Efficacy Analysis of Percutaneous Endocardial Septal Radiofrequency Ablation Guided by Ablation Index in the Treatment of Drug‐Resistant Hypertrophic Obstructive Cardiomyopathy

Background Percutaneous endocardial septal radiofrequency ablation (PESA) is a novel interventional treatment for hypertrophic obstructive cardiomyopathy (HOCM). However, further research is required to confirm its safety and efficacy. Currently, there are no studies reporting the use of Ablation Index (AI) for energy guidance during PESA. Methods A total of 20 patients with drug‐resistant HOCM were enrolled. All patients had previously received the maximum tolerated doses of beta‐blockers and/or calcium channel blockers. All patients underwent PESA guided by AI with the assistance of intracardiac echocardiography. The primary efficacy endpoint was the change in left ventricular outflow tract gradient (LVOTG) from baseline to 1 month postoperation. Results The mean age of the patients was 55.75 ± 14.28 years, with an equal distribution of females and males. All patients completed a 1‐month postoperative follow‐up evaluation. Additionally, some patients underwent longer‐term follow‐up. The overall median follow‐up duration was 94 days (IQR: 361.3 days). Regarding the primary efficacy endpoint, LVOTG significantly decreased to 44.15 ± 25.80 mmHg at 1 month postoperation ( p < 0.0001). As for secondary endpoints, LVOTG decreased from 68.75 ± 24.92 mmHg to 45.70 ± 26.55 mmHg ( p = 0.0003), and the maximum interventricular septum thickness at end‐diastole decreased from 19.77 ± 5.38 mm to 18.25 ± 5.41 mm ( p = 0.0104). The average distance covered in the six‐minute walk test increased from 180.00 ± 76.44 m to 317.50 ± 98.38 m ( p < 0.0001). Complete relief from chest pain symptoms was observed in 12 patients (60%, p < 0.001), and 19 patients (95%) showed at least a one‐class improvement in the New York Heart Association functional class ( p < 0.0001). Conclusion This study is the first to incorporate AI guidance into PESA, demonstrating that this approach offers favorable safety and efficacy in the treatment of drug‐resistant HOCM. It effectively reduces left ventricular outflow tract obstruction and alleviates chest pain symptoms.