Background: A novel expandable lattice-tip catheter delivers irrigated RF energy to create a large “thermal footprint”- which in preclinical studies can project lesion depth. This catheter is being studied to treat AF, but in theory, it may also be ideally suited for ablation of the thick myocardial substrate of scar VT.
Objective: To assess the safety and efficacy of the lattice catheter to eliminate scar-related VT.
Methods: In a pilot 3-center study, scar VT patients underwent catheter ablation with the latticecatheter with its compatible mapping system (Sphere-9 & Prism-1; Affera Inc). The catheter has 9 minielectrodes with thermocouples to allows substrate mapping, and temp-guided saline irrigated RF ablation (Tmax60°C; 30-60 sec). After anatomy creation, standard ablation strategies included substrate and entrainment mapping.
Results: A total of 12 pts underwent VT ablation: age 62±10.2, 11 male, LVEF 36.3±14.2%, BMI 30.5, ICD in 91.7%, AAD use 91.7%. The VT substrate was: ischemic (n=9), non-ischemic (n=1) or ARVC (n=3). The procedures were with either general anesthesia (n=3) or conscious sedation (n=9). At start, VT was inducible in 10 of 12 (83%) pts. A total of 20.8±10.8 RF applications were placed, for total RF duration of 11.0±5.4 min. The total ablation time (from first to last lesion) was 46.1±22.6 min, procedure time was 127.6±33.5 min, fluoroscopy for 5.2±5.6 min, and 713±326 ml saline infused. After ablation, VT was non-inducible in all pts. There were no complications. Over 89±75 days follow up of, VT recurred in 2 of 12 (17%) pts.
Conclusion: In this first in human early experience with scar VT ablation, large thermal footprint ablation demonstrated promising results.