Transapical Beating-Heart Septal Myectomy in Patients With Symptomatic Nonobstructive Hypertrophic Cardiomyopathy

Not Applicable

Recruiting

• Conditions: Nonobstructive Hypertrophic Cardiomyopathy

• Registration Number: NCT05952154
• Lead Sponsor: Xiang Wei

Brief Summary

The primary purpose of this study is to evaluate the feasibility, the safety and the efficacy of the transapical beating-heart septal myectomy for the treatment of nonobstructive hypertrophic cardiomyopathy. This is a prospective, single-arm, single-center study.

Detailed Description

Medical therapy is first recommended for patients with nonobstructive hypertrophic cardiomyopathy administrated at onset of heart failure symptoms. As the disease progresses, patients with global ejection fraction \< 50% should be evaluated with respect to eligibility and motivation for heart transplant. However, for those with preserved ejection fraction and drug-refractory heart failure symptoms, there is still no optimal therapy. Some patients with increased left atrial volume and/or diastolic dysfunction can be recognized as a result of excessive myocardial hypertrophy, and the septal resection for these patients may be beneficial. However, conventional septal myectomy is hindered by the demanding expertise that is needed to sufficient resection of hypertrophied septal myocardium while guarantee safety. To increase the visualization and minimize the surgical injury of conventional septal myectomy, we have invented a novel beating-heart myectomy device. Through a mini-thoractomy, septal myectomy could be accomplished via a transapical access in the beating heart using the beating-heart myectomy device. The whole process of resection is monitored, navigated, and evaluated by real-time transesophageal and transthoracic echocardiography. Left ventricular morphology and hemodynamics are evaluated each time after resection. Multiple resections are performed to tailor sufficient enlargement of left ventricular end-diastolic volume and improvement of mitral regurgitation, while preventing iatrogenic injuries. After transapical beating-heart septal myectomy, patients are scheduled to be seen for follow-up visits at discharge (about 7 days post operation) and 3 months.

Study Timeline

• Status Verified: 2023-07
• Study Start: 2023-07
• Study First Submitted: 2023-07-11
• Study First Submitted QC: 2023-07-11
• Last Update Submitted: 2023-07-11
• Study First Posted: 2023-07-19
• Last Update Posted: 2023-07-19
• Primary Completion: 2025-07
• Study Completion: 2025-07

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

1. Patients whose maximal ventricular septal wall thickness ≥ 15 mm.
2. Patients with heart function of New York Heart Association ≥ class II.
3. Patients with drug-refractory symptoms or intolerable to pharmaceutical therapies.
4. Patients who was informed the nature of the clinical trial, consented to participate in all of the activities of the clinical trial, and signed the informed consent form

Exclusion Criteria

1. Patients who were pregnant.
2. Patients who had concomitant diseases such as intrinsic valvular disease or coronary artery disease that needed open-heart surgery.
3. Patients who had severe heart failure with left ventricle ejection fraction < 40%.
4. Patients whose estimated life expectancy < 12 m.
5. Patient who were non-compliant.
6. Patients under circumstances which were considered not suitable or prohibitive for participating the clinical trial at the discretion of the attending medical team and the researchers.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
Procedural success	3 months	A reduction of ≥1 New York Heart Association (NYHA) class and a decrease of ≥ 20% of left atrial volume
All-cause mortality	3 months	Death from any cause during the observation period.

Secondary Outcome Measures

Name	Time	Method
Septal thickness	7 days and 3 months	Basal and mid septal thickness as measured by echocardiography.
Left atrial volume	7 days and 3 months	The left atria volume as measured by echocardiography.
New York Heart Association class	7 days and 3 months	New York Heart Association class, including grade I, grade II, grade III, grade IV. A higher grade means worse heart function.
Evaluation of the mitral valve	7 days and 3 months	Grade of mitral regurgitation and systolic anterior motion as measured by echocardiography.
Left ventricular end-diastolic volume	3 months	Left ventricular end-diastolic volume as measured by cardiac magnetic resonance.
Device success	1 day	Successful accession, delivery, and retrieval of the resection device, successful resection of the septal myocardium, mitral regurgitation (MR) ≤ grade 2+ during operation after resection, and free from conversion to midline thoracotomy during operation.
6-minute walking test	3 months	6-minute walking test. A longer distance means better heart function.
Left ventricle mass	7 days and 3 months	Left ventricle mass index (the ratio of left ventricle mass to body weight) as measured by cardiac magnetic resonance.
Major adverse cardiovascular and cerebral events	3 months	In-hospital mortality, atrioventricular block that need permanent pacemaker implantation, sternotomy conversion, iatrogenic ventricular septal perforation, iatrogenic valvular injury, imaging examination-validated cerebral complications.
Left ventricular outflow tract diameter	7 days and 3 months	Left ventricular outflow tract diameter as measured by echocardiography.
Heart function-associated quality of life	7 days and 3 months	Score of the Kansas City Cardiomyopathy Questionnaire. A higher score means better heart function.

Trial Locations

Locations (1)

Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology; 🇨🇳 Wuhan, Hubei, China