DISCRIMINATING BETWEEN ATRIAL FIBRILLATION AND SINUS RHYTHM IN PHYSIOLOGICAL SIGNALS OBTAINED FROM VIDEO

摘要

What is disclosed is a system and method for determining whether a subject is in atrial fibrillation. A video is received of a region of exposed skin of a subject. The video is acquired of a region where a videoplethysmographic (VPG) signal can be registered by at least one imaging channel of a video imaging device. For each batch of image frames, pixels associated with the region of exposed skin are isolated and processed to obtain a time-series signal. A VPG signal is extracted from the time-series signal. The power spectral density (PSD) is computed across all frequencies within the VPG signal. A pulse harmonic strength (PHS) is calculated for this VPG signal. The pulse harmonic strength is compared to a discrimination threshold, defined herein. A determination is made whether the subject in the video is in atrial fibrillation or in normal sinus rhythm.

主权项

1. A method for determining whether a subject is having an atrial fibrillation event, the method comprising:
receiving a video of a region of exposed skin of a subject where a videoplethysmographic (VPG) signal can be registered by at least one imaging channel of a video imaging device used to capture that video; defining a size N of a batch of image frames such that Nmin≦N≦Nmax, where Nmin is a minimum size of a batch of image frames and Nmax is a maximum size of a batch of image frames; and for each batch of image frames of size N:
processing this batch of image frames to isolate pixels associated with said region of exposed skin;processing said isolated pixels to obtain a time-series signal for this batch;extracting a VPG signal from said time-series signal;computing a power spectral density across all frequencies within said VPG signal;calculating a pulse harmonic strength for this VPG signal;comparing the pulse harmonic strength to a discrimination threshold; anddetermining, as a result of said comparison, that said subject is one of: in atrial fibrillation, and in sinus rhythm.