Recent development of transcatheter closure of atrial septal defect and patent foramen ovale with occluders

A Prospective, Single-Center, Phase I Clinical Trial to Evaluate the Value of Transesophageal Echocardiography in the Closure of Patent Foramen Ovale With a Novel Biodegradable Occluder

Objective

Traditional metal alloy occluders for the closure of patent foramen ovale (PFO) may be associated with some potential complications, and may restrict the trans-septal access to the left atrium for future treatment of left-sided heart disease. Increasing attention has been paid to novel biodegradable occluders (NBOs) to achieve PFO closure. We aimed to evaluate the role of transesophageal echocardiography (TEE) in the diagnostic and anatomical evaluation of PFO, as well as in the Post-procedural assessment after transcatheter closure with a NBO.

Methods

We conducted a prospective, single-center clinical study of 44 patients who were diagnosed with PFO by contrast transthoracic echocardiography (c-TTE) and TEE from June 2019 to June 2020. All patients underwent PFO occlusion with NBO under TTE guidance. Follow-up was performed at 2 days and 3 months after the procedure with TTE, and at 6 months and 1 year after the procedure with c-TTE, TTE, and TEE.

Results

Interventional treatment was successfully performed in all patients. The left and right sides of the occluder device disc were significantly reduced at 3, 6, and 12 months compared to 2 days after the procedure (all P < 0.01), and decreased gradually. The thickness was significantly reduced at 12 months compared to the first three time points (all P < 0.01). Thrombus was found on the surface of the occluder device in three patients (6.4%) at 3 and 6 months after occlusion. At 6 months after procedure, there were 3 (6.8%) cases of extensive residual right-to-left shunt (RLS), 2 (4.5%) cases of moderate shunt, and 7 (15.9%) cases of small shunts. One year after procedure, 2 (4.5%) cases had a extensive residual shunt, 6 (13.6%) cases of small shunts were confirmed to originate from pulmonary veins by TEE, and the PFO-RLS occlusion rate reached 95.5%.

Conclusion

This study demonstrates the feasibility, safety, and effectiveness of NBO for the closure of PFO in humans, with a high rate of complete shunt closure. Accurate TEE assessment of the PFO anatomy before closure with NBO is important to ensure that the procedure remains safe and effective. Furthermore, TEE plays a crucial role in the Post-procedure follow-up.

Health-Related Quality of Life in Children and Adolescents with Simple Congenital Heart Defects before and after Transcatheter Intervention Therapy: A Single-Center Study

Objective: To explore the health-related quality of life (HRQoL) of children and adolescents with simple congenital heart defects before and after the transcatheter intervention.

Methods: The Pediatric Quality of Life Inventory 4.0 scale was used to assess the quality of life of 78 children and adolescents before and after the transcatheter intervention and to evaluate the parents’ perception of their children’s quality of life.

Results: In all, 76 patients were completed the study. The results showed that the scores of the four dimensions and the total score for the quality of life of the patients significantly improved 1 month after the intervention. At 6 months after treatment, the scores in all dimensions continued to improve. From the parents’ perspective, the scores of the patients in all dimensions improved significantly at 1 month and 6 months after treatment. In terms of the quality of life assessment, the self-assessment results of the patients were more positive than those of their parents.

Conclusions: The results showed that the quality of life of children and adolescents with simple congenital heart defects can be positively affected by the transcatheter intervention. Moreover, this improvement is not transient and seems to increase over time.

Key Regulatory Differentially Expressed Genes in the Blood of Atrial Septal Defect Children Treated With Occlusion Devices

Atrial septal defects (ASDs) are the most common types of cardiac septal defects in congenital heart defects. In addition to traditional therapy, interventional closure has become the main treatment method. However, the molecular events and mechanisms underlying the repair progress by occlusion device remain unknown. In this study, we aimed to characterize differentially expressed genes (DEGs) in the blood of patients treated with occlusion devices (metal or poly-L-lactic acid devices) using RNA-sequencing, and further validated them by qRT-PCR analysis to finally determine the expression of key mediating genes after closure of ASD treatment. The result showed that total 1,045 genes and 1,523 genes were expressed differently with significance in metal and poly-L-lactic acid devices treatment, respectively. The 115 overlap genes from the different sub-analyses are illustrated. The similarities and differences in gene expression reflect that the body response process involved after interventional therapy for ASDs has both different parts that do not overlap and the same part that crosses. The same portion of body response regulatory genes are key regulatory genes expressed in the blood of patients with ASDs treated with closure devices. The gene ontology enrichment analysis showed that biological processes affected in metal device therapy are immune response with CXCR4 genes and poly-L-lactic acid device treatment, and the key pathways are nuclear-transcribed mRNA catabolic process and proteins targeting endoplasmic reticulum process with ribosomal proteins (such as RPS26). We confirmed that CXCR4, TOB1, and DDIT4 gene expression are significantly downregulated toward the pre-therapy level after the post-treatment in both therapy groups by qRT-PCR. Our study suggests that the potential role of CXCR4, DDIT4, and TOB1 may be key regulatory genes in the process of endothelialization in the repair progress of ASDs, providing molecular insights into this progress for future studies.

Biodegradable atrial septal defect occluders: A current review

Atrial septal defect (ASD) is a common structural congenital heart disease. With the development of interventional closure devices and transcatheter techniques, interventional closure therapy has become the most well-accepted therapeutic alternative worldwide, as it offers a number of advantages over conventional therapies such as improved safety, easier operation, lower complication rates and invasiveness, and shorter anesthetic time and hospitalizations. During the past decades, various types of occluders based on nondegradable shape memory alloys have been used in clinical applications. Considering that the permanent existence of foreign nondegradable materials in vivo can cause many potential complications in the long term, the research and development of biodegradable occluders has emerged as a crucial issue for interventional treatment of ASD. This review aims to summarize partially or fully biodegradable occlusion devices currently reported in the literature from the aspects of design, construction, and evaluation of animal experiments. Furthermore, a comparison is made on the advantages and disadvantages of the materials used in biodegradable ASD occlusion devices, followed by an analysis of the problems and limitations of the occlusion devices. Finally, several strategies are proposed for future development of biodegradable cardiac septal defect occlusion devices. STATEMENT OF SIGNIFICANCE: Although occlusion devices based on nondegradable alloys have been widely used in clinical applications and saved numerouspatients, biodegradable occlusion devices may offer some advantages such as fewer complications, acceptable biocompatibility, and particularly temporary existence, thereby leaving "native" tissue behind, which will certainly become the development trend in the long term. This review summarizes almost all partially or fully biodegradable occlusion devices currently reported in the literature from the aspects of design, construction, and evaluation of animal experiments. Furthermore, a comparison is made on the advantages and disadvantages of the materials used in biodegradable ASD occlusion devices, followed by an analysis of the problems and limitations of the occlusion devices. Finally, several strategies are proposed for future development of biodegradable cardiac septal defect occlusion devices.

Atrial septal defect (ASD) device trans-catheter closure: limitations

Transcatheter closure is a widespread technique used to treat secundum atrial septal defects (ASDs). When compared to surgery, it provides a less invasive approach with quicker recovery and reduced physical and psychological impact. Nowadays, almost 85-90% of all secundum ASD can be closed by using a transcatheter approach. However, several limitations may have a significant impact on the feasibility and success of percutaneous ASD closure. Limitations can be grouped as: (I) anatomical; (II) device-related; (III) associated defects and natural history associated issues; (IV) physiological; (V) complications. Physician should be aware of potential limits of percutaneous ASD closure.

Improvement of physical capacity in patients undergoing transcatheter closure of atrial septal defects

INTRODUCTION

Atrial septal defect (ASD) is the most common congenital cardiac anomaly diagnosed in adults. It often remains asymptomatic until the fourth or fifth decade of life. Significant left-to-right interatrial shunting is associated with the risk of heart failure, pulmonary hypertension and atrial fibrillation. Percutaneous ASD closure is a recognized method of treatment.

AIM

To evaluate the clinical outcomes and physical capacity in patients undergoing transcatheter closure of ostium secundum ASD.

MATERIAL AND METHODS

One hundred and twenty adult patients (75 females and 45 males) with a mean age of 43.1 ±13.3 (17-78) years who underwent transcatheter device closure of ostium secundum ASD were analyzed. Clinical evaluation and transthoracic color Doppler echocardiographic study were repeated in all patients before as well as 1 and 24 months after the procedure. To assess the physical capacity symptom-limited treadmill exercise tests with respiratory gas-exchange analysis were performed in all patients before the procedure and after 24 months of follow-up.

RESULTS

The devices were successfully implanted in all patients. During 24 months of follow-up all patients showed significant clinical and spiroergometric improvement of exercise capacity, and a significant decrease of right heart chamber overload features on echocardiography.

CONCLUSIONS

Transcatheter closure of ASD in patients with significant shunt resulted in significant clinical and hemodynamic improvement regardless of the baseline functional class.