Transcript Nickel toxicity: what is the issue?

Kurt Amplatz MD
University of Minnesota Hospital and
Clinics Minneapolis, MN
presents
Recorded at the 3rd Pediatric
Interventional Cardiac Symposium,
September 1999, in Chicago, Illinois.
Nickel toxicity: what is the issue?
Société Française de Cardiologie
Conclusions: CardioSEAL
1. no nickel
2. less bulky
3. better endothelialization
CardioSEAL metal
The metal of our competitor is MP35N
with a 33% nickel content!
Amplatzer® devices
from Felix Berger MD
Fig. 1
Implanted high-profile Amplatzer devices
Nickel allergy
Nine percent of the population is
allergic to nickel. However implantation
of nickel-containing prostheses and
devices virtually never causes
problems.
Allergy and
nickel-containing implants
Dear Dr. Amplatz,
Many thanks for answering about percutaneous closure
of ASD with the Amplatzer device in patients with allergy
to nickel. As you know, I decided to perform the
procedure in this young lady that presented with a
cutaneous allergic reaction to nickel: The procedure was
uneventful and at one month follow-up, no shunt was
detected by Echo and she is doing fine…
Eustaquio Onorato MD
Clinica San Rocco Di Franciacorta SpA
Ome, Italy
An essential element
Nickel is an essential element for
nutrition. Lack of nickel results in
retarded body growth, anemia, and
increased neonatal mortality in
experimental animals.
Inorganic elements essential for life:
Cu, Zn, Se, Mg, Mn, Ca, Fe, Mo, Ni, etc
Toxicity
Paracelsus (1493–1541): The factor
determining whether a compound is
toxic or not depends on the dose
Intake of nickel
Daily intake of nickel in the United
States ranges from 300 to 600
micrograms per day.
Most of the ingested nickel is
excreted via feces, urine, bile, and
sweat.
Exposure to nickel
Nickel-containing alloys used in:
coins (quarters, nickels, euros)
knives, forks, spoons, etc
implants: wires, clips, coils,
stents, nails, cava filters,
prostheses, heart valves,
pacemakers, etc
Anodic corrosion test
Fig. 2 Nitinol wire corroded by anodic dissolution for 2 minutes at 6
mA. Pits and corrosion products are obvious.
Explanted orthodontal arch wires
Control
Explanted wire
Fig. 3 Nitinol arch wire explanted at 1 month shows no evidence of
corrosion.
Implanted Amplatzer devices
Amin Z, et al. Circulation 1999;100:320-328
Fig. 4 Amplatzer devices implanted in a dog with 2 ventricular
septal defects. The second device is a "dog-bone" design that was
investigated in some animals.
Follow-up at 1 week
Fig. 5 One week after implantation, there is complete closure of the
communication.
Follow-up at
1, 14, and 18 months
Fig. 6 At one-month follow-up, there is no change. Inspection at 14
and 18 months (not shown) confirms the same and demonstrates no
aortic or tricuspid insufficiency.
Cardioscopy of right disks
First device
Second device
Fig. 7 Right side of the device is completely endothelialized.
Cardioscopy of
the left disks and valves
Fig. 8 Left side of the device shows complete endothelialization,
except of the post. Cardioscopy, in other views (not shown),
confirms normal aortic, mitral, and tricuspid valves.
Explanted Amplatzer devices
First device
Second device
Fig. 9 Amplatzer devices, explanted at 18 months and polyester fabric
removed, are indistinguishable from brand-new devices. There is not a
single wire broken.
Human experience
Masura J, et al. Cathet Cardiovasc Diagn 1997;42:388-393
September 1995: first implant in a
patient
November 1998: device is intact and
shows only total heart motion
Nickel toxicity
Nickel toxicity occurs exclusively in
nickel refineries due to inhalation of
nickel carbonyl, Ni(CO)4, being part of
the Mond process.
Explanted devices
under light microscopy
Fig. 10 The explanted Amplatzer devices under light microscopy
reveal a perfectly shiny surface with no evidence of pitting.
Explanted devices
under scanning electromicroscopy
End disk
Disk with female screw
Fig. 11 Scanning electromicroscopy again reveals no corrosion of
the explanted devices.
Explanted devices
at x3000 magnification
Control
Explanted wire
Fig. 12 At x3000 magnification, the explanted Amplatzer devices still
show no corrosion. At this magnification, 1 mm would measure 3 m!
Nickel corrosion
in a biologic environment
A corrosion of 10% would produce a
huge crater at 3000 times
magnification and the daily dose of
nickel would have been 15.4
micrograms, 33 times less than the
daily intake.
Conclusion
Edie JW, et al. Angle Orthod 1981;51,4:319-24
“In conclusion, the results reported here
suggest that there is no reason to believe
that Nitinol wires are any more subject to
corrosion than stainless steel wires in an
environment that is typical of clinical
service.”
Edie JW, et al (1981)