks, 3 months, 6 months, and 12 months after the ablation procedure.

Study Overview

• Status: Withdrawn
• Conditions: Persistent Atrial Fibrillation
• Intervention / Treatment: Device: Ablation Index-guided ablation; Device: High-power, short-duration ablation using QDOT Micro catheter

Detailed Description

Single-center, prospective cohort study including patients with persistent AF (PeAF).

Primary Hypothesis:

Single AF ablation procedure that includes PVI achieved with point-by-point Wide Area Circumferential catheter ablation (WACA) either guided by Ablation Index (AI) targets or by HPSD ablation delivered using QDOT Micro catheter results in reduction in ATA as detected by insertable cardiac monitor (ICM).

Secondary hypotheses:

Single AF ablation procedure that includes PVI achieved with point-by-point WACA guided by Ablation Index targets has low incidence of adverse events and results in freedom from ATA, and improvement of AF symptoms and quality of life.

AF ablation procedures done by HPSD ablation delivered using QDOT Micro catheter will have shorter time and similar outcomes to procedures done using SmartTouch SF catheter guided by Ablation Index targets.

• Study Type: Observational

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Persistent atrial fibrillation patients who are 18 years or older and are indicated for atrial fibrillation ablation and have no exclusion criteria as listed above.

Description

Inclusion criteria:

• Aged over 18 years
• Persistent AF defined according to the 2017 HRS/EHRA/ECAS/APHRS/SOLAECE Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation, as AF episode that lasts longer than 7 days. (Calkins et al., 2017)
• Symptomatic despite drug treatment.
• Due to undergo AF ablation.

Exclusion criteria:

• Inability or unwillingness to receive oral anticoagulation with a Vitamin K antagonist (VKA) or non-VKA (NOAC) agent
• Previous catheter or surgical ablation procedure for AF
• Unwillingness or inability to complete the required follow-up arrangements
• Current pattern of paroxysmal AF
• Long standing persistent AF (continuous AF longer than 12 months before ablation)
• Prior prosthetic mitral valve replacement or severe structural cardiac abnormality
• Known infiltrative cardiomyopathy
• Known severe left ventricular systolic function (ejection fraction <35%)
• Pregnancy

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Ablation-Index guided ablation group; This is the prospective study group that will undergo persistent atrial fibrillation ablation guided by Ablation Index.	Device: Ablation Index-guided ablation; Radiofrequency catheter ablation guided by Ablation Index software.
High-power, short-duration ablation Group; This is another prospective group of patients who will undergo persistent atrial fibrillation ablation by high-power, short-duration using QDOT Micro catheter.	Device: High-power, short-duration ablation using QDOT Micro catheter; Radiofrequency catheter ablation guided by high-power, short-duration ablation using QDOT Micro catheter

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ICM-detected ATA burden	ICM-detected ATA burden measured as percentage of time spent in ATA (i.e., hours of ATA/hours of monitoring X 100)	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The occurrence of ATA recurrence of 2 minutes or more		12 month
QOL	QOL 6 and 12 months after initial ablation, as quantified by the validated AFEQT questionnaire.	6 and 12 months after initial ablation
Major complication rates	Major complications include cardiac tamponade, stroke/TIA, myocardial infarction, phrenic nerve paralysis, oesophageal perforation/atrio-oesophageal fistula, major vascular complications, and death.	Within 60 days after a PVI procedure

Collaborators and Investigators

• Sponsor: St. Louis University

Publications and helpful links

General Publications

• Hussein A, Das M, Riva S, Morgan M, Ronayne C, Sahni A, Shaw M, Todd D, Hall M, Modi S, Natale A, Dello Russo A, Snowdon R, Gupta D. Use of Ablation Index-Guided Ablation Results in High Rates of Durable Pulmonary Vein Isolation and Freedom From Arrhythmia in Persistent Atrial Fibrillation Patients: The PRAISE Study Results. Circ Arrhythm Electrophysiol. 2018 Sep;11(9):e006576. doi: 10.1161/CIRCEP.118.006576.
• Hussein A, Das M, Chaturvedi V, Asfour IK, Daryanani N, Morgan M, Ronayne C, Shaw M, Snowdon R, Gupta D. Prospective use of Ablation Index targets improves clinical outcomes following ablation for atrial fibrillation. J Cardiovasc Electrophysiol. 2017 Sep;28(9):1037-1047. doi: 10.1111/jce.13281. Epub 2017 Jul 26.

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2024
• Primary Completion (Estimated): June 30, 2024
• Study Completion (Estimated): June 30, 2025

Study Registration Dates

• First Submitted: June 1, 2022
• First Submitted That Met QC Criteria: June 1, 2022
• First Posted (Actual): June 6, 2022

Study Record Updates

• Last Update Posted (Actual): July 15, 2024
• Last Update Submitted That Met QC Criteria: July 11, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: Recurrence; Ablation; Ablation Index; Loop Recorder
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Arrhythmias, Cardiac; Atrial Fibrillation
• Other Study ID Numbers: 32462

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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