Abstract

A pacemaker or other implantable medical device stores diagnostic information pertaining to a variety of events detected pacemaker for subsequent transmission to an external programmer. The external programmer displays graphical representations of the diagnostic information under the control of a physician operating the programmer. In one example, the pacemaker senses events occurring within the heart during a refractory period following generation of a stimulation signal, stores diagnostic information pertaining to those events as "event records" within the pacemaker, and ultimately transmits the event records to the external programmer for display in various graphical formats. The events occurring during the refractory period include events such as a P-wave detected during a relative post-ventricular atrial refractory period not followed by a ventricular pulse or an R-wave detected during a relative ventricular refractory period or a P-wave detected during an atrial refractory period during an AV/PV interval. Other examples of diagnostic information stored by the pacemaker include information pertaining to operations triggered within the pacemaker as a result of the condition of the patient, such as an auto-mode switching event, or as a result of the condition of the pacemaker itself, such as a battery test operation. Still other examples of diagnostic information recorded by the pacemaker and displayed by the external programmer include information pertaining to programming signals received from the external programmer, such as a heart base rate and rest rate re-programming signals.