Photoplethysmogram Modeling of Extreme Bradycardia and Ventricular Tachycardia

Abstract

A model for simulating life-threatening arrhythmias, namely, extreme bradycardia and ventricular tachycardia, in photoplethysmogram (PPG) signals is proposed. The model uses RR interval series as an input, thus publicly available ECG databases can be employed to generate PPG signal database. The model has been originally developed for simulating atrial fibrillation, however, is adjusted to better represent the variation in PPG pulse amplitude, intrinsic to life-threatening arrhythmias. The original and adjusted models are evaluated on 40 recordings containing the episodes of extreme-bradycardia and ventricular tachycardia. By using the adjusted model, the root mean square error between real and modeled PPG signals is reduced, on average, by 20.6% for extreme bradycardia, whereas remains similar for ventricular tachycardia. The simulator is expected to be valuable when developing PPG-based wearable devices for long-term monitoring of patients at high risk of sudden cardiac death due to life-threatening arrhythmias.