Location-specific diagnostic information is detected and recorded by the cardiac stimulation device for subsequent display using the external programmer device. The diagnostic information includes location-specific event records, counters and IEGM signals. The event records include event codes that distinguish among events occurring in the four chambers of the heart, such as sensed or paced events occurring within the left or right atria or the left or right ventricles. The counters separately count events occurring within the chambers of the heart. The IEGM signals are separately detected within the four chambers of the heart using a multiple sensing lead arrangement. The location-specific event records, counters and IEGM signals are ultimately transmitted to the external programmer, which displays graphic representations of the diagnostic information. The event records are displayed using distinct event marker icons which distinguish among the four chambers of the heart. The distinct event marker icons are displayed along with location-specific IEGM displays or surface ECG displays to permit a physician operating the programmer to easily identify the specific chambers of the heart in which events the occurred. Additionally, the programmer displays the values of the various counters to provide, for example, a set of location-specific histograms. The diagnostic information detected and recorded by the stimulation device and displayed by the external programmer device may further distinguish among events detected at multiple locations within each chamber of the heart. Method and apparatus embodiments are described.