[Characteristics of circadian variability of heart rate during Holter monitoring]. / Kharakteristika tsirkadnoi variabel'nosti chastoty serdechnykh sokrashchenii v period kholterovskogo monitorirovaniia.

24-hour Holter monitoring of 60 healthy children aged 3 to 15 years provided criteria for assessing the circadian heart rate (HR) variations as a measure of alterations occurred in autonomic heart rhythm control. Specific HR dynamics during their sleep is described, which involves changes in steady-state rhythm and higher dispersion periods associated with the alternation of slow and fast sleep phases. Sex- and age-related HR features are defined during 24-hour monitoring.

[Changes in central hemodynamics as a risk factor of the development of ischemic heart disease in adolescents with aggravated heredity of atherosclerosis]. / Izmenenie tsentral'noi gemodinamiki kak faktor riska razvitiia ishemicheskoi bolezni serdtsa u podrostkov s otiagoshechennoi nasledstvennost'iu po aterosklerozu.

The authors provide the data on the central hemodynamics, blood plasma lipoproteins and apoproteins in 101 adolescents with aggravated heredity as regards coronary heart disease and in healthy adolescents of the same age serving as control. The hypokinetic variant of circulation is demonstrated to be coupled with the atherogenic nature of the lipoprotein and apoprotein spectra and heredity to contribute greatly to the traits under study. Criteria for the adolescents' inclusion into the group at the highest risk for early development of atherosclerosis are described.

[The role of genetic and environmental factors in phenotypic variability of arterial pressure and body weight and their interconnection (a family study)]. / Rol' geneticheskikh i sredovykh faktorov i fenotipicheskoi izmenchivosti arterial'nogo davleniia i massy tela i v ikh vzaimosviazi.

Contribution of genetic and environmental factors into phenotypic variability of blood pressure and body mass as well as into phenotypic correlation between these traits was defined. It was shown that additive genetic determinant is responsible for considerable level of blood pressure and body mass variability. Those common environmental factors are of importance which operate within the limits of one generation. Maternal effect of systolic and diastolic blood pressure variability is negligible. The correlation between systolic and diastolic blood pressure is determined both by environmental and genetic factors, whereas that between blood pressure and body mass is mediated by only environmental factors. The contribution of environmental factors into correlation between blood pressure and body mass lessens with age. The results obtained may be applied in development of population and individual programmes for preventing cardiovascular diseases.

[Chronic nonparoxysmal supraventricular tachycardia in children and adolescents]. / Khronicheskaia neparoksizmal'naia supraventrikuliarnaia takhikardiia u detei i podrostkov.

An examination was performed in 111 children and adolescents with recurrent and sustained chronic nonparoxysmal tachycardias (CNPT). ECG and electrophysiological studies showed that ante- and retrograde conduction along the accessory atrioventricular junction was the most common mechanisms of arrhythmia. Holter monitoring revealed a high rigidity of cardiac rhythm in patients with sustained CNPT. Criteria for the development of arrhythmogenic cardiac dilatation were developed. In recurrent CNPT, there was a correlation between the paroxysms of ECG slow-wave activity and the "salvos" of tachycardia and a predominance of vagal effects on the heart. A new approach to the treatment of children with CNPT was proposed, which involved the correction of pathogenetic mechanisms. Indications for the usage of antiarrhythmic agents such as cordarone and a cardiac surgeon's advice were formulated. The efficiency of the therapy was achieved in 82% of the children as shown by a follow-up.

[Role of genetic and environmental factors in the determination of body weight and skinfold thickness in children having different blood pressure (a familial study)]. / Rol' geneticheskikh i sredovykh faktorov v determinatsii massy tela i tolshchiny kozhnykh skladok u detei s raznym urovnem arterial'nogo davleniia (semeinoe issledovanie).

Based on intrafamilial correlations, a component genetic analysis was used to evaluate the contribution made by genetic and environmental factors to variance in body weight and skin fold thickness in children who had various blood pressure. In children with initially elevated and normal blood pressures, the phenotypic variation in the body weight and adipopexia is largely determined by genetic factors, whereas in those with initially lower blood pressure, the phenotypic variation in the above parameters is greatly affected by environmental factors, mainly by those of occasional nature. The findings provide evidence for a differential approach to the primary prevention of hyper- and hypotension in children and adolescents.

[Characteristics of 24-hour ECG and the regulation of cardiac rhythm in adolescents]. / Kharakteristika sutochnoi EKG i reguliatsii serdechnogo ritma u podrostkov.

Holter 24-hour monitoring was performed in 50 healthy subjects aged 11-15 years. Daily changes and standard values of heart rate (HR), P-R and Q-T intervals, P, R, T wave amplitudes, ST segment displacement were determined. All the patients under study exhibited sinus arrhythmia, pacemaker migration periods, short cardiac rhythm pauses (up to 1.5 s). Three adolescents were recorded to have Degree I atrioventricular block at night, 3 presented with rare (up to 2 per min) supraventricular contraction beats, 1 had a nocturnal transient Wolff-Parkinson-White syndrome. Despite HR at night, there were periods of Q-T interval prolongation. Daily changes in the neurohumoral regulation of the heart and its relation to the occurrence of various electrocardiographic events were determined.

[The role of genetic and environmental factors in serum lipid changes in children with various levels of arterial blood pressure (a family study)]. / Rol' geneticheskikh i sredovykh faktorov v izmenchivosti soderzhaniia lipidov syvorotki krovi u detei s raznymi urovniami arterial'nogo davleniia (semeinoe issledovanie).

Blood lipid and lipoprotein concentrations were measured in proband children with different levels of arterial pressure and in their relatives in the populational familial study. Based on intrafamilial correlations the component analysis of the phenotypic dispersion of total cholesterol, high density lipoprotein cholesterol and triglyceride concentrations was performed. Qualitative and quantitative differences were shown to exist in genetic and environmental determinants of lipids and lipoproteins in the families of probands with low, high and normal levels of arterial pressure.

Holter monitoring in the long QT syndrome of children and adolescents.

Results of Holter monitoring (HM) of ECG in 45 patients with long QT syndrome (LOTS) and 26 healthy control children are presented. 15 patients had a history of syncopal attacks (group I), other patients were symptomless (group II). Heart rate-corrected QT interval (QTc) on standard resting ECG exceeded 460 ms in 73.3% of patients in group I and in 44.8% of group II patients. On Holter monitoring, it was present in 100% of group I and 83.9% of group II patients. T wave alternation was registered in 66.6% of group I and 56.7% of group II patients. Ventricular arrhythmia was not found on standard resting ECG in any of the examined children, whereas Holter monitoring revealed ventricular extrasystoles in 53.3% of group I and 6.7% of group II patients (p less than 0.05). In one case early ventricular extrasystoles accompanied an attack of ventricular tachycardia. Mathematical analysis of 24-h extracardial heart rhythm regulation revealed its disturbance in LQTS patients compared to healthy children, as well as asthenic signs in the sympathetic nervous system. These changes were more pronounced in patients with a more severe course of the disease (group I).

[Role of genetic and environmental factors in determination of arterial blood pressure level]. / Rol' geneticheskikh i sredovykh faktorov v determinatsii urovnia arterial'nogo davleniia.

Three groups of families with different initial levels of arterial pressure in proband children were examined. The relationship was established between the levels of arterial pressure in children and those in their relatives of the first degree of kinship. Based on intrafamilial correlations, the phenotypic dispersion of systolic and diastolic arterial pressure was analyzed. It has been shown that as compared to the genetic factors, the environmental factors play a greater role in arterial pressure variability.

[Current approaches to the study of psychosomatic effects on the pathology of the cardiovascular system in children]. / Sovremennye podkhody k izucheniiu psikhosomaticheskikh vliianii na patologiiu serdechno-sosudistoi sistemy u detei.

A total of 131 children suffering from hereditary predisposition to coronary heart disease, 70 subjects with dysfunction of the and 120 subjects with dysfunction of the vegetative nervous system and low blood pressure were examined. The examination of the children included a study of the cardiovascular system and the vegetative nervous system as well as psychological studies. The cardiovascular system response to the psychoemotional teleplay test was measured in addition. It has been demonstrated that the psychoneurosomatic interrelations are implicated in the occurrence of the main most prevalent cardiovascular diseases in children. This determines approaches to the treatment and prevention of arterial high and low blood pressure and cardiac rhythm disorders.

[Changes in phospholipid composition of high density lipoproteins in children as a possible precursor of the development of ischemic heart disease]. / Izmenenie fosfolipidnogo sostava lipoproteidov vysokoi plotnosti u detei kak vozmozhnyi predvestnik razvitiia ishemicheskoi bolezni serdtsa.

The proportion of apoprotein-AI (apo-AI) phospholipids (PL) and HDLP phospholipid spectrum were determined in addition to principal coronary risk factors; cholesterol (CS), triglycerides (TG) and high-density lipoprotein (HDLP) CS, in high-risk children, whose parents had survived myocardial infarction at a young age, and also in children with vegetovascular dystonia and a control group. It is demonstrated that children with relatively low percentage of lecithin in HDLP, in the absence of changes in CS, TG, apo-B and apo-AI, and HDLP CS, could be found in all the examined groups, and were particularly numerous in the high-risk group. Correlations coefficients for the HDLP PL percentage in the father-child, mother-child and father-mother pairs were estimated, revealing a positive correlation with respect to lecithin in these pairs, an evidence of the contribution of the general familial environment to the variability of the parameter in question in the examined groups. Different correlations were demonstrated between lecithin/sphingomyelin and lecithin/kephalin ratios in boys and girls from the control and high-risk groups.

[Blood coagulation and fibrinolysis in ischemic heart disease. The relationship to risk factors]. / Sostoianie gemokoaguliatsii i fibrinoliza pri ishemicheskoi bolezni serdtsa. Vzaimosviaz' s faktorami riska.

The data on blood coagulation and fibrinolysis in patients with coronary heart disease are reviewed. The relationship of the coagulating and fibrinolytic systems with cardiovascular risk factors is analysed.