ACCOLADE SR Pacemaker

On December 19, 2017 the firm sent a letter to all their medical consignees stating the following: December 2017 Dear Doctor, Boston Scientific has received reports of intermittent oversensing of the Minute Ventilation (MV) sensor signal with certain Boston Scientific pacemaker and cardiac resynchronization therapy pacemaker systems (pacemakers). MV sensor signal oversensing may cause pre-syncope or syncope due to periods of pacing inhibition. This MV behavior may occur with any manufacturers pacing lead system, but Boston Scientific has determined it to be more likely for affected Boston Scientific pacemakers using Medtronic or Abbott/St. Jude (Abbott) leads implanted in either the right atrium (RA) or right ventricle (RV). Boston Scientific is actively developing a software update designed to automatically detect and resolve this MV sensor signal oversensing behavior. We anticipate submitting the software update to Regulatory Agencies in March 2018 and pending approval, will release it as soon as possible thereafter. Until this software update is available, Boston Scientific has additional re commendations to mitigate this risk for affected pacemaker systems. Root Cause Investigation The MV sensor in Boston Scientific pacemakers can be used for RightRate" (rate adaptive pacing), Respiratory Rate Trend, or AP Scan"1. When the RA/RV pacing leads and lead terminal connections are operating as intended, the MV sensor signal is appropriately filtered and therefore is not detected by the pacemaker or displayed on electrograms (EGMs). However, intermittency related to the lead or pacemaker-lead connection2 has the potential to create a transient high impedance condition. A high impedance condition may subsequently alter the MV sensor signal such that it becomes visible on EGMs and potentially subject to oversensing on the RA or RV channels. For a technical description of the Boston Scientifics MV sensor, please refer to Appendix A. Engineering analysis and