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Updated: Oct 19, 2025
Echocardiographic Evaluation of Atrial Communications before Transcatheter Closure
Published on: February 8, 2022
Angioscopic Evaluation of Atrial Septal Defect Closure Device Neo-Endothelialization
Yasuhiro Tanabe1, Tomomi Suzuki1, Shingo Kuwata1
1Division of Cardiology Department of Internal Medicine St. Marianna University School of Medicine Kanagawa Japan.
Insights
Neo-endothelialization of septal occluder devices after transcatheter closure of atrial septal defect varies significantly. Poor endothelialization and thrombus formation were linked to larger devices and central areas six months post-implantation.
Area of Science:
- Cardiology
- Interventional Cardiology
- Biomaterials
Background:
- Current guidelines suggest 6 months of antithrombotic therapy and antibiotic prophylaxis post-device closure for atrial septal defects.
- Complete neo-endothelialization of septal occluders is estimated to take 6 months.
- In vivo human assessment of neo-endothelialization has not been previously performed.
Purpose of the Study:
- To evaluate the in vivo neo-endothelialization of septal occluder devices six months after transcatheter atrial septal defect closure in humans.
- To assess the relationship between device size, endothelialization, and thrombus formation.
Main Methods:
- Angioscopy from the right atrium was used to evaluate neointimal coverage of septal occluder devices in 15 patients at 6 months post-implantation.
- Occluder surfaces were divided into 9 areas and endothelialization was semiquantitatively graded.
- Patients were categorized into good (average grade score ≥2) and poor (average grade score <2) endothelialization groups.
Main Results:
- Six-month neo-endothelialization was sufficient in two-thirds of patients and insufficient in one-third.
- Poor endothelialization was associated with larger deployed devices (27.0 mm vs. 17.0 mm) and progressive right heart dilatation.
- Thrombus formation was significantly higher in poorly endothelialized areas (Grade 0: 94.1%) compared to well-endothelialized areas (Grade 3: 1.6%).
- Endothelialization was notably poorer in the central areas of the devices.
Conclusions:
- Neo-endothelialization on septal occluder devices shows significant variability at 6 months post-implantation.
- Larger device size and central device areas are associated with poorer endothelialization and increased thrombus attachment.
- Findings suggest potential implications for current antithrombotic therapy guidelines.
Abstract:
Background Current guidelines recommend at least 6 months of antithrombotic therapy and antibiotic prophylaxis after septal-occluding device deployment in transcatheter closure of atrial septal defect. It has been estimated that it takes ≈6 months for complete neo-endothelialization; however, neo-endothelialization has not previously been assessed in vivo in humans. Methods and Results The neointimal coverage of septal occluder devices was evaluated 6 months after implantation in 15 patients by angioscopy from the right atrium. Each occluder surface was divided into 9 areas; the levels of endothelialization in each area were semiquantitatively assessed by 4-point grades. Device neo-endothelialization was sufficient in two thirds of patients, but insufficient in one third. In the comparison between patients with sufficiently endothelialized devices of average grade score ≥2 (good endothelialization group, n=10) and those with poorly endothelialized devices of average grade score <2 (poor endothelialization group, n=5), those in the poor endothelialization group had larger devices deployed (27.0 mm [25.0-31.5 mm] versus 17.0 mm [15.6-22.5 mm], respectively) and progressive right heart dilatation. The endothelialization was poorer around the central areas. Moreover, the prevalence of thrombus formation on the devices was higher in the poorly endothelialized areas than in the sufficiently endothelialized areas (Grade 0, 94.1%; Grade 1, 63.2%; Grade 2, 0%; Grade 3, 1.6%). Conclusions Neo-endothelialization on the closure devices varied 6 months after implantation. Notably, poor endothelialization and thrombus attachment were observed around the central areas and on the larger devices.
