Browsing by Author "Omari, Tahar"

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Cardio-ankle vascular index (CAVI) is a potential new parameter independent of blood pressure at the time of measurement for arterial stiffness estimation
(2023) Radjef, Lilia; Omari, Tahar; Baiche, Karim
The cardio-ankle vascular index (CAVI) is a robust predictor of cardiovascular events. An innovative, non-invasive approach to measuring arterial stiffness. The (CAVI) approach was developed to overcome the limitations of carotid -femoral pulse wave velocity (cf-PWV), the gold standard indicator of arterial stiffness. The present study aims to propose a new algorithm to calculate the cardio-ankle vascular index (CAVI) parameter from Pulse Wave Database (PWDB), that contains the pulse waves of 500 virtual subjects aged between 25 and 75 years, generated from cardiovascular characteristics. The results obtaine d are promising in terms of sensitivity (SEN) and accuracy (ACC). The sensitivity values are (95.18 %, 95.71%, 92.70 %, 90.33%, 89.28%, and 89.05%), and accuracy (ACC) are (91%, 89.4%, 86.4 %, 80.4%, 80 %, and 81.4%) for normal values of (CAVI, cf-PWV, a-PWV, PPamp, AIx, and ABI) respectively. We confirmed the value of (CAVI) as an indicator of cardiovascular disease by investing th e relationship between (CAVI) and several parameters of arterial stiffness including carotid -femoral pulse wave velocity (cf-PWV, r=0.66), arterial stiffness index (AIx, r=0.72), and aortic pulse wave velocity (a-PWV, r=0,96). Pulse pressure amplification showed a negative correlation (PPamp, r=-0.67). A moderate negative correlation was observed with ankle brachial index (ABI, r=-0.38). A weak dependence on different blood pressures at the time of measurement was confirmed, by the coefficients of determination r2 (systolic SBP, 0.08, diastolic DBP, 0.11, mean MBP, 0.10, and pulsed pressures PP, 0.16). The influence of age on arterial stiffness was found with a strong positive correlation between age and cardio-ankle vascular index (CAVI, r=0.88).
Difference between Blood Pressure Measurement during Cuff Inflation and Deflation in the Oscillometric method
(2021) Chabane, Lilia; Omari, Tahar; Latri, hibat Allah; Belatrach, Mohamed Salah
The majority of automatic blood pressure (BP) measurement devices use the oscillometric method made during cuff inflation. However, there is currently little information available concerning the measurements during cuff inflation. This study aimed to provide this information. To achieve this goal, an oscillometic blood pressure device was developed with the ability to drive out the cuff pressure signal and the oscillometric waveforms. The both signals were recorded and processed simultaneously by a specific algorithm to get blood pressure measurements during cuff inflation and deflation. From 9 normotensive cases, the relationship between diastolic blood pressure (DBP), mean blood pressure (MBP) and systolic blood pressure (SBP) measurements during cuff inflation and deflation was compared. The results found confirm a positive linear regression found with a very strong correlation coefficient (R² = 0.97) in the case of MBP. Also, a strong one (R² = 0.81) is found in the case of DBP. However, a moderate R² is found in the case of SBP (R² = 0.60). These results confirm the feasibility of blood pressure measurement during cuff inflation particularly in the estimation of MBP and DBP, which can considerably reduce the duration of measurement from 1 or 2 minute to a few seconds.
Filtering impacts on nonlinear heart rate variability parameters
(IEEE, 2018) Dib, Nabil; Benali, Radhwane; Bereksi Reguig, Fethi; Omari, Tahar
New algorithm for assessment of frequency duration of murmurs using Hilbert-Huang transform
(Springer, 2015) Omari, Tahar; Bereksi-Reguig, Fethi
A new approach for blood pressure estimation based on phonocardiogram
(Springer, 2019) Omari, Tahar; Bereksi‑Reguig, Fethi
Continuous and non-invasive measurement of blood pressure (BP) is of great importance particularly for patients in critical state. To achieve continuous and cuffless BP monitoring, pulse transit time (PTT) has been reported as a potential parameter. Nevertheless, this approach remains very sensitive, cumbersome and disagreeable in ambulatory measurement. This paper proposes a new approach to estimate blood pressure through PCG signal by exploring the correlation between PTT and diastolic duration (S21). In this purpose, an artificial neural network was developed using as input data: (systolic duration, diastolic duration, heart rate, sex, height and weight). According to the NN decision, the mean blood pressure was measured and consequently the systolic and the diastolic pressures were estimated. The proposed method is evaluated on 37 subjects. The obtained results are satisfactory, where, the error in the estimation of the systolic and the diastolic pressures compared to the commercial blood pressure device was in the order of 6.48±4.48 mmHg and 3.91±2.58 mmHg, respectively, which are very close to the AAMI standard, 5±8 mmHg. This shows the feasibility of estimating of blood pressure using PCG
A new methodology of blood pressure measurement through the oscillometric method
(IOP Publishing, 2021) Chabane, Lilia; Omari, Tahar; Benlatreche, Mohamed Salah; Bereksi-Reguig, Fethi
Accurate measurement of blood pressure (BP) is of great importance in a medical diagnostic. It can be obtained by different methods. Nowadays, most BP devices use the oscillometric method which estimates systolic and diastolic BP through different algorithms. Unfortunately, the precision of these devices is always questioned and doctors prefer the use of traditional auscultatory-based methods. In this paper, a new oscillometric method for BP measurement is proposed. In fact, the proposed method is based on the design of a BP device which first detects and maintains the cuff pressure at the level of mean BP then the continuous determination of systolic and diastolic BP. device was assessed by measuring the systolic and diastolic BP on 20 healthy volunteers. The measured pressures were compared with those obtained by two commercially available BP devices. The results show a very high correlation coefficient (r = 0.97), an almost perfect agreement coefficient (kappa = 0.81), and a low mean absolute error (3.43 mmHg). The proposed methodology has a high probability to be complied with the Association for the Advancement of Medical Instrumentation and the British Hypertension Society (Grade A) standards, and can greatly improve the measurement of blood pressure using the oscillometric approach