Dynamic Large Artery Stiffness Index for Cuffless Blood Pressure Estimation
Shresth Gupta, Anurag Singh, Abhishek Sharma
Abstract
Proper blood pressure measurement is essential for diagnosis and appropriate medical treatment for cardiovascular disease and hypertension. Numerous attempts were made to derive meaningful features from photoplethysmogram (PPG) to correlate with mean arterial pressure (MAP) and pulse pressure (PP), however, satisfactory performance could not be achieved yet. This letter proposed an enhanced index termed dynamic large artery stiffness index to analyze the contour of PPG between systolic and diastolic points and employed its contribution toward noninvasive cuffless blood pressure estimation and as a significant biomarker for cardiovascular status. The proposed index demonstrated a good association with MAP and PP with average Pearson correlation coefficients of 0.87 and 0.65, respectively. The proposed index is combined with 12 other prominent PPG features to estimate systolic, diastolic, and mean arterial pressure. The estimation results yield mean absolute errors (with standard deviation) of (0.55 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 1.62), (0.32 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 0.89), and (0.35 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 0.95) for SBP, DBP, and MAP, respectively, on MIMIC-I database while (2.41 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 5.26), (0.41 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 1.50), and (0.65 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 1.34) on UCI repository database. It achieves grade-A by comparison with the global standard benchmark of British Hypertension Society for all the three estimations, i.e., SBP, DBP, and MAP.