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Kiselev A.R.,Saratov State Medical University | Mironov S.A.,Central Clinical Military Hospital | Karavaev A.S.,RAS Institute of Radio Engineering and Electronics | Kulminskiy D.D.,RAS Institute of Radio Engineering and Electronics | And 5 more authors.
Physiological Measurement | Year: 2016

We compare the spectral indices of photoplethysmogram variability (PPGV) estimated using photoplethysmograms recorded from the earlobe and the middle fingers of the right and left hand and analyze their correlation with similar indices of heart rate variability (HRV) in 30 healthy subjects (26 men) aged 27 (25, 29) years (median with inter-quartile ranges) at rest and under the head-up tilt test. The following spectral indices of PPGV and HRV were compared: mean heart rate (HR), total spectral power (TP), high-frequency (HF) and low-frequency (LF) ranges of TP in percents (HF% and LF%), LF/HF ratio, and spectral coherence. We assess also the index S of synchronization between the LF oscillations in HRV and PPGV. The constancy of blood pressure (BP) and moderate increase of HR under the tilt test indicate the presence of fast processes of cardiovascular adaptation with the increase of the sympathetic activity in studied healthy subjects. The impact of respiration on the PPGV spectrum (accessed by HF%) is less than on the HRV spectrum. It is shown that the proportion of sympathetic vascular activity (accessed by LF%) is constant in the PPGV of three analyzed PPGs during the tilt test. The PPGV for the ear PPG was less vulnerable to breathing influence accessed by HF% (independently from body position) than for PPGs from fingers. We reveal the increase of index S under the tilt test indicating the activation of interaction between the heart and distal vessels. The PPGV spectra for finger PPGs from different hands are highly coherent, but differ substantially from the PPGV spectrum for the ear PPG. We conclude that joint analysis of frequency components of PPGV (for the earlobe and finger PPGs of both hands) and HRV and assessment of their synchronization provide additional information about cardiovascular autonomic control. © 2016 Institute of Physics and Engineering in Medicine. Source


Hovhannisyan S.R.,Central Clinical Military Hospital | Hovhannisyan S.R.,Yerevan State Medical University | Khachatryan G.E.,Yerevan State Medical University | Mashinyan K.A.,Yerevan State Medical University | Gasoyan H.S.,Yerevan State Medical University
New Armenian Medical Journal | Year: 2012

Congenital malformations of the teeth and maxillofacial region are ranked second in terms of all congenital anomalies. In general, congenital palatal defects, are treated in childhood by means of surgery. Unfortunately, sometimes, even after several operations, the massive cleft of the palate cannot be closed. Some years later the patient will suffer from the defect, which is usually complicated by scars due to numerous previous operations. This article presents a case report on the use of implants in prosthetic treatment of congenital palatal defects. Studies showed that one of each 800-1000 newly-born children has a cleft of upper lip or cleft palate. In some countries the cleft lip and cleft palate prevalence rate increases to 1 per 300 births. Cleft lips make 20-30% and cleft palates reach 70-80% of all congenital facial deformities. Clefts of the lip and palate are commonly combined [Mossey P., Castilla E., 2001; Mastroiacovo P., 2010]. Unilateral cleft of the lip usually occurs on the left side. It is important to mention that, as a rule, these defects are treated in childhood by means of surgery. The reconstructive operations are usually performed stage-by-stage to obtain satisfactory results, because there is a deficiency of hard and soft tissues in the maxillofacial region. Sometimes, even after several operations, the massive cleft of the palate cannot be closed. Some years later the patient will suffer from the defect, which is usually complicated by scars due to numerous previous operations [Global Strategies, 2001]. If the operation is not performed at the proper time of child development, the formation of t jaw is complicated and there will be deficient sagital and transverse growth of the maxilla. The situation can be also complicated in cases of edentulousness. Source


Kiselev A.R.,Saratov State Medical University | Shvartz V.A.,The Surgical Center | Karavaev A.S.,Chernyshevsky Saratov State University | Mironov S.A.,Central Clinical Military Hospital | And 3 more authors.
Open Cardiovascular Medicine Journal | Year: 2016

Objective: The aim of the present study was to assess the features of dynamics of cardiovascular autonomic indices and correlations between them during the two-hour immobilization test in healthy subjects. Methods: Photoplethysmogram (PPG) and electrocardiogram were recorded simultaneously during the two-hour immobilization test in 14 healthy subjects (5 men and 9 women) aged 29±5 years (mean±SD). Dynamics of heart rate variability (HRV) power spectrum in high-frequency and low-frequency ranges (in ms2 and percents of total spectral power), mean heart rate (HR), and index S of synchronization between 0.1-Hz rhythms in PPG and HR were analyzed. Results: Individual dynamics of all studied cardiovascular autonomic indices during the two-hour immobilization test was unique in each healthy subject. Two groups of healthy subjects were identified basing on individual features of autonomic control. The group with initial low level of index S maintained the low level of S during the two-hour immobilization test. The group with initial high index S maintained the high level of S only during the first 100 minutes of test. During the last 20 minutes of test, index S was similar in both groups. Many cardiovascular autonomic indices correlate between themselves for an individual subject, but they do not correlate between the subjects. Multiple regression analysis in each subject has shown a high correlation between mean HR and all other studied autonomic parameters in 57% of subjects (multiple R>0.9, P<0.05). For 204 records analyzed without taking into account the individual features of subjects, the above mentioned correlation was smaller (multiple R=0.45, P<0.001). Index S was found out to be the most independent one among the autonomic indices. Conclusion: Cardiovascular autonomic control is characterized by a pronounced variability among healthy subjects and stability in time in each subject. We have not found any regularity in variation of cardiovascular autonomic indices, which is common for the entire group of healthy subjects during the two-hour immobilization test. Mean HR is a summary index of efficiency of heart autonomic control. Index S is the most independent cardiovascular autonomic parameter. © Kiselev et al.; Licensee Bentham Open. Source

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