title: Nickel elution properties of contemporary interatrial shunt closure devices.
abstract: OBJECTIVE
  We sought to compare nickel elution properties of contemporary interatrial shunt closure devices in vitro.
  
  
  BACKGROUND
  There are two United States Food and Drug Administration (FDA)-approved devices for percutaneous closure of secundum atrial septal defect: the Amplatzer septal occluder (ASO; St Jude Medical Corporation) and Gore Helex septal occluder (HSO; W.L. Gore & Associates). The new Gore septal occluder (GSO) device is in clinical trials. These are also used off-label for patent foramen ovale closure in highly selected patients. These devices have high nickel content. Nickel allergy is the most common reason for surgical device explantation. Nickel elution properties of contemporary devices remain unknown.
  
  
  METHODS
  We compared nickel elution properties of 4 devices - ASO, GSO, HSO, and sternal wire (SW) - while Dulbecco's phosphate-buffered saline (DPBS) served as control. Three samples of each device were submerged in DPBS. Nickel content was measured at 14 intervals over 90 days.
  
  
  RESULTS
  Nickel elution at 24 hours, compared to control (0.005 ± 0.0 mg/L), was significantly higher for ASO (2.98 ± 1.65 mg/L; P=.04) and SW (0.03 ± 0.014 mg/L; P=.03). Nickel levels at 90 days, compared to control (0.005 ± 0.0 mg/L) and adjusting for multiple comparisons, were significantly higher for ASO (19.80 ± 2.30 mg/L; P=.01) and similar for HSO (P=.34), GSO (P=.34), and SW (P=.34). ASO had significantly higher nickel elution compared to HSO, GSO, and SW (P=.01).
  
  
  CONCLUSIONS
  There is substantial variability in nickel elution; devices with less exposed nickel (HSO and GSO) have minimal elution. The safety of low nickel elution devices in patients with nickel allergy needs to be evaluated in prospective trials.
authors: Division of Cardiovascular Medicine, University of Utah School of Medicine, 50 North Medical Drive, Suite 4A100 SOM, Salt Lake City, UT 84132 USA. div.verma@hsc.utah.edu.
authors: Divya Ratan
authors: DR
authors: Verma
authors: Muhammad F
authors: MF
authors: Khan
authors: Anwar
authors: A
authors: Tandar
authors: Namakkal S
authors: NS
authors: Rajasekaran
authors: Renée
authors: R
authors: Neuharth
authors: Amit N
authors: AN
authors: Patel
authors: Joseph B
authors: JB
authors: Muhlestein
authors: Rodney S
authors: RS
authors: Badger
mesh_terms: D006328:Cardiac Catheterization / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible; D017548:Echocardiography, Transesophageal; D005500:Follow-Up Studies; D054092:Foramen Ovale, Patent / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D009532:Nickel; D011474:Prosthesis Design; D012189:Retrospective Studies; D055989:Septal Occluder Device; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible; D009532:Nickel