Abstract 15697: Fingertip-Based Monitoring of Vascular Reactivity and Endothelial Function: A Three-Way Comparison of Testing Modalities
Introduction: In recent years fingertip-based measurement of vascular reactivity and endothelial function using a 5-min arm-cuff reactive hyperemia protocol has become a clinical tool for clinicians to evaluate patients in the exam room. Our group previously introduced Digital Thermal Monitoring (DTM) as a simple, easy and operator-independent test that measures vascular reactivity and endothelial function by monitoring fingertip temperature. Recently we developed fingertip photoplethysmography (PPG). In this study, we performed a simultaneous comparison of the three methods to evaluate their similarities and dissimilarities.
Hypothesis: We hypothesized that PPG correlates strongly with PAT and could be used as a replace.
Methods: Cuff-induced reactive hyperemia protocol (5 min. baseline, 5 min. ischemia, 5 min. post deflation) tests were performed with simultaneous recording of signals from PAT Pressure sensors (on index finger), DTM temperature sensors (3rd finger), and PPG photoelectric sensors (4th finger). A total of 39 tests were performed on 17 individual subjects. Signal data were analyzed, cross correlated, and graphed using Excel software and MATLAB functions.
Results: As shown in Figure below, all three modalities showed similar patterns. Analyses of data during reactive hyperemia phase showed the strongest correlation between PPG and PAT (mean crosscorr = 0.79), compared to PAT and DTM (mean crosscorr = 0.64) and PPG and DTM (mean crosscorr = 0.49).
Conclusions: DTM, PPG, and PAT signals are well correlated. The strong correlation between PPG and PAT suggests they can be used interchangeably.
Author Disclosures: M. Naghavi: None. A. Lin: None. S. Kleis: None. A. Yen: None.
- © 2015 by American Heart Association, Inc.