Hypertrophic Cardiomyopathy, Obstructive
Conditions
Keywords
Percutaneous Intramyocardial Septal Radiofrequency Ablation, children, hypertrophic cardiomyopathy
Brief summary
The primary purpose of this study was to demonstrate the safety and efficacy of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) in children and assessed its performance and functional outcomes in the follow-up. This is a single-arm, single-center study.
Detailed description
The prevalence of hypertrophic cardiomyopathy (HCM) ranks second among cardiomyopathies in children. The prognosis of HCM has been previously demonstrated to be closely correlated with age. HCM in childhood is frequently associated with severe symptoms and high mortality rates, exhibiting a 36% higher incidence of malignant ventricular arrhythmias compared to adults, and being twice as likely to necessitate advanced heart failure therapies such as heart transplantation or left heart assist devices. Surgical septal myectomy can effectively help patients with drug-refractory symptoms but carries risks inherent to invasive procedures and requires expertise that is not universally available. Alcohol septal ablation is not recommended for applications in the young patient group. Percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) is a new method for the treatment of HCM using a special diagnosis and treatment device on the target area of the heart under the guidance of echocardiography. The method breaks through the worldwide problem of minimally invasive treatment of the myocardium on the beating heart, thus avoiding X-ray radiation and contrast agent damage. Previous research has illustrated the effectiveness and safety of PIMSRA for adult patients with obstructive HCM. We have found that PIMSRA results in sustained improvement in exercise capacity, persistent reduction in left ventricle outflow tract (LVOT) gradient, and sustained improvement in cardiac function. This is an early feasibility study to evaluate the clinical safety and efficacy of PIMSRA in pediatric patients, as well as to assess postoperative cardiac function and exercise capacity.
Interventions
Percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) is an innovative minimally invasive ablation treatment. Under the real-time transthoracic echocardiography guidance, a radiofrequency electrode needle is introduced into the hypertrophied interventricular septum via the percutaneous intramyocardial approach. Then the needle tip is pushed to the target region of the interventricular septal (IVS) basal segment 8 to 10 mm from the subaortic valve. The main objective of PIMSRA is to reduce ventricular septal hypertrophy and left ventricular outflow tract obstruction by means of thermal ablation.
Sponsors
Xijing Hospital
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
No minimum to 18 Years
Healthy volunteers
No
Inclusion criteria
* Clinical diagnosis of hypertrophic obstructive cardiomyopathy * Age younger than 18 years * Resting or provoking left ventricular outflow tract gradient ≥ 50 mmHg * Drug-refractory symptoms or intolerable to pharmaceutical therapies * Heart function of New York Heart Association ≥ class II
Exclusion criteria
* Secondary left ventricular hypertrophy (LVH) related to subaortic stenosis or aortic stenosis * Presence of concomitant heart disease requiring surgery * Left ventricular ejection fraction \<40% * Cardiac resynchronization therapy within 3 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Safety composite outcome | 30 days | The number of people who reach the composite safety outcome (the occurrence of at least one) of the following measured variables: 1) all-cause death; 2) heart failure; 3) ventricular fibrillation. |
| Feasibility outcome | 6 months | The proportion of patients with a peak left ventricle outflow tract gradient lower than 30 mmHg. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Major surgery-related adverse events | 30 days | Emergency surgery, severe pericardial tamponade, conduction block due to deviation in ablation range, surgery related ventricular septal perforation, stroke and malignant arrhythmias. |
| LVOT gradient | through study completion, an average of 2 years | Left ventricular outflow tract gradient as measured by echocardiography. |
| Maximum interventricular septal thickness | through study completion, an average of 2 years | Maximum septal thickness as measured by echocardiography. |
| New York Heart Association functional scale | through study completion, an average of 2 years | New York Heart Association class, including grade I, grade II, grade III, grade IV. A higher grade means worse heart function. |
Countries
China
Contacts
PRINCIPAL_INVESTIGATORLiwen Liu, Ph.D, M.D.
Xijing Hospital
Outcome results
None listed