A Multicenter Randomized Controlled Trial of Echocardiography-Guided Atrial Septal Defect Closure Performed in a Mobile Surgical Unit

Overview

Cardiovascular disease remains a major threat to global health, and structural heart disease which encompassing congenital heart defects, valvular disease, and cardiomyopathies constitutes a substantial proportion of its burden. Atrial septal defect (ASD) is among the most common congenital heart conditions, occurring in approximately 1.6 per 1,000 live births. Percutaneous closure of ASD has become the standard treatment due to its minimally invasive nature and proven efficacy. However, conventional closure procedures rely heavily on fluoroscopic guidance and iodinated contrast, which carry risks of radiation exposure, contrast-related harm, and limit applicability in specific patient groups. Moreover, such procedures must be performed in catheterization laboratories equipped with digital subtraction angiography systems. To overcome these limitations, our team has spent over a decade developing a fully ultrasound-guided, radiation-free, contrast-free percutaneous intervention system-an original Chinese innovation that has pioneered "no incision, no fluoroscopy, and no general anesthesia" treatment for structural heart disease. This methodology has evolved into a comprehensive technical system and has been successfully applied to ASD, PFO, ventricular septal defect (VSD), patent ductus arteriosus (PDA), and several valvular disorders. It has been recognized by national clinical guidelines (2017), awarded the Chinese Medical Association First-Class Science and Technology Award (2022), and honored by the World Health Organization Innovation Award. Building upon the unique advantages of ultrasound-only guidance, we further developed a Mobile Surgical Vehicle. This mobile surgical unit integrates ultrasound imaging, sterilization, monitoring, and anesthesia equipment, enabling true "hospital-free" procedures for underserved regions lacking large medical devices. Early applications in remote areas of Southwest China and Belt-and-Road countries have demonstrated promising safety and feasibility. Nevertheless, high-quality clinical evidence evaluating this mobile platform for ASD closure is lacking. To address this gap, we propose a multicenter randomized controlled trial to demonstrate that mobile-platform ultrasound-guided closure is non-inferior to conventional in-hospital ultrasound-guided procedures. This study will also refine methodology, workflow, and safety protocols for mobile interventional therapy. Its findings will provide essential evidence supporting this original Chinese technology, expand its international impact, and enable broader access for patients in remote regions.

Interventions

• Other Mobile Surgical Vehicle Echocardiography-guided ASD closure Group
  Patients undergo ultrasound-guided percutaneous atrial septal defect closure performed inside a mobile surgical vehicle.
• Other Conventional Operating Room Echocardiography-guided ASD closure Group
  Patients undergo ultrasound-guided percutaneous atrial septal defect closure performed in a conventional operating room.

Primary outcome measures

• composite endpoint events [Time frame: at 30 days after the procedure]

Secondary outcome measures (9)

• failure of ultrasound-guided closure (conversion to fluoroscopy-guided intervention or open-heart surgery) [Time frame: immediately after the procedure]
• residual shunt >2 mm [Time frame: at 30 days after the procedure]
• device embolization or migration [Time frame: at 30 days after the procedure]
• new-onset arrhythmia [Time frame: at 30 days after the procedure]
• bleeding [Time frame: at 30 days after the procedure]
• infection [Time frame: at 30 days after the procedure]
• Composite endpoint events at 1 year [Time frame: at 1 year after the procedure]
• length of postoperative hospital stay [Time frame: at discharge (within 10 days after the procedure)]
• hospitalization costs [Time frame: at discharge (within 10 days after the procedure)]

Eligibility criteria

Inclusion criteria

• Patients ≥8 years and able to undergo percutaneous intervention under local anesthesia.
• Diagnosed with secundum ASD with a defect diameter of ≥6 mm and ≤36 mm, accompanied by right-sided volume overload.
• Anatomical features suitable for transcatheter closure: the distance from the defect rim to the coronary sinus, superior vena cava, inferior vena cava, and pulmonary veins is ≥5 mm; and the distance to the mitral valves is ≥7 mm.

Exclusion criteria

• Presence of primum ASD or sinus venosus ASD.
• Infective endocarditis or intracardiac thrombus.
• ASD with right-to-left shunting.
• Concomitant intracardiac anomalies requiring simultaneous surgical repair.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

China · 1 center

• Chinese Academy of Medical Sciences, Fuwai Hospital, Beijing — Beijing

Identifiers

NCT: NCT07273227 · 2024-2488

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗