Current practice in atrial septal defect occlusion in children and adults

INTRODUCTION

Atrial septal defect (ASD) is one of the most common congenital heart diseases (CHD) in children and adults. This group of malformations includes several types of atrial communications allowing shunting of blood between the systemic and the pulmonary circulations. Early diagnosis and treatment carries favorable outcomes. Patients diagnosed during adulthood often present with complications related to longstanding volume overload such as pulmonary artery hypertension (PAH), atrial dysrhythmias, and right (RV) and left (LV) ventricular dysfunction.

AREA COVERED

This article intended to review all aspects of ASD; anatomy, pathophysiology, clinical presentation, natural history, and indication for treatment. Also, we covered the transcatheter therapy in detail, including the procedural aspect, available devices, and outcomes.

EXPERT OPINION

There has been a remarkable improvement in the treatment strategy of ASD over the last few decades. Transcatheter closure of ASD is currently accepted as the treatment of choice in most patients with appropriately selected secundum ASDs. This review will focus on the most recent advances in diagnosis and treatment strategy of secundum ASD.

Developing High Medical Technology, a Challenge for Developing Countries: The Percutaneous Closure of Atrial Septal Defects Using Nit-Occlud ASD-R: Early and Mid-term Results

Objective:

To assess the efficacy and safety of the Nit-Occlud ASD-R (PFM S.R.L, La Paz, Bolivia) in the percutaneous closure of secundum atrial septal defects (ASD).

Patients and Methods:

Fifty-three consecutive patients with median age of 11 years (range 3-67) and mean weight 27.1 kg (range 13-75 kg), treated in two cardiology centers between May 2007 and March 2011.

Results:

Mean fluoroscopy time was 14 minutes (5-53), mean procedure time was 70 minutes (45-150), mean defect size, as measured by the stop-flow technique, was 17.8 mm (5.6-31), and mean stent size of the implanted device was 18 mm (6-28), which is 0.98 times the defect size. Successful closure of the ASD without major complications was achieved in 49 of 53 patients. In 71.4% of patients in whom device implantation was accomplished, there was no evidence of a persistent shunt at the completion of the procedure. This closure rate increased to 91.7% after 24 hours, with 95.8% closure after three months and 100% closure after six months. Device embolization occurred in one patient within 24 hours of implantation and required surgical device removal and ASD closure. There were no other major complications and no deaths during the period of follow-up (average 72 months; range 59-105 months).

Conclusion:

The Nit-Occlud ASD-R device is safe and effective with very good closure rates.

Transcatheter closure of atrial septal defect: principles and available devices

There has been a remarkable improvement in the treatment strategy of secundum atrial septal defect (ASD) over the last few decades. Indebted to the improvement in device technology and procedural techniques, transcatheter closure of ASD is currently accepted as the treatment of choice in most patients with secundum ASD. Recent generation devices enable easy and safe deployment of device with the properties of adequate flexibility, re-capturability and repositioning. Use of biocompatible materials with improved device design and refined equipment finish may promote re-endothelialization and reduce potential damage to nearby structures. Most of currently available devices show excellent efficacy and comparable outcome with its own advantages and disadvantages. In addition to improvement of device properties and performance, there has been distinct improvement in procedural technique from numerous experiences of device closure of ASD. Nowadays there are well established principles regarding patient selection, pre-procedural evaluation, step-by-step details of procedure as well as post-procedural follow-up. However, an operator may encounter pitfalls in closing complex lesions such as large defect, rim deficiencies and multiple defects, so every operator has to be familiar with each available device, general principle as well as special issues for complex lesions.

Techniques for trans-catheter retrieval of embolized Nit-Occlud® PDA-R and ASD-R devices

BACKGROUND

Nit-Occlud^® (atrial septal defect) ASD-R and (patent ductus arteriosus) PDA-R devices are used outside the United States for percutaneous closure of the patent ductus arteriosus and atrial septal defects. When embolization occurs, these devices have been difficult to retrieve.

METHODS

Bench simulations of retrieval of PDA-R and ASD-R devices were performed in a vascular model. Retrieval of each device was attempted using snare techniques or with bioptome forceps with a range of devices. The same devices were then intentionally embolized in an animal model. Retrieval methods were systematically tested in a range of sheath sizes, and graded in terms of difficulty and retrieval time.

RESULTS

Devices that were grasped by the bioptome in the center of the proximal part of the devices were easily retrieved in both models. Bench studies determined the minimum sheath sizes needed for retrieval of each device with this method. In general sheathes two french sizes greater than the delivery sheath were successful with this technique. Three out of the four PDA-R devices were successfully retrieved in vivo. Two were retrieved by grasping the middle of the PA end of the PDA-R device with a Maslanka bioptome and one small PDA-R device was retrieved using a 10 mm Snare. Four of the five ASD-R devices were retrieved successfully grasping the right atrial ASD-R disc or by passing a wire through the device and snaring this loop. For ASD-R 28 and 30 mm devices, a double bioptome technique was needed to retrieve the device.

CONCLUSION

ASD-R and PDA-R devices can be successfully retrieved in the catheterization lab. It is critical to grab the center portion of the right atrial disc of the ASD-R device or pulmonary portion of the PDA-R device and to use adequately sized sheathes.

Initial Experience with the Nit-Occlud ASD-R: Short-Term Results

We aim to assess the safety, feasibility and efficacy of the new Nit-Occlud ASD-R (NOASD-R) device. From 2014 to 2015, transcatheter closure of atrial septal defect (ASD) using the NOASD-R was performed in 30 consecutive patients. The standard deployment technique as the left upper pulmonary vein approach was used in 25 patients. Right upper pulmonary vein approach was required in five. The median age was 6 years (range 3.5-60 years), and median weight was 21.5 kg (14-79 kg). Implantation was successful in all patients. The median size of devices was 16 mm (12.0-26.0 mm). The mean device size/2D defect diameter ratio was 1.26 ± 0.09 (1.12-1.40). The mean device size/color flow diameter ratio was 1.07 ± 0.06 (range 1.0-1.22). Releasing problem was encountered in three patients. A device-related erosion on the day after the closure was observed in one patient. No further device-related complication (erosion, embolization or dislodgement of the device) was encountered in a median follow-up period of 10 months (range 2-14 months). Complete occlusion has occurred in all at follow-up. NOASD-R is a feasible and effective device for use in the transcatheter occlusion of moderate to large secundum ASDs in selected patients. The occurrence of the erosion on the right atrial roof may be due to the high localization of the device and the larger size of the right disk.

Historical developments of atrial septal defect closure devices: what we learn from the past

INTRODUCTION

Since King and Mills' pioneering work in percutaneous closure devices of secundum atrial septal defects (ASD) four decades ago, developments in device shape, material and implantation technique led to adoption of percutaneous ASD closure as current treatment of choice. Not only was the feasibility of such a percutaneous procedure tested altogether, but pursuing the ideal device in terms of safety and efficacy became priority.

AREAS COVERED

In this review we present the historical development of ASD devices in design, material and technique with clinical data, and provide the future perspectives in percutaneous ASD closures.

EXPERT OPINION

An 'ideal device' requires complete defect closure with negligible risk of complications using a safe, straightforward delivery technique with repositioning and retrieving properties. Some of the devices currently at hand come close to fulfilling these criteria, however none seem to provide those prerequisites completely. By understanding how challenges in device development were overcome in the past, new insights into future improvements are given.

Feasibility, Safety and Long-Term Follow-Up of Transcatheter Closure of Secundum Atrial Septal Defects with Deficient Rims

Objective: The aim of this work was to evaluate the feasibility and safety of transcatheter closure procedures for the treatment of atrial septal defects (ASDs) with insufficient rims. Methods: A total of 507 secondary ASDs were divided into two groups based on whether they had deficient rims or not (152 vs. 355 cases, respectively). Any complications, including residual shunt, heart arrhythmia, occluder translocation, etc., were followed up for 1-3 years. Results: There were no differences in gender, weight, exposure time, ECG states, pulmonary pressure, the intervention success rate, occurrence of residual shunt, the operation time and occurrence of residual shunt during follow-up between the two groups (p > 0.05). However, the occurrence of rhythm disorders was significantly different between the two groups; ASDs with deficient rims were at an elevated risk (p < 0.05). Specifically, there was a significantly higher incidence in the occurrence of arrhythmia in the deficient rims group at 24 h postoperation, but no differences in arrhythmia incidence at any of the other follow-up time points (1, 3, 6, 12 and 36 months; p > 0.05). Conclusions: Patients with deficient rims experience a high success rate of ASD intervention and low rate of complications when the procedures are performed by experienced operators.