Dear Doctor Letter (June 23, 2005)

Re CONTAK RENEWAL 3 and 4, RENEWAL 3 and 4 AVT, and RENEWAL RF):

This letter is intended to advise physicians and their patients about the problem
and to limit adverse events. FDA may consider this action as a recall. At this
time, we are in the very early stages of a diligent evaluation of the component
failure described below. We will continue our evaluation and communicate with
you further as more information is learned. As a precautionary measure,
physicians should discontinue implants of these devices pending further notice.

Guidant's Cardiac Rhythm Management Quality System has determined that the
device listed above are subject to a component failure that may limit available
therapy. Engineering analysis has determined that the magnetic switch in these
devices may stick in the closed position. Four occurrences have been confirmed
out of approximately 46,000 devices; a fifth occurrence is suspected but cannot
be confirmed. In the four occurrences in which the device was implanted,
patients and/or physicians were alerted to the condition by audible device tones
that signaled the magnetic switch was closed. These four occurrences have
resulted in device replacement. One occurrence occurred prior to implant.

Clinical Implications
: In normal device function, application of a magnet closes the magnetic switch
and enables the magnet mode that controls temporary device function. If Enable
Magnet Use is programmed ON, as it is in default settings, and the magnetic
switch becomes stuck in the closed position, treatment if ventricular or atrial
tachyarrhythmais is inhibited, while bradycardia pacing is unaffected. Under
these conditions, device safety features will cause the device to emit tones, and
battery depletion will be accelerated. If Enable Magnet Use is programmed
OFF and the magnetic switch becomes stuck in the closed position, the device
will continue to provide tachyarrhythmia therapy and bradycardia pacing
therapy as programmed; however, the remaining device life will be reduced
significantly. Elective replacement indicators (ERI), including audible tones (if
activated as in default settings), remain intact though the time between ERI and
end-of-life (EOL) indicators may be shortened.

Recommendations
Programming Enable Magnet Use 'OFF' will ensure that appropriate therapy
to treat ventricular and atrial tachyarrhythmias will be provided in the event that
the magnetic switch becomes stuck in the closed position.
Devices Impacted/Device Family Model Number
Contak Renewal 3 / H170, H173, H175
Contak Renewal 3 HE / H177, H179
Contak Renewal 4 / H190, H195
Contak Renewal 4 HE / H197, H199
Contak Renewal 3 AVT / M150, M155
Contak Renewal 3 AVT HE / M157, M159
Contak Renewal 4 AVT / M170, M175
Contak Renewal 4 AVT HE / M177, M179
Renewal RF / H230, H235
Renewal RF HE / H239