Postmortem ICD interrogation in mode of death classification

Area of Science:

• Cardiology
• Forensic Medicine
• Medical Device Technology

Background:

• Sudden death definition often relies on symptom-to-death timing, which may not accurately reflect the cause.
• Not all sudden deaths are attributable to cardiac arrhythmias.
• Implantable cardioverter defibrillators (ICDs) offer a potential tool for postmortem analysis to determine the mode of death.

Purpose of the Study:

• To determine the proportion of sudden cardiac deaths in patients with ICDs that are confirmed to be caused by arrhythmia.
• To evaluate the utility of postmortem ICD interrogation in classifying the mode of sudden cardiac death.

Main Methods:

• A systematic literature search was performed for studies involving postmortem ICD interrogation and time-based death classification.
• Risk of bias was assessed using a modified QUADAS-2 checklist.
• Outcome data were pooled from relevant studies.

Main Results:

• The analysis included 22 studies (1982-2015) with 23,600 participants.
• Pooled results indicate that 76% of sudden deaths (CI 67-85%) showed evidence of ventricular arrhythmias.
• Excluding high-risk studies, 24% of sudden deaths were identified as nonarrhythmic via postmortem ICD interrogation.

Conclusions:

• Postmortem ICD interrogation is a valuable tool for distinguishing arrhythmic from nonarrhythmic sudden cardiac deaths.
• Approximately one-quarter of sudden deaths in ICD patients may not be primarily caused by arrhythmia.
• Device interrogation should be considered in the investigation of all unexplained sudden cardiac deaths.