Catheterization and Cardiovascular Interventions 84:471–472 (2014)
Editorial Comment Another Atrial Septal Occluder? Donald J. Hagler,* MD, FSCAI Professor of Pediatrics and Medicine, Divisions of Pediatric Cardiology and Cardiovascular Diseases, Mayo Clinic College of Medicine, Rochester, MN
Peirone et al. report the “Immediate and short-term ourcomes after percutaneous atrial septal defect closure R (pfm Medical, using the new Nit-Occlud ASD-R V Cologne,Germany), (NOASD-R) device” . This multiinstitutional study reports a prospective, single arm, observational study of 74 consecutive NOASD-R device closure of secundum atrial septal defects (ASD). While the authors seem to indicate that not all ASD device closure patients were included in the study, it is an excellent review of this initial experience. The usual selection criteria were reported with significant defects up to 28 mm in diameter, although there is little discussion concerning atrial rim adequacy. A Mullins type delivery sheath 1–2 mm larger than ASO requirement (12–14 Fr) is described. The reverse left atrial disc is attributed to minimize the risk of “pulling-through” the atrial septum, although apparently left and right pulmonary vein deployments were necessary in some cases. Several other features of the device are similar, such as nitinol frame, self-expandable, self-centering, low profile, recapturing, and repositioning. Additional unique features include 50% reduction in metal, premounting, and lack of pins or screws for attachment. Although, it is pointed out that the largest defect closed was 28 mm, a 30 mm device was used. The authors suspect that the 30 mm device may be too soft for some defects even though “reinforced rims” for the device are described. However, there is no mention of atrial defects without an aortic rim, or with a particular thick septum secundum or dilated aorta to encompass and possibly these defect were closed with other devices. There is no description of whether one would implant the device just touching the aorta or encompassing the aorta with absent aortic rim. One device was removed because of sudden development of complete heartblock. One apparently undersized device embolized to the aorta. Without pins or screws, a reported difficult retrieval ensued. Some of the device began to unravel, but it was successfully retrieved. One patient had atrial fibrillation during balloon sizing but long term arrhythmias were not found in the series. One C 2014 Wiley Periodicals, Inc. V
patient had a residual small defect and left to right shunt. We note, then, some of the usual complications but no late embolizations, cardiac perforations or erosions, wire fractures, endocarditis or death were observed in this small and short series. They point out that larger patient numbers and longer follow up is required to assess these concerns often related to chronic mechanical stress. So what new and of particular importance for ASD closure devices does this offer? Does the current device design make us confident that cardiac perforations and wall erosions will not occur with any of the current solid nitinol metal devices? By some estimates there have been at least 12–15 ASD closure device designs developed and six are no longer available because of device failure or reported complications. Clearly we need brilliant, innovative, engineers and entrepreneurs to help provide the best devices for safe and effective closure of the vast majority of secundum defects. This may mean more than one device and a variety of devices designed to treat a specific type of defect. The developers of the NOASD-R seem dedicated to developing a device with some unique design characteristics and are willing to pursue the appropriate studies to achieve regulatory approval with CE mark and FDA approval. The current device design may be another small step in achieving the goal of a better device. One can only hope that more manufacturers and developers will take on the task to clearly resolve the remaining concerns for device stability, safety (no erosions, heart block, and wire fractures), effective closure, and easy implantation in very large and or unusually shaped defects with absent aortic rims. This certainly is not likely to be the same type of device currently used but it seems that new device development will require innovative designs and study, computer modeling, and so forth, which would pre-emptively consider the problems of embolization, wall erosions and injuries to the cardiac conduction system. Bioabsorbable materials have been tested to a limited degree but would be another ideal method to achieve ASD device closure. Conflict of interest: Nothing to report. *Correspondence to: Donald Hagler, Mayo Clinic, Cardiovascular Diseases, Rochester MN. E-mail: [email protected]
Received 8 July 2014; Revision accepted 13 July 2014 DOI: 10.1002/ccd.25607 Published online 19 August 2014 in Wiley Online Library (wileyonlinelibrary.com)
Thus far, for bioabsorbable materials, concerns for a high incidence of persistent residual defects remain . So what will it take to eventually wind up with the safest and most effective device? It seems unlikely that one of the current devices will achieve that goal, but as noted in the study, larger number of patients and long term follow up will certainly be necessary to determine the real safety and effectiveness of the NOASD-R.
REFERENCES 1. Peirone A, Contreras A, Ferrero A, Nieckel da Costa, R, Pedra SF, Pedra CAC. Immediate and short-term outcomes after percutaneous atrial septal defect closure using the new Nit-Occlud ASD-R device. Catheter Cardiovasc Interv 2014;84:464–470. 2. Van de Branden, BJ, Post MC, Plokker HW, ten Berg, JM, Suttorp MJ. Patent foramen ovale closure using a bioabsorbable closure device. JACC Cardiovasc Interv 2010;3: 968–973.
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).