A Clinical Study of Precision Chemoablation for Hypertrophic Obstructive Cardiomyopathy Without Large Interventricular Septal Branches

OBJECTIVE: This study aims to evaluate the clinical efficacy and safety of ultrasound-guided percutaneous septal precision chemical ablation in the treatment of hypertrophic obstructive cardiomyopathy (HOCM). METHODS: From December 2020 to July 2024, 27 patients with HOCM without large target septal branches (diffuse multiple branches, all less than 1 mm in diameter) were enrolled and underwent ultrasound-guided percutaneous septal chemical ablation. Intraoperative left ventricular outflow tract gradient (LVOTG), postoperative cardiac troponin I (cTnI), complications, and changes in the 36-Item Short Form Survey (SF-36) score, New York Heart Association (NYHA) functional classification and echocardiography parameters in 1 year post-PTSMA were monitored and analyzed. RESULTS: Immediate postoperative LVOTG values monitored by catheter and echocardiography were both significantly decreased (both p < 0.05) in the 27 patients, whereas the cTnI level was increased after PTSMA treatment (p < 0.05). One patient developed transient complete right bundle branch block during the procedure. At the 1-year follow-up, these patients showed significantly increased scores in all the eight domains of the SF-36 scale, and markedly improvement in echocardiography-based LVOTG value (p < 0.05) and NYHA functional classification (p < 0.05). However, no significant change were observed in the mean interventricular septal thickness (IVSTh) and left ventricular ejection fraction (LVEF) before and after operation (p > 0.05). CONCLUSION: Ultrasound-guided precision PTSMA with gelatin sponge is a safe and effective treatment approach for HOCM patients, which can reduce the left ventricular outflow tract obstruction and greatly improve the life quality of the patients.