This single-center, prospective, open-label, randomized, controlled clinical trial is designed to assess the efficacy and safety of the Thoracoscopic Morrow procedure in the treatment of hypertrophic obstructive cardiomyopathy. The primary objectives include investigating:

Question 1: The efficacy and safety of two surgical modalities in patients presenting with left ventricular outflow tract obstruction and mid-left ventricular hypertrophy.

Question 2: The impact of the two surgical procedures on hemodynamics in patients with left ventricular outflow tract obstruction, mid-left ventricular obstruction, and in individuals with or without organic valvular lesions.

Question 3: The effects of the two surgical procedures on exercise capacity, quality of life, and long-term prognosis among patients with left ventricular outflow tract obstruction and central left ventricular obstruction, both with and without valvular lesions.

Participants will be stratified into two groups. The experimental group will undergo thoracoscopic Morrow surgery, while the control group will undergo median open modified enlarged Morrow surgery.

This study is a single-center, prospective, open-label, randomized, controlled trial designed to investigate the therapeutic value of thoracoscopic Morrow procedure in patients with hypertrophic obstructive cardiomyopathy (HOCM). The study focuses on HOCM patients, with the modified extended Morrow procedure via median sternotomy considered as the 'gold standard treatment' in the control group. The objective is to explore the efficacy of the thoracoscopic Morrow procedure in improving exercise tolerance in HOCM patients, assess the short-term and long-term effectiveness, safety, as well as changes in cardiac function, cardiac structure, and myocardial fibrosis levels associated with thoracoscopic Morrow procedure in treating obstructive HOCM.

Inclusion Criteria:

• diagnosed with hypertrophic cardiomyopathy (HCM);
• age ≥18 years old;
• presence of left ventricular outflow tract/mid-ventricular obstruction, with a resting left ventricular outflow tract pressure gradient/left ventricular cavity pressure gradient ≥50 mmHg; significant symptoms persist despite optimal medical therapy, and surgical evaluation indicates the need for intervention;
• left ventricular ejection fraction (LVEF) ≥55%;
• signed informed consent, willing and able to return to the hospital for follow-up.

Exclusion Criteria:

• previously underwent septal reduction therapy (including surgical or interventional procedures);
• received or planning to receive an implantable cardioverter-defibrillator (ICD) in the past 3 months;
• individuals with concomitant conditions requiring simultaneous surgical intervention;
• New York Heart Association (NYHA) functional class IV;
• unwilling to undergo surgical treatment;
• pregnant or lactating or planning pregnancy;
• previously participated in other clinical trials before enrollment;
• individuals with concurrent diseases with an expected lifespan of less than 1 year.