[Efficacy and safety of transthoracic echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation for the treatment of patients with obstructive hypertrophic cardiomyopathy].

FIGURE 1. Description of Liwen RF™ ablation system and main findings. Liwen RF™ (Hangzhou Nuo Cheng Medical Instrument Co., Ltd., Hangzhou, Zhejiang, China) is a novel radiofrequency ablation system with a stepless adjustable length needle electrodes for percutaneous intramyocardial septal radiofrequency ablation (PIMSRA). The device is an integrated system, comprising ablation electrode kit, ablation generator, cooling system, and patient circuit.

FIGURE 2. Post-procedure characteristics of patients. A systematic evaluation at 12 months after procedure showed that Liwen RF™ was effective in relieving outflow tract obstruction and symptoms compared to baseline. (A) Left ventricular outflow tract gradient under calm state. (B) Left ventricular outflow tract gradient under provocation of treadmill motion. (C–E) Measured in calm state. (C) Maximum thickness of interventricular septum. (D) Change in left ventricular ejection fractions. (E) Grades of mitral valve systolic anterior motion. (F) Results of the 6-min walk test. (G) The distribution of NYHA function class among patients. (H) Incidence of the three main symptoms of chest pain, shortness of breath, and syncope/pre-syncope. IVS, Interventricular septum; LVEF, Left ventricular outflow tract; LVOTG, Left ventricular outflow tract gradient; NYHA, New York heart association; SAM, systolic anterior motion; 6MWT, 6-min walk test.