Comparison of median filter and discrete dyadic wavelet transform for noise cancellation in electrocardiogram.

Development of noise cancellation algorithm is essential to facilitate accurate detection of electrocardiogram (ECG) in mobile health and wearable medical devices. In this study, we captured ECG from 20 subjects when they were at rest and during routine activities. The motion artifact in ECG was filtered using two non-linear filters: median filter and discrete dyadic wavelet transform.

The effects of pre-ejection period on post-exercise systolic blood pressure estimation using the pulse arrival time technique.

Pulse arrival time (PAT) is comprised of the vascular transit time (TT) through the arterial system and the pre-ejection period (PEP) in the heart. It has been used to predict arterial blood pressure (BP) without using a cuff. The aim of this study was to investigate the effects of including the PEP on the accuracy of cuffless systolic BP (SBP) estimation using the PAT technique in post-exercise recovery.

The acute effects of running on blood pressure estimation using pulse transit time in normotensive subjects.

Pulse transit time (PTT) is a potential parameter for cuffless blood pressure (BP) estimation. Since exercise induces changes in arterial properties that can influence the relationship between BP and PTT, we investigate whether PTT can be used to estimate BP after successive bouts of exercise. PTT-foot, PTT-peak (time intervals from the peak of electrocardiogram R-wave to the foot and peak of photoplethysmogram, respectively) and BP of 41 normotensive subjects (aged 25 +/- 4 years) were measured in the first test.

An evaluation of the cuffless blood pressure estimation based on pulse transit time technique: a half year study on normotensive subjects.

In the present study, we investigated the relationship between blood pressure (BP) and pulse transit time (PTT) and evaluated the accuracy of the PTT-based cuffless BP estimation on 14 normotensive subjects. Least-squares regression was used to estimate BP in the first test and a repeatability test carried out half year later. BP in the repeatability test was also estimated using the regression coefficients in the first test.