Search for: fmd
Autoregressive modeling of the photoplethysmogram AC signal amplitude changes after flow-mediated dilation in healthy and diabetic subjects, Article 2012 19th Iranian Conference of Biomedical Engineering, ICBME 2012 ; 2012 , Pages 170-173 ; 9781467331302 (ISBN) ; Zahedi, E ; Behnia, F ; Sharif University of Technology
It is proved that the endothelial (artery inner lumen cells) function is associated with cardiovascular risk factors. Among all the common non-invasive methods employed in the research setting for assessing endothelial function, flow-mediated dilation is the most widely used one. This technique measures endothelial function by inducing reactive hyperemia using temporary arterial occlusion and measuring the resultant relative increase in blood vessel diameter via ultrasound. In this paper, the limitations associated with the ultrasound technique are overcome by using the photoplethysmogram (PPG) signal recorded during FMD. The correctness of this approach is investigated by modeling the AC...
Evaluation of endothelial response to reactive hyperaemia in peripheral arteries using a physiological model, Article International Journal of Biomedical Engineering and Technology ; Volume 33, Issue 4 , 2020 , Pages 305-324 ; Zahedi, E ; Vahdat, B. V ; Sharif University of Technology
Inderscience Publishers 2020
Non-invasive measurement of flow-mediated dilation (FMD) in the brachial artery for assessing endothelial function is costly and operator-dependent, limiting its application to research cases. In this paper, an approach based on a physiological model between normalized central blood pressure and finger photoplethysmogram is presented. Baseline model parameters are estimated using a genetic algorithm in 30 subjects consisting of ten normal blood pressure (BP), ten high-BP and ten elderly volunteers. Beat-to-beat fitness values after reactive hyperaemia are calculated using baseline (before cuff occlusion) data. Results show that stimulus-induced changes are fairly described with a first order...