Modeling of artifacts in the wrist photoplethysmogram: Application to the detection of life-threatening arrhythmias

摘要

Objective: A model for simulating motion-induced artifacts in the wrist photoplethysmogram (PPG) is proposed for the purpose to improve realism of PPG models.Methods: The database of day-long PPGs, acquired during cardiac rehabilitation, is used to extract artifact characteristics, which further serve as a basis for modeling artifacts in simulated PPGs with life-threatening arrhythmias.Results: Depending on the recording, 14-49% of the PPG duration is corrupted by artifacts, mostly due to device displacement, forearm and hand motion. The artifact type influence on the performance of a life-threatening arrhythmia detector shows that the sensitivity drops by 45-48% for extreme bradycardia and by 13-32% for ventricular tachycardia. Poor contact causes 2-4 times more false alarms of ventricular tachycardia compared to the other artifact types under investigation.Conclusion: Simulation of realistic artifacts encountered in activities of daily living allows to comprehensively investigate arrhythmia detectors and understand the artifact types most negatively affecting detection performance. Significance: The proposed PPG artifact model is of importance for developing and testing artifact-robust arrhythmia detectors.