[Indices of electrocardiogram dispersion mapping during 5-day exposure in dry immersion].

The article presents the results of ECG dispersion mapping in the investigation of 13 young healthy people during 5-d dry immersion (DI). This was the first study of 24-hour variations in dispersion of ECG microoscillations. For this purpose, 20-30 min fragments were "cut out" of every hour of Holter monitoring records to analyze their means after averaging over every 4 hours. Heart rate (HR) and QRS-amplitude were analyzed simultaneously. Index of metabolic adaptation (HR(max/MiO(max)) was calculated. Based on the results, alterations in ECG signal became distinct on DI day-3. They started with a considerable rise of the main ECG amplitudes, especially at night (10.00 p.m. to 6.00 a.m.). The myocardium index makes a significant rise in the period from 10.00 p.m. till 2.00 a.m. However, this index reached its maximum values on DI day-5 in the time intervals from 3.00 till 6.00 p.m. and from 10 p.m. till 10.00 a.m. On DI day-5, of particular interest was a marked HR growth from 10.00 p.m. till 02.00 a.m., and in the post-sleep hours (07.00-10.00 a.m.). Consequently, all this looks like a series engagement of first electrical and then energy metabolism processes in the myocardium reaction to DI. Finally, the increased pulse rate suggests an integral nature of the cardiovascular reaction. This picture of alterations provides grounds for hypothesizing energy metabolism genesis of these reactions.

[Parameters of high definition ECG and dispersion ECG mapping on the background of amlodipin and myostimulation during 7-day dry immersion].

The article presents the results of studying electrophysiological changes in the myocardium of normal human subjects during 7-day dry immersion, and modification of the reaction to immersion by amlodipin and myostimulation. The dry immersion effects on the myocardium generally include a succession of electrophysiological shifts first in the ventricles and then in the left atrium due to, probably, blood pooling in the pulmonary vessels. Myostimulation and amlodipin affect the myocardium reaction visibly suggesting involvement of numerous components of the autonomous and central nervous systems. The positive effect of the pharmaceutical--alleviation of myocardium strain--is a result of amlodipin assistance to the coronary blood flow; however, it has a side-effect on orthostatic stability. The positive action of myostimulation is associated with unloading of the right heart and reflected in changed HD ECG parameters and growth of the "myocardium" index.

[Clinical and prognostic significance of free radical processes in patients with coronary heart disease].

The aim of the work was to evaluate the diagnostic and prognostic value of the characteristics of processes involving free radicals and of high-performance ECG (hpECG) in patients with coronary heart disease (CHD). A new method for early assessment of the severity of myocardial ischemia and its electric remodelling was developed. Malonic dialdehyde levels (MDA) following Cu-induced oxidation during 24 hr were shown to correlate with clinical features of CHD (functional class of angina, hpECG patterns). hpECG characteristics changed parallel to MDA levels, their frequency was related to the severity of CHD. Long-term prognosis of unstable angina (12 month follow-up) was aggravated in patients with MDA level of 100 nmol/ml. MDA concentration and its dynamics correlated with CHD severity and outcome of acute coronary syndrome (ACS): non-Q wave myocardial infarction and angina. All patients with ACS underwent its exacerbation within 5-7 days and had depleted plasma antioxidative system. MDA and hpECG dynamics can be used to evaluate ACS severity and prognosis as a new diagnostic approach to identifying CHD patients with the expected unfavourable outcome of the disease.

[Diagnostic and prognostic validity of high-resolution electrocardiography under the conditions of space flight].

Applicability of high-resolution ECG used in clinics for predicting the probability of life-threatening arrhythmias in cardiovascular patients for the space flight environment was investigated in A 7-d bedrest experiment was to verify HR ECG displayed electrophysiological shifts in myocardial atriums and ventricles. Clearly seen changes in R-amplitude and time course seem to have reflected the volumetric loading and altered sympathetic activity during bed rest QRS-complex had increased the time of low-amplitude signals at the end of the last 40 ms but was short in duration which may point to delayed ventricular depolarization. Prognostically meaningful is exaggerated electrical instability of the myocardium during the standing test on completion of the bedrest period. Results of the investigation allow recommend HR ECG integration into the spacecrew health monitoring system.

Oxidative resistance of the plasma and electrophysiological remodeling of the myocardium in coronary patients.

The diagnostic and prognostic potentialities of the parameters of free-radical processes and high resolution ECG in coronary disease were evaluated. A relationship between oxidative resistance of the plasma (MDA concentration after 24-h copper-induced oxidation) and clinical characteristics of coronary disease (functional class of angina and high-resolution ECG parameters) was detected. Changes in ECG parameters directly correlated with MDA levels, the frequency of their registration reflects the severity of coronary disease. The absolute values of ECG, MDA, and their dynamics correlated with the severity of coronary disease and outcome of acute coronary syndrome, the prognosis was unfavorable for patients with MDA level >100 nmol/ml. The level of MDA increased by days 5-7 of observation in all patients with acute coronary syndrome, indicating exhaustion of the plasma antioxidant system during exacerbation of the coronary syndrome. Hence, evaluation of the plasma oxidative resistance and high resolution ECG can serve as a new diagnostic complex approach for detecting coronary patients with an unfavorable prognosis.

[A system of electrode arrangement for measurement of the coordinates of sources in the myocardium area].

A system of electrode arrangement for localization of zones of small depolarization abnormalities in human myocardium is suggested. Standard electrodes R, L, F and Frank electrodes H, M compatible with standard methods of examination. The total number of electrodes in the system is 15. A technique for reconstruction of the coordinates and orientation angles of the abnormality sources from measured electrode potentials is suggested. Statistical modeling is used to assess the dependence of the reconstruction error on the source position and orientation. The maximal error of coordinate measurement is found to be approximately 1.5 mm; average error, 0.75 mm.

[Correlations between electrophysiological myocardial remodeling and parameters of free radical oxidation in patients with various forms of ischemic heart disease].

AIM: To investigate potentialities of a novel biochemical test assessing oxidative resistance of plasma as a marker of ischemic damage to the myocardium and to study this marker correlation with high-performance ECG parameters reflecting electrophysiological remodeling of the myocardium in patients with ischemic heart disease (IHD). MATERIAL AND METHODS: A total of 145 IHD patients entered the trial: 32 patients free of effort angina, 67patients with stable effort angina of functional class (FC) II-III, 56 patients with acute coronary syndrome (ACS) and 32 healthy controls. ACS patients were examined according to the following protocol: stage 1--6-12 hours since the disease onset, stage 2--at the end of the first 24 hours, stage 3--day 5-7 of the disease. In ACS patients the following outcomes (end points) were evaluated: recurrent myocardial infarction (MI), hospitalization because of exacerbation of IHD, documented potentially harmful arrhythmias and death within 1 year. High-performance ECG and a novel biochemical test of plasma oxidizability were used. The latter was determined by accumulation of malonic dialdehyde after 24 hours of incubation with 20 mcM of copper sulphate. RESULTS: A correlation was found between activity offree radical processes and electrophysiological remodeling of the myocardium by high-performance ECG. Amplitude and temporal characteristics of QRS complex and P wave can be used for follow-up of progression and severity of IHD in addition to standard electrocardiography. CONCLUSION: Unidirectional changes of high-performance ECG, plasma oxidizability and severity of IHD course allow using them as novel diagnostic tests of ischemic lesion and electrophysiological remodeling of the myocardium, for estimation of IHD severity.

[Relationships between the content of circulating immune complexes, the concentration of serum immunoglobulins and the titers of specific antibodies in patients with tick-borne encephalitis]. / Vzaimootnosheniia mezhdu soderzhaniem tsirkuliruiushchikh immunnykh kompleksov, kontsentratsiei syvorotochnykh immnoglobulinov i titrov spetsifitseskikh antitel u bol'nykh kleshchevym éntsefalitom.

In the blood serum of tick-borne encephalitis (TBE) patients the detection rate and concentration of circulating immune complexes, as well as the content of serum IgA, IgM and IgG, were evaluated. The formation of immune complexes was found to depend on IgM and IgG specific antibodies to TBE virus, the period of the disease and the clinical form of virus infection.

[Relation between resistance to oxidation and cholesterol acceptance of high density lipoproteins in patients with ischemic heart disease]. / Vzaimosviaz' mezhdu okislitel'noi ustoichivost'iu i kholesterin-aktseptornoi sposobnost'iu lipoproteinov vysokoi plotnosti u bol'nykh ishemicheskoi bolezn'iu serdtsa.

Cholesterol (CH) acceptance ability of high density lipoproteins (HDL) was assessed in 43 ischemic heart disease (IHD) patients, including patients with post-infarction cardiosclerosis and class II-III effort angina. CH acceptance ability of HDL was measured as increment of HDL CH after incubation with artificial CH-containing system. Oxidabilities of HDL and total plasma were estimated by quantitation of lipid peroxidation products (hydroperoxides and thiobarbituric acid-reactive substances - TBARS) after incubation with Cu(2+) ions. HDL fraction (after apo B lipoproteins removal) of IHD patients appeared to include 2 times less additive CH compared with donor's HDL despite lower (-12%) HDL CH level. Negative correlation (r =-0.38, p<0.05) existed between formed TBARS in HDL and HDL CH acceptance. In total plasma of IHD patients elevation of both formed TBARS and particularly hydroperoxides was observed. Parallelism between decrease of CH acceptance by HDL, oxidability of HDL and of total plasma testifies on weakness not only of CH-accepting, but also of antioxidant HDL functions in IHD patients.

[The way of evaluation of cholesterol accepting capacity of plasma high density lipoproteins]. / Sposob otsenki kholestrin-aktseptornoi emkosti lipoproteinov vysokoi plotnosti plazmy krovi.

The simple way of quantitative evaluation of high density lipoproteins (HDL) capacity to absorb additive cholesterol quantity is proposed. It allows to evaluate indirectly intensity of the first, rate limiting stage of reverse cholesterol transport its accepting from the cells by means of HDL. The way includes the usage of stable artificial cholesterol donor--cholesterol covered inert polymer particles, which are than more convenient, than cell culture use. The total HDL rough fraction (i.e. serum after apoB lipoproteins removal) was shown to include more than 50% cholesterol in addition to yet presenting amount. But this ability is sharply reduced, or sometimes even is completely absent, in HDL of 63 coronary heart disease (CHD) patients (as compared with 41 healthy donors). This difference of potential cholesterol accepting capacity is revealed even at the same initial HDL concentrations. The negative correlation (r = - 0.32, p < 0.05) between this HDL property (delta HDL cholesterol) and their oxidability in the ions Cu2+ presence was observed. This underlines atherogenic role of HDL oxidability. The treatment of patients by phospholipids (as Lipostabyl) resulted to recovery of HDL cholesterol accepting capacity. The possible mechanisms of junction of this HDL activity with their oxidability are discussed, as well as necessity of evaluation of HDL properties and reverse cholesterol transport for the choice of care strategy of CHD patients.

[Effect of metoprolol CR/XL on remodeling of the heart and cardiac rhythm disturbances after myocardial infarction in patients with chronic heart failure]. / Vliianie metoprolola CR/XL na postinfarktnoe remodelirovanie i narusheniia ritma serdtsa u bol'nykh s khronicheskoi serdechnoi nedostatochnost'iu.

Metoprolol succinate was given to 60 patients with class I-III heart failure and ejection fraction <45% after myocardial infarction. Forty seven patients (mean age 59.3+/-9.8 years) completed 6 months of therapy. Dynamics of ventricular arrhythmias was assessed by Holter ECG monitoring, registration of parameters of high resolution ECG and heart rate variability. and echocardiography. Functional class of heart failure decreased in 93%, that of angina - in 55% of patients. Antiarrhythmic effect was achieved in 72% of patients. This was associated with diminishment of left ventricular volumes and increased ejection fraction, shortening of TotQRSF, and improvement of autonomic regulation of cardiac action. No dynamics of myocardial contractility and electrophysiological remodeling occurred in patients without antiarrhythmic effect.

[Role of sialic acids in the immune response formation in tick-borne encephalitis]. / Rol' sialovykh kislot v formirovanii immunnogo otveta pri kleshchevom éntsefaliti.

The content of individual forms of sialic acids and total sialic acids in the lymphocytes of tick-borne encephalitis patients has been studied. The level of sialic acids has been found to depend on the clinical form of the disease and on the content of specific IgM and IgG to tick-borne encephalitis virus. Similar dependence has been established with respect to total sialic acids in lymphocytes.

[Parameters of variation pulsometry, Q-T interval dispersion and frequency of occurrence of late potentials in acute myocardial infarction]. / Parametry variatsionnoi pul'sometrii, dispersiia intervala Q-T i chastota registratsii pozdnikh potentsialov pri ostrom infarkte miokarda.

Registration of standard and high-resolution EGCs, echocardiography in 90 ischemic heart disease (IHD) patients on myocardial infarction week 2 to 6 has demonstrated that deterioration of local myocardial contractility and development of left ventricular dilation increase frequency of late ventricular potentials and worsen parameters of high-resolution ECG. Left ventricular dysfunction is associated with defects in autonomic regulation of cardiac activity. Diminished myocardial contractility had no significant effect on dispersion of repolarisation.

Assessment of electrophysiological state of heart in astronauts in terms of decartographic and conventional electrocardiographic characteristics.

Long-term observation of the heart state during specialized professional activities plays an important part in preventive medicine. This study is aimed at assessment of electrophysiological state of heart in astronauts by common electrocardiography, vectorcardiography, and dipole electrocardiotopography (DECARTO technique). The subjects observed were two astronauts performing a long-term flight at the Mir orbital station. DECARTO technique was used to obtain an intelligible-pictorial representation of the data in the form of so-called decartograms for visual and quantitative analysis. The observations showed rather stable chronotopography of the heart depolarization process. However, there was an increase of the maximal magnitude of the electric heart vector and a decrease of the ventricular gradient vector in the middle part of the flight. Just upon landing, a pronounced decrease of the ventricular gradient magnitude, followed by a fast restoration of its value was observed in both subjects. The DECARTO technique used in combination with vectorcardiography facilitated the detailed visual analysis of the electrocardiographic data. (Fig. 3, Ref. 3.)

[The analysis of systemic hemodynamics and of myocardial functional status in patients in critical states]. / Analiz sistemni gemodinamiki i funktsional'nogo sostoianiia miokarda u bol'nykh v kriticheskikh sostoianiiakh.

Timely diagnosis of disorders of the pumping function of the heart and its inotropic state, strained compensation, and failure of the compensatory potential are important for selecting the treatment strategy and predicting the disease course in critical patients. This paper presents the results of many-year investigations in this field. The contribution of right-ventricular insufficiency to the development of circulatory disorders is validated, as is the effect of artificial ventilation of the lungs on the function of the myocardium. Relationship between the severity of hemodynamic disorders and pathological process is described. The author validates the use of test exposures and functional tests in intensive care departments in order to assess the functional insufficiency and reduction of the reserve potential of the right and left heart. The potentialities of spectral analysis of the electrocardiographic signal in the early diagnosis of myocardial dysfunction and prediction of the disease course is shown.

[Organizational problems of the production of biological preparations of blood]. / Organizatsionnye problemy proizvodstva biopreparatov krovi.

The trend of the incidence of tick-borne encephalitis makes one pay attention to the production of blood biological preparations. A detailed programme for improving the production process, which is included into the federal and republican programmes, is outlined.

High resolution electrocardiographic abnormalities as possible indexes of electric instability of the myocardium.

OBJECTIVE: To evaluate the signal-averaged high resolution electrocardiogram in the time domain and the frequency domain in various cardiac patients. DESIGN: Patients in seven clinical diagnostic categories were compared with a healthy control group. PATIENTS AND METHODS: The control group consisted of 70 clinically healthy persons. The 525 cardiac patients were divided as follows: group 1, 29 patients with surgically corrected mitralvalvular disease; group 2, 42 postinfarction patients with-bypass grafting; group 3, 57 patients with ventricular tachycardia; group 4, 198 patients with medically treated angina; group 5, 63 patients with hypertension; group 6, 46 patients with paroxysmal atrial fibrillation; and group 7, 90 patients with acute pulmonary insufficiency. The Frank orthogonal leads were used to derive the signal-averaged electrocardiogram in the usual manner by averaging over 200 complexes. Time domain and frequency domain data were recorded for both the P wave and the QRS complex. RESULTS: Ventricular late potentials were found most often in patients with postinfarction ventricular tachycardia (59%). The prevalence of ventricular late potentials in the mitral valvular disease group increased from 45% to 70% after surgery; in the bypass grafting group it also increased. Spectral temporal mapping revealed a substantial decrease of the total spectral power in the bypass grafting group, to 129 +/- 19 microV2/Hz compared with the preoperative period (205 +/- 16 microV2/Hz). The high frequency power decreased, so the ratio of low frequency to high frequency power increased. A significant correlation was found between the root-mean-square signal in the last 40 ms of the QRS complex and each of the amplitude parameter, the frequency domain localization and time domain localization of the power density peaks. CONCLUSIONS: High resolution electrocardiography including time domain and frequency domain analyses may prove helpful in diagnosis and management.