RADAR Clinical Trial

This prospective, multicenter, observational study will examine the ability of real time electrogram processing mapping to identify driver domains to target for ablation in persistent AF patients.

ABSTRACT: Recent clinical trials have shown that targeting rotors and focal impulses (FIs) during atrial fibrillation (AF) ablation improves outcomes. This study evaluated whether a novel computational mapping algorithm (CMA) could identify FIs and rotors, and characterize rotors when incidental ablation resulted in rhythm changes. Three-dimensional (3D) left atrial electroanatomic maps were created from signals recorded from multipolar circular mapping catheters in 61 patients undergoing persistent AF ablation. Forty of 61acquired patient datasets were of adequate quality for analysis CMA, employing an AF pattern recognition algorithm, creating 3D panoramic AF maps identifying drivers of AF (FI and rotors) post procedure. Rotors were further classified as substrate (SBR) or non-substrate based (NSBR) on the basis of rotor stability, proximity to voltage transition zones and complex fractionated atrial electrograms (CFAEs). Incidentally ablated identified AF drivers, including SBRs and NSBRs, were evaluated for rhythm changes. A total of 172 drivers were identified in 40 patients (2.2 drivers/patient). Seventy percent were rotors (120/172) and 30% were FIs (52/172). Sixty-seven percent of rotors were classified as SBR vs 33% as NSBR. Incidental ablation of SBRs resulted in rhythm change 91% of the time versus only 24% of the time for NSBR (p<0.0001).

AF mapping (utilizing CMA) will be performed and used to point the operator to regions within a heart chamber that should be interrogated further for suspicious electrogram activity, as measured by the St. Jude Ensite System, and ablated if the suspicious electrogram activity persists.

This software enables high resolution temporospatial mapping of atria for the identification of drivers of AF. CMA receives data from standard of care, commercially available 3D Mapping Systems (St. Jude Ensite System) and catheters and processes the data in a unique way. Electrogram and anatomy data are fed from the commercially available 3D Mapping System to an adjacent laptop computer, via an Ethernet connection, that is running CMA. CMA then processes the electrogram data and generates a map of where the potential AF driver domains are located and superimposes those potential AF driver domain targets onto the 3D geometry of the anatomy (provided by the 3D mapping system).

Acute Procedural Outcomes as defined by termination of Atrial Fibrillation into normal sinus rhythm (NSR) or atrial tachycardia (AT)

Number of Participants freedom from recurrent Atrial Tachycardia/Atrial Fibrillation with no use of Anti-Arrhythmic Drugs (AAD)

Number of Participants Free recurrent Atrial Tachycardia/Atrial Fibrillation with either some or no use of Anti-Arrhythmic Drugs

Inclusion Criteria: ≥ 18 years of age. Patients are considered eligible if they have symptomatic or drug-refractory AF and are planned to undergo a catheter ablation procedure for persistent AF (ether a first procedure or a redo procedure) Ability to understand the requirements of the study and sign the informed consent form. Willingness to adhere to study restrictions and comply with all post-procedural follow-up requirements Projected lifespan greater than 1 year. Exclusion Criteria: They have long-standing persistent AF prior to the first procedure (defined as AF greater than one year's duration). Rheumatic heart disease Current intra-cardiac thrombus History of MI or Coronary Artery Bypass Grafting (CABG) within 6 weeks Unstable angina CVA or TIA within 3 months Contraindication to anticoagulation Class IV HF Unable to sign consent Projected lifespan of < 1 year Women known to be pregnant or to have positive beta-HCG (Human Chorionic Gonadotropin). Participation in another study that would interfere with this study.

Choudry S, Mansour M, Sundaram S, Nguyen DT, Dukkipati SR, Whang W, Kessman P, Reddy VY. RADAR: A Multicenter Food and Drug Administration Investigational Device Exemption Clinical Trial of Persistent Atrial Fibrillation. Circ Arrhythm Electrophysiol. 2020 Jan;13(1):e007825. doi: 10.1161/CIRCEP.119.007825. Epub 2020 Jan 16.