BackgroundVentricular arrhythmias commonly originate from the ventricular outflow tract (VOT). It remains unexplored whether pulsed-field ablation (PFA) can create durable lesions safely at the VOT. ObjectiveThis study aimed at evaluating the feasibility and safety of a novel PFA catheter to deliver focal ablation to the VOT, especially pulmonary and aortic sinus cusps (PSCs and ASCs). MethodsTwelve swine were divided into three groups: 24-hour, 2-week, and 4-week post-ablation. PFA was delivered to pre-defined sites of PSCs and ASCs with a focal point catheter, positioned via mapping system, fluoroscopy, and intracardiac echocardiography (ICE). Electrophysiologic assessment, coronary angiography, transesophageal echocardiogram (TEE), gross and histologic examination were performed to evaluate the impact of PFA delivery on cardiac structure and function. ResultsAll subjects survived, and no adverse events were observed. There was a significant decrease in voltage amplitude and increase in pacing thresholds at PSCs and ASCs. There were no significant differences in A-H or H-V intervals between pre- and post-ablation (A-H, P = .70; H-V, P = .90). After PFA delivery to ASCs, coronary arteries were fully perfused in each heart, without ST-segment elevation observed. No severe valvular dysfunction was observed based on ICE and TEE. Gross and histologic examination confirmed the creation of well-demarcated lesions at the targeted sites without damage to adjacent structures. ConclusionPFA delivered via the focal point catheter could create durable lesions at PSCs and ASCs without damage to coronary arteries, atrioventricular block, or valvular dysfunction, indicative of the feasibility and safety of this novel PFA catheter at the VOT.
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