Pilot interventional randomized clinical trial to study the efficacy of left bundle branch pacing in patients with hypertrophic cardiomyopathy after myectomy for the prevention of progression of heart failure, prevent the occurrence of life-threatening rhythm disturbances and promote reverse remodeling of the LV. The aim of the study is to evaluate the comparative efficacy and safety of implantation of a cardioverter-defibrillator with left bundle branch block pacing and a dual-chamber cardioverter-defibrillator in patients with HCM and complete left bundle branch block after myectomy at high risk of SCD. Objectives of the study: 1. To analyze the safety of ICD implantation procedures with LBBB pacing in patients with HCM and LBBB after myectomy at high risk of SCD; 2. To develop a technique for LBBB lead implantation in patients with HCM and LBBB after myectomy; 3. To conduct a comparative analysis of QRS complex duration data based on ECG data before and after surgery, LV activation time, and pacing threshold based on postoperative programming data; 4. To conduct a comparative analysis of the functional class of CHF, NT-proBNP, the presence/absence of interventricular and intraventricular dyssynchrony, the degree of diastolic dysfunction, LVEF, and LV EDV based on echocardiography data before and 12 months after surgery; 5. Conduct a comparative analysis of QRS complex duration data based on ECG data, LV activation time, pacing threshold, the presence of recorded episodes of AF, VT, VF, antitachycardia and shock therapy according to programming data at 3, 6, and 12 months after surgery; 6. Assess quality of life before and 12 months after surgery using the KCCQ-12 questionnaire; 30 patients (15 patients in each group) will be randomly separated into 2 groups. All participants go through ICD programming at 3, 6, and 12 months after myectomy, assessment of left ventricular remodeling based on ECG and echocardiography, NT-proBNP, assessment of quality of life before surgery and 12 months after surgery.