PPG Accuracy

The accuracy of Corsano CardioWatch 287 with pulse detection using photoplethysmography technology in cardiac patients was studied by S. Blok [1,2], M.A. Piek [1], I.I. Tulevski [1], G.A. Somsen [1], M.M. Winter [1,3].

In this single-centre prospective study, patients from an outpatient cardiology clinic underwent a simultaneous resting ECG and PPG recording. 180 patients a total of 7,914 ECG beats were recorded and 7,880 (99%) were also recorded by PPG. Figure 1 displays an example of a 45 second PPG and ECG measurement. The PPG-accuracy, defined as the proportion of PPG measurements within 100 ms of ECG measurements, was 94.6% (95%CI 94.1-95.1). Correlation was high for HR (R = 0.991 (95%CI 0.988-0.993), n = 180) (Figure 2A). The 95% Limits of Agreement (LoA) were -3.89 to 3.77 (mean bias -0.06) beats per minute (Figure 2). The RR-intervals on the PPG were highly correlated with those on the ECG (R = 0.966 (95%CI 0.964-0.968), n = 6,139) (Figure 3A), with a narrow 95% LoA of -85 to 85 (mean bias -1) ms (Figure 3B). This study showed that the Corsano 287 Bracelet with PPG-technology can determine HR and RR-intervals with high accuracy in cardiovascular at-risk patient population among different subgroups.

ECG vs PPG

Figure 1- Simultaneous recordings of PPG and ECG data. PPG measurement was started before and ended after the ECG registration. Non-matching PPG heartbeats were automatically matched to the closest P-top on the ECG-signal 

Correlation BPM

Figure 2 - A. Correlation of HR-determination (beats per minute) between PPG and ECG. B.  Limits of Agreement (LoA) of HR-determination between PPG and ECG, the 95% LoA are marked by the dotted lines.

Correlation RR Intervals

Figure 3 - A. Correlation of determination of RR-intervals between PPG and ECG; the +/- 100ms range is marked by the dotted lines. B. Limits of Agreement (LoA) of determination of RR-intervals between PPG and ECG, the 95% LoA are marked by the dotted lines.

References

  1. Department of Cardiology, Cardiology Centers of the Netherlands. Karel du Jardinstraat 61, Amsterdam, the Netherlands

  2. Department of Vascular Medicine, Internal medicine, Amsterdam UMC, University of Amsterdam, Amsterdam Cardiovascular Sciences, Meibergdreef 9, Amsterdam, The Netherlands

  3. Department of Cardiology, Amsterdam UMC, University of Amsterdam, Amsterdam Cardiovascular Sciences, Meibergdreef 9, Amsterdam, The Netherlands