Initial Clinical Experience with Percutaneous Endocardial Septal Pulsed Field Ablation in Hypertrophic Obstructive Cardiomyopathy: A First-in-Human Case Series

Figures

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  Figure 1. Procedural illustration of pulsed field ablation (PFA) for hypertrophic obstructive cardiomyopathy guided by fluoroscopy, 3-dimensional electroanatomic mapping, and intracardiac echocardiography (ICE). (A) Anteroposterior fluoroscopic view during pressure measurement, showing the pressure measurement catheter (red arrow), ventricular pacing lead, and coronary sinus electrode catheter (white arrow). (B) Fluoroscopic image obtained immediately before ablation, showing the PFA catheter (red arrow) and ICE catheter (white arrow). (C) ICE image obtained before ablation, showing the obstructive region (red arrow), mitral valve leaflet (white arrow), and systolic anterior motion. (D,E) Three-dimensional electroanatomic maps obtained during ablation. White points indicate the mitral annulus, yellow points indicate the His bundle or bundle branch region, and red points indicate the ablation sites. (F) ICE image obtained during ablation, showing good apposition of the PFA catheter to the interventricular septum.

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  Figure 2. Cardiac magnetic resonance late gadolinium enhancement images before pulsed field ablation and at 2-month follow-up. Preprocedural 4-chamber and short-axis images are shown in (A) and (C), respectively. At 2 months, the corresponding 4-chamber (B) and short-axis (D) images show a new focal area of late gadolinium enhancement on the left ventricular aspect of the basal-to-mid interventricular septum near the left ventricular outflow tract (red arrows). This lesion was not present before ablation and was spatially concordant with the ablation target region, consistent with localized postprocedural myocardial injury within the targeted septum.

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  Figure 3. Periprocedural and 2-month changes in echocardiographic parameters in patients with hypertrophic obstructive cardiomyopathy. (A) Resting left ventricular outflow tract (LVOT) gradient. (B) Provoked LVOT gradient. (C) Maximum septal thickness. (D) Left ventricular ejection fraction (LVEF). (E) Left ventricular end-diastolic diameter (LVEDD). (F) Left ventricular posterior wall thickness at end-diastole (LVPWd). Each line represents an individual patient. Measurements were obtained at baseline, immediately after completion of the entire index procedure, including pulmonary vein isolation when performed, and at 2-month follow-up.

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  Figure 4. Changes in 6 min walk distance and Kansas City Cardiomyopathy Questionnaire score from baseline to 2-month follow-up. (A) Six-minute walk distance (6MWD). (B) Kansas City Cardiomyopathy Questionnaire (KCCQ) overall score. Each line represents an individual patient. Assessments were performed at baseline and at 2-month follow-up after the index procedure.

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  Figure 5. Periprocedural and 2-month changes in electrocardiographic parameters in patients with hypertrophic obstructive cardiomyopathy. (A) Heart rate (HR). (B) PR interval. (C) QRS duration. (D) Corrected QT interval (QTc). Each line represents an individual patient. Standard 12-lead electrocardiographic measurements were obtained at baseline, immediately after completion of the index procedure, on postprocedural day 1, and at 2-month follow-up.