This advisory is limited to devices identified in the
product model list that were implanted subpectorally. Devices implanted
subcutaneously are not included in this advisory.
Boston Scientific has determined that the bond between the
header and case could be weakened by significant forces associated with a
subpectoral implant procedure or when a device in a subpectoral position is
pushed against a rib during contraction of the pectoralis muscle. A weakened
header bond may alter lead impedance and introduce noise that may inhibit
pacing therapy or initiate inappropriate tachy therapy. Additional mechanical
stress applied to a weakened bond may eventually cause header connection wires
to fracture, resulting in loss of therapy.
A weakened header bond can result in one or more of the
following device behaviors: - Significant changes in measured lead impedance -
Noise on real-time or stored electrograms - Intermittent inhibition of pacing -
Inappropriate anti-tachy pacing or shock therapy - Loss of pacing therapy -
Loss of anti-tachy pacing and shock therapy
No patient deaths related to this behavior have been
reported. Patients have required early device replacement due to inappropriate
shocks and/or noise induced by pocket manipulation or arm movement.
Reported Events and Rate of Occurrence
The implant orientation of devices is not reported to Boston
Scientific, making it difficult to provide rate of occurrence and prediction
information. Two (2) reports have been received worldwide of subpectoral
implants with weakened header bonds. An estimated 5% of approximately 77,000
COGNIS and TELIGEN devices worldwide have been implanted in a subpectoral
location.
The following factors may also impact the risk of failure if
implanted in a subpectoral location: - Exact location of the patient's ribs
relative to the device - Body size and/or muscle mass of the patient (risk may
increase for larger/muscular patients) - Activity level and/or occupation of
the patient (risk may increase for more active patients)
Reported Events (worldwide)
Two (2) reports have been received worldwide of subpectoral
implants with weakened header bonds. An estimated 5% of approximately 77,000
COGNIS and TELIGEN devices worldwide have been implanted in a subpectoral
location. There have been no reported patient deaths associated with this
advisory.
Rate of Occurrence
The implant orientation of devices is not reported to Boston
Scientific. For this reason, no rate of occurrence or rate projection is
provided.
Recommendations
- If a patient's device was implanted subcutaneously, it is
excluded from this advisory and no change to current patient management is
recommended. - For future implants: - Boston Scientific recommends that
subpectoral implantation of affected COGNIS CRT-Ds or TELIGEN ICDs be avoided
until improvements to header bond strength are available for devices in your
geography. - For affected devices implanted in a subpectoral location: -
Follow patient at least once every three months as recommended in device
instructions for use. - Consider advising patients to contact their physician
or clinic if they receive shocks, in order to ensure timely review of
associated electrograms and other device data via in-clinic or remote
interrogation. - Where available, consider using the LATITUDE® Patient
Management System to facilitate remote device checks between in-clinic
follow-ups. (Note to reviewers: the trademark symbol will be superscripted in
finished text.) - The Standard Warranty program is available; please contact your
local representative for terms and conditions.
With respect to the number of reported events listed in the
summaries above, Boston Scientific recognizes that the actual number of
clinical malfunctions may be greater than the number actually reported.
Additionally, rate projections are provided with the acknowledgement that
predictive modeling is inherently uncertain due to its dependence on the device
age distribution of reported events and resultant statistical approximation and
assumptions.
Advisory notifications may vary by geography, based upon
local regulatory requirements. Please contact the local Boston Scientific
office for more information. Not all products may be approved for use in all
geographies, as product approval is geography specific.
SOURCE: Boston Scientific