The ability to identify premature arterial stiffening is of considerable value in the prevention cardiovascular diseases. “ageing index” ( AGI ), which calculated from second derivative photoplethysmographic (SDPPG) waveform, has been used as one method for stiffness estimation and evaluation ageing. In this study, new SDPPG analysis algorithm proposed with optimal filtering signal normalization time. filter parameters were optimized order achieve minimal standard deviation , gives more...

The aim of this research was to assess the validity photoplethysmographic (PPG) waveform index PPGAI for estimation increased arterial stiffness. For purpose, PPG signals were recorded from 24 healthy subjects and 20 type II diabetes patients. processed with analysis algorithm developed similar augmentation (AIx) calculated. As a reference, aortic AIx assessed normalized heart rate 75 bpm (AIx@75) by SphygmoCor device. A strong correlation (r = 0.85) between AIx@75 positive both indices age...

The <i>Journal of Biomedical Optics</i> (JBO) is a Gold Open Access journal that publishes peer-reviewed papers on the use novel optical systems and techniques for improved health care biomedical research.

Proposed paper is a part of research to develop convenient method for continuous monitoring blood pressure by non-invasive and non-oscillometric way. The based on presumption that there singular relationship between the velocity pulse wave person. detection registration mechanical movements vessel's walls computing time delay in different regions human body using an ECG as reference signal. Additional information about evaluation gotten from photoplethysmographic (PPG) channel. Used optical...

This study analyses the photoplethysmographic (PPG) signal waveform rising front in order to discriminate subjects with premature increase arterial ageing.As a reference measure for evaluation of system, aortic augmentation index (AIx@75) was calculated using SphygmoCor device.The carried out on 24 healthy and 20 diabetes patients.Negative correlation relationships (r = -0.68 r -0.77)were found between age slopes PPG signal.Significant differences were controls patients.The highest...

The aim of this study was to assess pulse wave velocity (PWV) and augmentation index in different arteries patients with severe coronary heart disease (CHD). Signal measurements were obtained from 28 subjects. Severe confirmed by angiography. Aortic PWV Augmentation Index measured using the TENSIOMed Arteriograph. Four other velocities (upper limb PWV1, upper PWV2, PWV3 lower PWV) PowerLab 4/20T device. It found that aortic significantly increased CHD group compared control (P<0.01). This...

Current work is a part of long term research, which aim to study the possibilities diagnose atherosclerosis in early stadium by using pulse wave velocity and its waveform analysis. The mobile experimental measurement complex built technically tested for hospital. Measurement consists ten physiological signal recording channels reference devices: Sphygmocor, Arteriograph, Finapres. measurements with this are planned carry out during six month on patients different severity coronary disease diabetes.

Associations found between pulse wave velocity (PWV) and cardiovascular risk factors (CVrF) are diverse. We aimed to evaluate whether differences in PWV its associations with CVrF a high population exist genders the whole (WHgr) groups of apparently healthy (AHgr) those hypertensive, obese or diabetics (Rgr).Pulse measured by Arteriograph was investigated 805 adults aged 20-65, randomly selected from Tallinn Population Register.Pulse highest Rgr no were same group. In women WHgr AHgr age SBP...

Pulse transit time, which correlates with blood pressure, is measured between the electrocardiogram R-wave peak and 50% raising front level of a photoplethysmographic (PPG) signal.Registered PPG signal bandwidth may be shared by noise therefore undetectable.Electrocardiogram reference adaptive sum comb filter was used to extract harmonic components suppress noises them.Averaging effect on studied adjustments were made.The influence filtered measurement pulse time analysed.

The aim of this study was to determine the association left ventricular (LV) geometry with sex, age, arterial hypertension and obesity in Tallinn. In a framework population for cardiovascular risk factors, echocardiography carried out 325 men 398 women (69.3% all 1043 participants aged 35–59) 1999–2001. Left hypertrophy defined if mass (LVM), LVM/height LVM/body surface area were 294 g, 163 g/m 150 2 men, 198 121 120 women, respectively. LV analysed according four types generally recognized...

For applications where PPG signal AC component needs to be measured without disturbances in its shape and recorded digitally with high digitalization accuracy, the step- by-step DC eliminator is developed. This paper describes step-by-step eliminator, which utilized analogue comparator operational amplifier. It allows record 24-hours monitoring system. The experiments have been carried out.

This paper gives an overview of a research, which is focused on the development convenient method for continuous non-invasive monitoring arterial blood pressure (BP).The based presumption that there single relationship between pulse wave propagation time in system and BP.The transit (PWTT) measurement involves registration two markers, one usually ECG another detection peripheral arteries.This study makes comparative evaluation four different methods detection: 1) self-mixing diode laser,...

The study was carried out in order to analyse the changes photoplethysmographic (PPG) signal waveform, which are caused by cold and warm stimulation. on 7 subjects. right hand immersed water up wrist during experiment. PPG registered from index finger. As a reference, temperatures of finger pulse transit time (PTT) values were measured. A correlation r=-0.70 found between normalised slope subject's age. increased noticeably due decreased It opposite expected results with PTTs behaviour has...

Measured PPG signals can be often affected by noises and motion artefacts. The usual band-pass filter does not remove noises, which are sharing the same frequency band as signal. signal AC component fundamental harmonic all other multiples of extracted comb filter. adaptive has been proposed, uses ECG reference. Comparative experiments have carried out.

The aim of the study was to determine whether different sleep stages, especially REM sleep, affect QT interval duration and variability in male patients without obstructive apnea (OSA). Polysomnographic recordings 30 were analyzed. Beat-to-beat calculated using QTV index (QTVI) formula. For QTc calculation, addition Bazett’s formula, linear parabolic heart rate correction formulas with two separate α values used. QTVI as means 2 awake, 3 NREM, episodes; each episode 300 sec. Mean not...

AC component of photoplethysmography signal carries important information for diagnostics. Registered may be affected by noises, which are sharing the same bandwidth. Adaptive comb filter is used extraction. Due to averaging behavior it decreases shape difference between consecutive beats. Comb needs adjusted PPG signal. new weight values determined through numerical computation. Experiments with generated photoplethysmographic signals were carried out compare and non-adjusted adaptive sum filter.