Pacemaker pin points time of death in murder caseBMJ 2003; 326 doi: https://doi.org/10.1136/bmj.326.7380.70/a (Published 11 January 2003) Cite this as: BMJ 2003;326:70
A murdered man's pacemaker has been used to give a coroner vital evidence about the victim's ordeal.
Almost two days after the man was beaten to death, doctors were able to view the pacemaker's records and produce data for the duration of the incident. By analysing the data they were able to pinpoint crucial times, including when he was awoken, time spent walking around, the altercation with the intruder, and the time of the beating and his death.
The case, reported in the Journal of Pacing and Clinical Electrophysiology (2002;25:1406-8), involved a 72 year old man who had a dual chamber pacemaker implanted for complete heart block and who was found early one morning in his nightclothes outside his home, beaten to death. He had severe blunt force injuries to the head and massive blood loss.
Finding the pacemakers' pacing leads and pulse generator to be undamaged at the postmortem examination, the coroner asked for telemetric information on the victim's response to the assault and the time of death. Doctors at the Royal Melbourne Hospital retrieved around 37 hours of data some 33 hours after the body was found.
“Paced and sensed event information along with timing pulses used to decode the real-time of the recorded activity are stored digitally within the pulse generator. It can be retrieved telemetrically using the pacemaker programmer, and may provide documentation of the entire pacemaker sensed and paced profile for a given period,” says the report.
A period of 1 hour, 13 minutes, and 17 seconds was examined in detail, showing a telemetric footprint of the patient's pacing and sensed events leading to death. Until 4 40 that morning, the rhythm was consistent with the victim's being asleep. At 4 43 am there was an abrupt increase in sinus activity up to the programmed maximum tracking rate and other changes, which probably represented the man's initial awakening, his walking around and altercation with the intruder, and finally the beating. This continued until 5 10 am, when there was around 17 minutes of chaotic activity, with death at about 5 30 am.
“These telemetric footprints provided valuable time stamps on the events that led to the victim's death,” says the report. “This case study highlights the value of a sophisticated telemetered pacemaker event record extending over almost 40 hours together with a wide range of time and zoom scales down to 15 seconds.”