[Heart rate turbulence and T-wave alternans as markers of risk of sudden cardiac death in patients with hypertrophic cardiomyopathy].

AIM: to study microvolt T-wave alternans (mTWA) and heart rate turbulence (HRT) in patients with hypertrophic cardiomyopathy (HCMP). MATERIAL AND METHODS: We examined 50 patients with HCMP: 15 (28%) with obstructive form, 23 (46%) with major risk factors of sudden cardiac death (SCD), 7 (14%) with left ventricular thickness more or equal 3 cm, 6 (12%) with family history of SCD, 16 (32%) with attacks of nonsustained ventricular tachycardia (NVT), 5 (10%) with episodes of syncope. Control group comparable by age and gender composition comprised 50 persons without cardiovascular diseases. All patients were subjected to 24-hour ECG monitoring with registration of parameters of variability and HRT (turbulence onset [TO], turbulence slope), maximal mTWA values, mTWA at heart rate 100 bpm, mTWA at 05.00 AM (mTWA05:00). RESULTS: Patients with HCMP compared to controls were characterized by significantly higher values of mTWA05:00 (19 [13;30] and 9 [4;15] mcV, respectively, p<0.001). There was tendency to greater prevalence of pathological HRT values in patients with HCMP compared with healthy subjects (p=0.083). Prevalence of pathological TO values among patients (16%) was significantly higher than among controls (2%), (p<0.05). CONCLUSIONS: Compared to healthy subjects patients with HCMP were characterized by higher mTWA05:00 and higher prevalence of pathological values of TO. mTWA was directly related to numbers of ventricular extrasystoles and NVT attacks. Patients with attacks of NVT compared with those without had lower SDNN pNN50.

[Tissue and cell interactions in the oral mucosa after cytostatic drugs administration].

In the preceding work ("Morphology", 2011, issue 2), the regularities of oral mucosal (OM) epithelium injury after the cytostatic drug (CSD) treatment and its further regeneration, were reviewed. This paper presents the systematized summary of current literature data and the authors' own findings on the regularities of CSD effect on non-epithelial OM cell populations and their interactions with each other and the epithelium. The changes of intraepithelial tissue homeostasis, associated with CSD effect on intraepithelial lymphocytes, granulocytes, dendritic antigen presenting cells and melanocytes, interacting with epitheliocytes, are described. The data are presented, indicating that along with the epithelium, the cell populations of lamina propria and submucosal connective tissue, as well as the small blood vessels, are important targets of CSD in the OM tissues. The concept of a unifying model, describing tissue, cellular and molecular mechanisms of the oral mucositis development after CSD treatment, is reviewed.

[Injury and reparative regeneration of the oral mucosal epithelium after cytostatic drugs administration (tissue, cell and molecular mechanisms)].

This paper presents the systematized summary of current literature data and the authors' own findings on the regularities of human and animal surface oral mucosal epithelium (OME) injury caused by cytostatic drugs (CSD) administration, and on the ways of its regeneration after the cytostatic chemotherapy (CSCT) discontinuation. Tissue, cell and molecular mechanisms of CSCT effects on OME, are described. The direct effects of CSD included the epithelial layer attenuation with the derangement of its architecture, epitheliocyte proliferation suppression, apoptosis activation, and differentiation disturbances (involving the broad spectrum of cytological, cytochemical, ultrastructural and molecular-biological changes). In severe cases, these processes resulted in the loss of the epithelial layer integrity with the development of ulceration. Complete epithelial regeneration requires a long period after the CSCT discontinuation. Indirect effects of CSD on OME are associated with the microbial invasion and the diffusion of microbial vital activity products into the epithelium with concurrent leukopenia, immunosuppression and decreased salivary secretion.

[Morpho-functional characteristic of oral mucosal epithelium after treatment with a cytostatic drug].

The effect of cytostatic drug cyclophosphamide (CY) on lingual epithelium was studied in 90 female mice using histological, morphometric, quantitative histochemical and immunohistochemical methods. CY (400 mg/kg) was injected intraperitoneally three times with a 48 h interval. Material was obtained 2 days after injections and 10-20 days after their discontinuation. CY treatment was shown to result in the damage of both surface epithelium of the tongue and the epithelium of minor lingual salivary glands. Damage to the surface epithelium was more pronounced on the ventral surface of the tongue and was associated mainly with the disturbances of its proliferation. Changes were less severe on the dorsal surface and were seen as the disturbances of epithelial differentiation and desquamation. Glandular epithelium was damaged to a lesser extent than the surface one, with serocytes being more sensitive to the cytotoxic injury than mucocytes. After cytostatic drug discontinuation, the tendency for the normalization of the epithelial characteristics was noted. Most persistent changes in the surface epithelium were found on the dorsal surface of the tongue and in the glandular epithelium--in the serous secretory portions of the salivary glands.

[The use of positron emission tomography for noninvasive diagnosis of mitochondrial dysfunction and assessment of myocardial compensatory reserve in children with cardiomyopathies]. / Neinvazivnaia diagnostika mitokhondrial'noi disfunktsii i otsenka kompensatornykh vozmozhnostei miokarda u detei s kardiomiopatiiami s pomoshch'iu pozitronnoi émissionnoi tomografii.

BACKGROUND: Recent experimental and clinical studies have shown that cardiomyopathy (CMP) can be associated with disorders of oxidative metabolism in cardiomyocyte mitochondria. These disorders are connected with deficit of enzymes and complexes of electron transfer chain, and can constitute pathogenetic base of the disease. AIM. To study myocardial metabolism in children with cardiomyopathies using positron emission tomography (PET). METHODS: PET studies were carried out in 17 patients (pts.) aged 3-13 years (mean age 7,5-/+3,1) with CMP: hypertrophic (HCMP, n=4), dilated (DCMP, n=9), after radical correction of tetralogy of Fallot (TF, n=4). The dynamic study with [1-11C]-acetate was performed for evaluation of Krebs cycle activity. Rate constant (kmono) and [11C]-activity elimination half-time (T1/2) were calculated using myocardial time-activity curve. Myocardial perfusion was assessed with [13N]-ammonia, glucose metabolism - with [18F]-fluorodeoxyglucose. RESULTS: Patients with HCMP: left ventricular (LV) perfusion was normal, Krebs cycle activity - decreased; glucose utilization was increased in comparison with normal level in 2, and was normal in 2 other children. Patients with DCMP: LV perfusion was normal; Krebs cycle activity in LV was decreased in 6 and normal - in 3 pts. Overall 2 pts. with CMP had focal perfusion defects. More pronounced decrease of Krebs cycle activity in these regions compared with other LV parts implied development of ischemic injuries. Decrease of glucose utilization in these fields indicated that the injuries were irreversible. Patients with TF: 3 pts. had normal perfusion and Krebs cycle activity; 1 patient with severe hemodynamic disorders had decreased perfusion, glycolysis and Krebs cycle activity in both ventricles indicative of the presence of myocardial dystrophic changes. CONCLUSION: Despite normal perfusion children with cardiomyopathy had decreased Krebs cycle activity (mitochondrial dysfunction). Decrease in oxidative metabolism could be compensated by increased glycolysis.

[Mitochondrial nature of cardiomyopathies in children (analysis of skeletal muscle biopsies)]. / Mitokhondrial'naia priroda kardiomiopatii u detei (analiz bioptatov skeletnykh myshts.

Morphological characteristics of the skeletal muscle biopsies from 10 children with idiopathic dilatational and hypertrophic cardiomyopathies are described. Methods of light and electron microscopy, histochemistry (mitochondrial enzymes, glycogen, lipids, calcium), morphometry and statistics were used. The presence of specific and nonspecific signs of systemic mitochondrial insufficiency, the character of histochemical distribution of the energetic substrates and the calcium suggest that this insufficiency is the basis of cardiomyopathies pathogenesis.

[The psychological characteristics of adolescents with ischemic heart disease in their anamnesis and their linkage to the lipoprotein spectrum indices]. / Psikhologicheskie osobennosti podrostkov s ishemicheskoi bolezn'iu serdtsa v anamneze i ikh sopriazhennost' s pokazateliami spektra lipoproteidov.

A psychological survey (MMPI, Wolff, Rosenzweig, Spielberger, Eysenck tests) of 70 adolescents with family history of coronary heart disease established the following personality traits in them: activity, leadership inclinations, extroversion, impulsiveness, heteroaggressiveness coupled with inner strain, anxiety. The anxiety, heteroaggression, extroversion correlated with atherogenic changes in lipoprotein spectrum.

[Characteristics of the cardiovascular system in children with primary arterial hypotension]. / Kharakteristika serdechno-sosudistoi sistemy u detei s pervichnoi arterial'noi gipotoniei.

Overall 120 children aged 12 to 15 years with primary arterial hypotension and different variants of the disease course (grave, of medium gravity or mild) were examined. The control group was made up to 50 normal children. The program of the examination included electrocardiography, echocardiography, tetrapolar chest rheography and bicycle ergometry. It has been established that in children with arterial hypotension, the intracardiac hemodynamics undergoes compensatory adaptive reconstruction characterized by the enhancement of contractile and pump functions of the myocardium combined with the increased relaxation capacity. The central hemodynamics is characterized by the lowering of the general peripheral vascular resistance. The functional potentialities of the cardiovascular system decline, manifesting in the form of a decrease of exercise tolerance in association with energy losses necessary for its performance. The use of bicycle ergometry made it possible to delineate dysadaptation reactions of arterial pressure to exercise, modified by hereditary factors.

[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.