RADAR Clinical Trial

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).

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.