Information Notice No. 86-59: Increased Monitoring of Certain Patients with Implanted Coratomic, Inc, Model C-100 and C-101 Nuclear-Powered Cardiac Pacemakers

                                                           SSINS. No.: 6835 
                                                           IN 86-59        

                                UNITED STATES
                           WASHINGTON, D.C. 20555

                                July 14, 1986

                                   WITH IMPLANTED CORATOMIC, INC, MODEL 
                                   C-100 AND C-101 NUCLEAR-POWERED CARDIAC 


All NRC licensees authorized to use nuclear-powered cardiac pacemakers. 


This notice is to alert users of Coratomic, Inc. Model C-100 and C-101 
nuclear-powered cardiac pacemakers of the manufacturer's recent warning of 
possible problems with certain units. The manufacturer recommends increased 
monitoring of patients with these units implanted. It is expected that 
licensees will review this information for applicability to their patients 
and consider actions, if appropriate. However, suggestions contained in this
information notice do not constitute NRC requirements, therefore, no 
specific action or written response is required. 

Description of Circumstances: 

By letter dated March 14, 1986, the manufacturer, Coratomic, Inc., notified 
applicable attending physicians of possible problems with Model C-100 and 
C-101 plutonium-powered pacemakers that were manufactured between September 
1974 and October 1977. During that time, "2CN potting material," a glue-like
substance, was used in the construction of the pacers. The reversion of the 
2CN potting material to a viscous form in some units has lead to a rate drop
and to a higher-than-anticipated random transformer failure rate. 
Accordingly, Coratomic recommends that the monitoring of affected patients 
be increased to once every 3 months. The March 14 letter included a listing 
of affected patients. 


There is no radiological hazard associated with the problem described in 
Coratomic's March 14, 1986 letter. However, this notice serves as a reminder
that, as a condition of their license, licensees are required to follow the 
manufacturer's protocol and to notify the NRC within 10 days of loss of 
contact with a nuclear pacemaker patient. If you have any difficulty 
locating or contacting any affected patient, the NRC suggests you contact 
the manufacturer for assistance. However, since the Coratomic protocol, 
dated either August 1, 1974 or November 1, 1975, specifies in-person 
followup visits every 6 months for patients with Coratomic Model C-100 or 
C-101 pacemakers implanted for more than 6 months, you should have no 
difficulty in contacting affected patients. 

                                                              IN 86-59     
                                                              July 14, 1986 
                                                              Page 2 of 2  

No specific action or written response is required by this information 
notice. If you have any questions regarding this matter, please contact the 
Regional Administrator of the appropriate NRC regional office or this 

                                   James G. Partlow, Director 
                                   Division of Inspection Programs 
                                   Office of Inspection and Enforcement 

Technical Contact:  J. R. Metzger, IE

Attachment: List of Recently Issued IE Information Notices 

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