Data storage and retrieval by implantable pacemakers for diagnostic purposes

The functions of many of today's dual-chamber pacemakers are performed using custom microprocessors that are similar to those used in mainframe computers. The data storage and transmission capabilities of these microprocessor-controlled pacemakers can be used to record, process, and transmit information regarding the patient, pacemaker, or patient/pacemaker interaction. The limitations of such data processing systems depend upon (1) quantity and quality of incoming information, (2) software routines for data collection, and (3) the amount of available random access memory (RAM). Data obtained can be useful in patient management and follow-up, particularly in the areas of optimization of programming, monitoring of disease progression, assessment of pharmacologic therapy, and pacemaker troubleshooting. Anticipated advances in data collection capabilities will allow increasingly sophisticated analysis that will complement, and may in some cases, supplant the Holter monitor recording in evaluating some aspects of rhythm and/or pacemaker behavior in selected patients.