[Arterial hypertension in metabolic syndrome: pathophysiological aspects].

Arterial hypertension (AH) is one of the basic components of metabolic syndrome that is caused by four factors: autonomic sympathetic dysfunction; activation of the hypothalamic-pituitary-adrenal axis; that of the renin-angiotensin-aldosterone system; and endothelial dysfunction (ED). AH is a slowly progressive hemodynamic disease, the natural course of which is characterized by not only elevated blood pressure (BP), but also by left ventricular hypertrophy, arterial remodeling, and a progressive increase in total peripheral resistance. ED and arterial remodeling play a key role in the pathogenesis of AH in metabolic syndrome. Remodeling of resistant arteries raises peripheral resistance and stabilizes BP and that of large arteries increases their stiffness and a reflected wave, resulting in increased pulse BP, systolic BP, and enhanced left ventricular hypertrophy. Insulin resistance and hyperinsulinemia increase the activity of the renin-angiotensin-aldosterone system and, by enhancing the expression of angiotensinogen, angiotensin II and its type 1 receptors, favors the development of AH, proinflammation, atherosclerosis, and congestive heart failure. Hyperleptinemia, which, by stimulating the activity of the sympathetic nervous system, elevates BP, plays a certain role in the development of AH in metabolic syndrome and obesity.

[The main pathophysiological mechanisms of kidney injury in obstructive sleep apnea syndrome].

Nowadays, obstructive sleep apnea syndrome (OSAS) has been established to promote both structural and functional changes in the kidneys. The basis for these changes is pathophysiological mechanisms, such as hyperproduction of free radicals and disruption of NO-mediated vasodilator responses, activation of the sympathetic autonomic nervous system and the renin-angiotensin-aldosterone system, endothelial dysfunction, development of renal venous hypertension, and stimulation of atrial natriuretic peptide production, which in turn results in increased intraglomerular pressure and glomerular hyperfiltration. In patients with OSAS, the kidneys may be damaged by OSAS-related abnormalities, such as hypertension, diabetes mellitus, metabolic syndrome, erythrocytosis, atherosclerosis, and cor pulmonale, which may also lead to kidney injury under isolated conditions and, when concurrent OSAS is present, may even aggravate the existing kidney injury.

[Microalbuminurea as an early indicator of renal lesion in arterial hypertension].

Arterial hypertension (AH) is undoubtedly associated with progressive renal dysfunction. Microalbminuria (MAU) is a reliable indicator of the early stage of renal disease and predictor of AH progress as well as an independent risk factor of cardiovascular mortality and death. The main pathophysiological mechanisms of MAU in AH are enhanced glomerular hydrostatic pressure, structural changes and endothelial dysfunction in glomerular capillaries. Also, an important role is played by AH-related progressive chronic preclinical inflammation as appears from positive correlation between MAU and CRP, fibrinogen, and cytokines. It is concluded that evaluation of MAU as an indicator of cardiovascular risk needs to be widely used in clinical practice for the improvement of AH treatment and the reduction of probability of complications.

[The history of study of respiratory disorders of sleep].

The pathologic breath during sleep was mentioned already by ancient historians. The respiratory disorders during sleep and particularly the syndrome of obstructive apnea in sleep were described in details already in early 1970s. Only 20 years later they became widely approved as a wide-spread and significant issue of public health. The considerable portion of society and even medical society has no enough knowledge of this problem. The article attempts to present in details historical aspects of its development.

[Indices of static and dynamic components of pressure load (assessed by 24-hour blood pressure monitoring) and the state of renal function in patients with essential hypertension].

Aim of this study was to evaluate possible relationship between parameters of blood pressure (BP) profile and glomerular filtration rate in patients (pts) with I-II stage essential hypertension (EH). Material and methods. We studied 120 pts (97 men), aged 23-65 (50,2+/-0,6) years with I (n=98) and II (n=22) stage EH. In BP profile (SL-90207) we calculated 24-hour, daytime, nighttime values of systolic, diastolic, pulse pressures (SBP, DBP, PP), time load (TL), variability and nocturnal fall (NF) of BP. The state of renal function was assessed by measurement of glomerular filtration rate (GFR) calculated by the Cockcroft formula. Results. After nonlinear statistical analysis by Gauss-Newton all patients were divided into three groups according to GFR tertiles. Significant differences were found between these groups by 24-hour, nighttime and daytime values of SBP and DBP. Values of SBP were the lowest in group II. In group II lowest values of PP were also observed, but statistically significant differences were found only in nocturnal PP values between groups II and III. There were no significant differences between groups by TL and NF of BP. In group Ill (high GFR) variability of daytime values of SBP and DBF were significantly higher. Univariate correlation analysis showed statistically significant negative relationship between GFR and nocturnal PP in patients with lowest level of GFR. Positive correlations between nocturnal values of PP and GFR in groups II and III were also observed. Conclusion. These results indicated the presence of strong relationship between high values of nocturnal PP and decreasing of glomerular filtration rate in patients with EH and thus confirmed significance of "constant" and "dynamic" components of pressure load as a marker of impairment of renal function.

[Characteristics of hypotensive effect in patients with arterial hypertension and desaturation signs of obstructive sleep apnea syndrome during sleep]. / Osobennosti gipotenzivnogo éffekta u bol'nykh arterial'noi gipertoniei s desaturatsionnymi priznakami sindroma obstruktivnogo apnoé vo vremia sna.

AIM: To estimate the efficacy of 8-week antihypertensive monotherapy in patients with arterial hypertension (AH) regarding the presence of obstructive sleep apnea syndrome (OSAS). MATERIAL AND METHODS: We analysed the results of 24-h blood pressure (BP) monitoring of 26 inpatients (mean age 54 +/- 2 years) with mild (n = 18) and moderate (n = 8) AH before and after 8 weeks of treatment with 5-10 mg amlodipine or 50-100 mg of losartan once daily to assess blood pressure profile parameters. The patients underwent nocturnal monitoring of arterial oxygen saturation (pulsoximeter NONIN-8500 M, USA). The presence of OSAS was confirmed when a characteristic clinical picture was combined with the presence of significant (> 4%) sleep desaturation episodes > 15 episodes per hour or the presence of group desaturation episodes below 90%. Seven hypertensive patients with OSAS were assigned to group 1, nineteen patients without OSAS--to group 2. The differences in estimated parameters between the groups were tested by Mann-Whitney U test, the dynamics of BP profile parameters--by Wilcoxon matched pairs test. RESULTS: In group 1 there were no significant differences by most of BP profile parameters before and after antihypertensive treatment, except mean nocturnal systolic BP. In group 2 a significant hypotensive effect was seen by all parameters of BP profile except BP variability. Hypotensive efficacy in group 2 was 1.5-2 times higher vs group 1, but the difficulties were not significant. CONCLUSION: Antihypertensive therapy in hypertensive patients with OSAS is less effective than in those without OSAS but it is not uneffective.

[24-hour blood pressure rhythm: clinical and predictive value]. / Sutochnyi ritm arterial'nogo davleniia: klinicheskoe znachenie i prognosticheskaia tsennost'

Clinical and predictive value of 24-hour blood pressure rhythm is reviewed. Insufficient nocturnal blood pressure lowering induces augmented pressure load on target organs. On the other hand it reflects dysregulatory changes due to target-organ involvement. Lack of adequate nocturnal blood pressure lowering is considered by some investigators as independent risk factor of target-organ damage. This dictates necessity of registration of parameters of 24-hour blood pressure profile in evaluation of patients with hypertension.

[Nocturnal hypoxic episodes and structural changes in left ventricular myocardium in patients with mild-to-moderate arterial hypertension]. / Nochnye gipoksicheskie épizody i strukturnye izmeneniia miokarda levogo zheludochka u bol'nykh miagkoi i umerennoi arterial'noi gipertoniei

AIM: To study correlations between structural changes of the left ventricle (LV) in patients with mild and moderate arterial hypertension (AH) and severity of hypoxic night episodes. MATERIAL AND METHODS: The examination of 50 patients (mean age 52 +/- 1 year) with mild and moderate hypertension included echocardiographic measurement of LV myocardial mass, calculation of LV myocardial mass index. LV hypertrophy was stated in the index 125 g/m2 for men and 110 g/m2 for women. 24-h monitoring of arterial pressure (TM-2425) and night monitoring of hemoglobin saturation of arterial blood with oxygen (SaO2) using pulsoxymeter NONIN 8500M were made. The data processing was performed with the use of original program ARM-SaO2. Dissaturation was stated if SaO2 fell by 4% and more compared to the previous stable level at initial SaO2 level above 90%. The patients were divided into two groups according to the number of dissaturation episodes: group 1 (more than 20 dissaturation episodes) and group 2 (less than 20 episodes). RESULTS: The groups were comparable by gender, duration of hypertension, body mass index, systolic and diastolic arterial pressure, heart rate. In group I, pulse arterial pressure, systolic arterial pressure load for 14 hours, day and night were significantly higher. Patients with dissaturation had a significantly higher LV myocardial mass and more frequent LV hypertrophy (128 +/- 6 and 106 +/- 5 g/m2 and 56 and 20%, respectively). The correlation and multifactor regression analysis showed a predictive value not only of the pressor parameters but also of indices of night hypoxia in relation to structural changes of LV myocardium. CONCLUSION: The presence of significant hypoxic episodes in sleep in AH patients indicates risk to develop structural changes of LV myocardium.

[Obstructive sleep apnea: clinical significance and correlations with arterial hypertension]. / Sindrom obsruktivnogo apnoé vo sne: klinicheskaia znachimost' i vzaimosviaz' s arterial'noi gipertoniei.

Obstructive sleep apnea (OSA) occurs rather frequently. It often combines with arterial hypertension (AH) and contributes to development and course of such severe conditions as stroke, myocardial infarction, arrhythmia, sudden death in sleep. Lack of adequate knowledge of relevant symptoms, cause-effect relationships leads to mistakes in management of patients. AH patients with OSA should receive combined treatment including hypotensive drugs and correctors of sleep respiratory disorders.

[Pulse blood pressure (according to 24-hour monitoring) and left ventricular myocardial structural changes in patients with hypertensive disease]. / Pul'sovoe arterial'noe davlenie (po dannym sutochnogo monitorirovaniia) i strukturnye izmeneniia miokarda levogo zheludochka u bol'nykh gipertonicheskoi bolezn'iu.

AIM: To study a relationship of the magnitude of structural changes in the left ventricle (LV) to the mean daily pulse blood pressure (PBP) in patients with hypertensive disease (HD). MATERIALS AND METHODS: 70 male patients (mean age 49 +/- 1 years) with stages I (n = 54) to 11 (n = 16) HD. LV mass (LVM) was estimated by echocardiography according to the formula derived by R. B. Devereux et al. and normalized to body surface area [the LVM index (LVMI)]. The relative thickness index (RTI) for the posterior wall (PWRTI) and ventricular septum (VSRTI) was calculated as a ratio of the sum of PWRTI and VSRTI to the LV end-diastolic size. LVMI > 125 g/m2 was considered to be a criterion for LV hypertrophy (LVH). 24-hour blood pressure (BP) monitoring was performed with a Spacelabs-90207 device (USA). According to the 24-hour PBP value, the patients were divided into 2 groups: 1) those (n = 17) having PBP24 > 53 mm HG and 2) those (n = 53) having PBP24 < 53 mm Hg. RESULTS: Group 1 patients were found to have significantly higher LVMI, LV WRTI, and incidence of LVH and a complex of changes in the BP profile as higher values of 24-hour systolic, diastolic and mean BP, PBP, and BP variations. Multiple regression analysis revealed a highly significant contribution of PBP24 to the development of LVH. CONCLUSION: The pedictive value of PBP as an index that characterizes a dynamic pressure load in regard to LV structural changes is higher than that of mean BP as a static load index and a BP variation index.

[24-Hour blood pressure profile in patients with mild and moderate arterial hypertension and sleep apnea/hypopnea]. / Osobennosti sutochnogo profilia arterial'nogo davleniia u bol'nykh miagkoi i umerennoi arterial'noi gipertoniei s sindromom apnoé/gipopnoé vo sne.

AIM: To evaluate 24-hour blood pressure (BP) profile in arterial hypertension (AH) patients (pts) with desaturation signs of sleep apnea/hypopnea syndrome (SAHS). MATERIAL AND METHODS: We investigated 61 pts (44 males and 17 females) aged between 23-70 (52 +/- 2) years with mild to moderate AH. BP monitoring was performed with multisensor system TM-2425 (A&D, Japan). We assessed the following parameters: mean 24-h, awake, sleep systolic (S), diastolic (D) and pulse (P) BPs, systolic and diastolic BP loads ("normalized area under the curve"--NAUC). A normal circadian rhythm of BP was defined when nocturnal fall of SBP was > 10% and < 20%. The morning rise of BP we assessed by speed of increase of mean BP from 4 a.m. to 12 a.m. The nocturnal monitoring of arterial oxygen saturation(SaO2) was performed with pulseoximeter "NONIN 8500M" (USA). The analysis of the results was performed with the original program ARM-SaO2". The presence of SAHS was confirmed when the number of 4% desaturations were greater than 15 per hour or in the presence of group episodes of 4% desaturation below 90%. In 19 pts we revealed desaturation signs of SAHS. The comparison group included pts without SAHS (n = 42). We compared the groups regarding 24-h BP profile parameters. RESULTS: SAHS group had the following parameters significantly higher: mean 24-h (151.7 +/- 4.5 vs 142.9 +/- 2.4 mm Hg, p < 0.07) and sleep SBPs (142.8 +/- 5.1 vs 132.7 +/- 2.6 mm Hg, p < 0.05); mean 24-h (65.2 +/- 2.6 vs 55.9 +/- 1.9 mm Hg, p < 0.008), daytime (65.6 +/- 2.7 vs 56.6 +/- 2.0 mm Hg, p < 0.01) and sleep PBPs (64.1 +/- 2.7 vs 53.1 +/- 1.9 mm Hg, p < 0.002); 24-h (20.1 +/- 3.8 vs 12.6 +/- 1.8 mm Hg, p < 0.05) and sleep NAUC of SBP (24.6 +/- 4.4 vs 15.3 +/- 2.2 mm Hg, p < 0.03). In the group with SAHS were significantly higher the frequency of abnormal circadian rhythm of SBP (84 vs 57%, p < 0.05) and the speed of morning rise of mean BP (23.3 +/- 5.9 vs 8.5 +/- 2.8 mm Hg/h, p < 0.01). CONCLUSION: Our results suggest that pts with desaturation signs of SAHS are characterized by unfavourable changes in 24-h BP profile parameters, first of all owning to sleep systolic and pulse blood pressures with alteration of circadian rhythm and high speed of morning rise of BP.

[Circadian rhythm of arterial pressure and state of target-organs in patients with mild and moderate hypertension]. / Sutochnyi ritm arterial'nogo davleniia i sostoianie organov-mishenei u bol'nykh s miagkoi i umerennoi formami gipertonicheskoi bolezni.

AIM: To assess the state of target-organs in males with mild and moderate forms of essential hypertension (EH) in normal and disturbed 24-h rhythm of arterial pressure (AP). MATERIAL AND METHODS: Target-organs were examined in 70 males aged 30-62 years (mean age 49 +/- 1 years) with mild (n = 54) or moderate (n = 16) EH. The following tests were performed: ophthalmoscopy, echo-CG with estimation of the left-ventricular myocardial mass index (LVMMI), duplex scanning of the carotid arteries (DS), AP monitoring, measurements of plasma creatinine, relative density of the urine, glomerular filtration rate, examination of the neurological status. Circadian rhythm of AP was evaluated by a night fall (NF) of systolic pressure (SP). Patients with inadequate NF of SP (< 10%) entered group 1, those with normal NF of SP (10% < NF SP < 20%) were allocated to group 2. RESULTS: Patients of group 1 had a significantly higher LVMMI, more frequent occurrence of left ventricular hypertrophy and carotid artery affection (local thickening "intima-media"). In group 1 there was also a complex of unfavourable changes in AP circadian profile, especially at night. CONCLUSION: Mild/moderate EH with insufficient NF of SP is associated with more pronounced and frequent changes in the target-organs (left-ventricular hypertrophy, "intima-media" thickeing). Insufficient NF of AP initiates higher pressor load on the target-organs, on the one side, and reflects defective regulation which affects target-organs, on the other. Both these factors contribute to damage of the target-organs.

[Morning rise of systolic blood pressure (by 24-hour ambulatory monitoring) and platelet aggregability in essential hypertension patients]. / Utrennii pod''em arterial'nogo davleniia (po dannym sutochnogo monitorirovaniia) i aggregatsiia trombotsitov u bol'nykh gipertonicheskoi bolezn'iu.

AIM: To investigate the relationship between platelet aggregability (PA) and parameters of blood pressure (BP) in patients with essential hypertension (EH). MATERIALS AND METHODS: We analyzed 24-h BP recordings (SL-90207, 15-min day and 30 min night time intervals) of 47 hospitalized males with mild to moderate EH (mean age 48 +/- 1 years) to assess the following parameters: mean 24-h, awake (Aw) and nighttime (N) systolic (S) and diastolic (D) BP. We assessed the morning rise (MR) of BP using the new index: a relative morning rise of systolic BP-RMRSBP--(max value of SBP from 6 am to 12 am/mean asleep SBP) x 100%. The kinetics of mean aggregate size (MAS) changes was studied with aggregation analyzer model (230LA Biola Ltd., Russia). The following parameters were used for estimation of platelet aggregability: a relative increase in MAS 2 min after beginning of sample stirring--for spontaneous aggregation (SPA) and the maximum increase in the light transmission for 0.5 microM ADP-induced aggregation (ADPI-PA). The patients were divided into two groups according to the median value of RMRSBP: group 1 (n = 25, RMRSBP < 121%) and group 2 (n = 22, RMRSBP > 121%). The differences in estimated parameters were tested by Student two tailed t-tests and presented by M +/- SE. P < 0.05 was considered statistically significant. RESULTS: No significant differences have been found between the groups by mean age, body mass index, duration of arterial hypertension, mean 24-h, awake DBP and SBP. Statistically significant differences have been found between groups by SPA, ADPI-PA, night SBP, night DBP, RMRSBP, RMRDBP. In group 2 there was a correlation between RMRSBP and SPA, but not in group 1. CONCLUSIONS: The morning rise of systolic BP is associated with an increase of ADP-induced and spontaneous platelet aggregability in the patients with mild to moderate essential hypertension and apparently that association is more pronounced at high values of morning BP (more than 20% from mean nocturnal values of SBP).