Lattice-Tip Focal Ablation Catheter That Toggles Between Radiofrequency and Pulsed Field Energy to Treat Atrial Fibrillation: A First-in-Human Trial

- The tissue selectivity of pulsed field ablation (PFA) provides safety advantages over radiofrequency ablation (RFA) in treating atrial fibrillation (AF). "One-shot" PFA catheters have been shown capable of performing pulmonary vein isolation (PVI), but not flexible lesion sets such as linear lesions. A novel lattice-tip ablation catheter with a compressible 9-mm nitinol tip is able to deliver either focal RFA or PFA lesions, each in 2-5 seconds. - In a 3-center, single-arm, first-in-human trial, the 7.5-French lattice catheter was used with a custom mapping system to treat paroxysmal or persistent AF. Toggling between energy sources, point-by-point PV encirclement was performed using biphasic PFA posteriorly, and either temperature-controlled irrigated RFA or PFA anteriorly (RF/PF or PF/PF, respectively). Linear lesions were created using either PFA or RFA. - The 76-patient cohort included 55 paroxysmal and 21 persistent AF patients undergoing either RF/PF (40 patients) or PF/PF (36 patients) ablation. The PVI therapy duration time (transpiring from first to last lesion) was 22.6±8.3 min/patient, with a mean of 50.1 RF/PF lesions/patient. Linear lesions included 14 mitral (4 RF / 2 RF+PF / 8 PF), 34 LA roof (12 RF / 22 PF) and 44 CTI (36 RF / 8 PF) lines, with therapy duration times of 5.1±3.5, 1.8±2.3 and 2.4±2.1 min/patient, respectively. All lesion sets were acutely successful, using 4.7±3.5 min of fluoroscopy. There were no device-related complications, including no strokes. Post-procedure esophagogastroduodenoscopy revealed minor mucosal thermal injury in 2 of 36 RF/PF and 0 of 24 PF/PF patients. Post-procedure brain MRI revealed DWI+/FLAIR- and DWI+/FLAIR+ asymptomatic lesions in 5 and 3 of 51 patients, respectively. - A novel lattice-tip catheter could safely and rapidly ablate AF using either a combined RF/PF approach (capitalizing on the safety of PFA and the years of experience with radiofrequency energy) or an entirely PF approach.