Determining cardiac arrhythmia from a video of a subject being monitored for cardiac function

17 Pages·2014·1.45 MB·English

US 20140221845A1
(19) United States
(12) Patent Application Publication (10) Pub. No.: US 2014/0221845 A1
MESTHA et al. (43) Pub. Date: Aug. 7, 2014
(54) DETERMINING CARDIAC ARRHYTHMIA (52) US. Cl.
FROMA VIDEO OF A SUBJECT BEING CPC ....... .. A6IB 5/02433 (2013.01); A6IB 5/02405
MONITORED FOR CARDIAC FUNCTION (2013.01); A6IB 5/725 (2013.01); A6IB
5/7257 (2013.01); A6IB 5/7282 (2013.01);
(71) Applicant: Xerox Corporation, Norwalk, CT (US) A613 5/742 (2013,01)
USPC ......................................... .. 600/473; 600/479
(72) Inventors: Lalit Keshav MESTHA, Fairport, NY
(US); Beilei XU, Pen?eld, NY (US); (57) ABSTRACT
Paul R. AUSTIN, Webster, NY (US)
What is disclosed is a system and method for processing a
(73) Assignee; XEROX CORPORATION, Norwalk, time-series signal generated by video images captured of a
CT (US) subject of interest in a non-contact, remote sensing environ
ment such that the existence of a cardiac arrhythmia can be
(21) Appl. No.: 14/245,405 determined for that subject. In one embodiment, a time-series
signal generated is received. The time-series signal was gen
(22) Filedi APF- 4, 2014 erated from video images captured of a region of exposed skin
Where photoplethysmographic (PPG) signals of a subject of
Related US“ Application Data interest can be registered. Signal separation is performed on
(63) Continuation_in_pan of application NO_ 13/532,128, the time-series signal to extract a photoplethysmographic
?led on jun~ 25’ 2012~ signal for the subject. Peak-to-peak pulse points are detected
in the PPG signal using an adaptive threshold technique With
Publication Classi?cation successive thresholds being based on variations detected in
previous magnitudes of the pulse peaks. The pulse points are
(51) Int. Cl. then analyzed to obtain peak-to-peak pulse dynamics. The
A61B 5/024 (2006.01) existence of cardiac arrhythmias is determined for the subject
A61B 5/00 (2006.01) based on the pulse dynamics.
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