Preclinical Procedure
The study protocol was approved by the Institutional Animal Care and Use
Committee of GMD Laboratories (Pomona, CA). Discrete ventricular lesions
and atrial lesion sets were studied using a Yorkshire hybrid swine model
(N=10, 50-70 kg, male and female) in acute (N=8) and chronic procedures
(N=2). Chronic procedures included recovery post-index procedure and
invasive remapping at 30 days to analyze lesion durability and
pathology. All catheters were introduced via femoral access under
inhaled anesthesia (isoflurane, 1-5%) and without paralytics.
Intravenous heparin was administered to maintain an activated clotting
time ≥350 seconds prior to catheter introduction.
Operators guided the LAF catheter into bloodpool to determine a
no-contact location and establish a LI baseline. After navigating the
catheter to the myocardium, electrograms and ICE were used to determine
CTC. No catheter-tissue contact (NTC) with close proximity to tissue
(approximately <2mm) induced ≤∆10Ω from baseline, Low
catheter-tissue contact (LTC) induced ∆11-29Ω, and High catheter-tissue
contact (HTC) induced ≥∆30Ω (Figure 2 ).