PubMed Health⌕ Search

Biomedical subjects

V V Chestukhin

Publications and source records attributed to V V Chestukhin.

At least 37 records · Page 2Linked to original sources
PubMed1987

Central and coronary circulation of the normal man during orthostatic and lower body negative pressure tests.

The effects of the tilt test (at 60-70 degrees for 20 min) and LBNP test (at -30 and -60 mm Hg for 20 min each) on the basic parameters of central circulation (15 test subjects) and coronary circulation (11 test subjects) were investigated. The study was performed using thermistor-equipped catheters implanted into the pulmonary artery and coronary sinus and Teflon catheters implanted into the brachial artery. In the study, the basic parameters of central circulation (pressure in the right atrium and pulmonary artery, transmural pressure in these compartments, cardiac index, stroke index, etc.) and coronary circulation (blood flow in the coronary sinus, left ventricle oxygen consumption, coronary resistance, etc.) were measured. Correlation between circulation variations and metabolic requirements was assessed (with respect to changes in acid-base equilibrium of blood). The effect of the tilt test and LBNP test on the basic parameters of central and coronary circulation, blood acid-base equilibrium and oxygenation was compared.

Acid-Base Equilibrium↗
PubMed1985

Coronary circulation of the healthy man exposed to tilt tests, LBNP, and head-down tilt.

The effect of tilt (head-up and head-down) tests, LBNP tests, and 7-d head-down tilt (at -15 degrees) on coronary circulation was investigated in healthy male volunteers. Catheters were implanted into the coronary sinus and brachial artery. The Ganz catheter in the coronary sinus was used to measure volume flow in the area (constant thermodilution), pressure, and to withdraw samples of outflowing blood for biochemical analysis (acid-base equilibrium and oxygenation). Transfer from supine to upright body position, lower body negative pressure (-30 mm Hg for 20 min), as well as 15 degrees head-down (by day 5-6) produced similar changes in the basic parameters of coronary circulation-reduction of blood flow and oxygen consumption, decrease of pressure in the coronary sinus, and increase of coronary resistance. Transfer from head-up to head-down position caused opposite changes of the above parameters. The changes in coronary circulation were adequate for myocardial metabolic requirements since the biochemical composition of the outflowing blood remained essentially constant during the gravitational exposures described.

Adult↗
PubMed1984

On the mechanism of accentuation of the first heart sound in mitral stenosis.

In 10 patients with mitral stenosis, catheterization of the left ventricle and the left atrium has revealed a considerable increase in dp/dt at the moment of closure of the mitral valve in comparison with 10 healthy controls. Systolic and diastolic pressure and the contractility indicators (dp/dtmax and dp/dtmax/P) did not differ from the values found in the controls, and Vmax was even reduced. Simultaneously with the change in the dp/dt ratio at the moment of the mitral valve closure there occurred also a proportional change in the Ist heart sound amplitude. The authors therefore suggest that besides anatomical changes, a role in the accentuation of the Ist heart sound in mitral stenosis is played also by the haemodynamic factor - the dp/dt ratio at the moment of the mitral valve closure.

Electroencephalography↗
PubMed1983

Central circulation of a normal man during 7-day head-down tilt and decompression of various body parts.

The effect of 7-d head-down tilt (-15 degrees) and decompression of various body parts (lower body--LBNP, upper body in the area of the hydrostatically indifferent point--UBNP, and local negative pressure applied to both calves--LNP) on central circulation was investigated on eight healthy test subjects who, for 10 d, had catheters (Swan-Ganz) implanted into the pulmonary and radial arteries. It was shown that, when calculated by square centimeter of the decompression area, the effect of UBNP on central venous pressure (CVP) and pulmonary artery pressure (PAP) was 3-4 times greater than that of LBNP or LNP. This indicates a high sensitivity of this body part to the exposure. During the 7-d study, CVP and PAP showed the most distinct changes. By the 7th hour of the head-down tilt study, CVP remained unchanged and systolic PAP increased by 5.5 mm Hg (27%) (p less than 0.05). This was paralleled by a decrease of plasma aldosterone and renin. By the 2nd day of the study, CVP and PAP were close to the pretest level; on the 3rd day, they began to decline and remained about 3 mm Hg lower than the pretest values to the end of the study (p less than 0.05). During this same period, the contractility of the right heart (the mean rate of right ventricular pressure increment) decreased by 34% (p less than 0.05) and its work by 27% (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1982

Effects of various countermeasures against the adverse effects of weightlessness on central circulation in the healthy man.

The effect of lower body negative pressure, local negative pressure below the knee joint, and both pneumatic and mechanical occlusion cuffs at the upper third of the femur on central circulation, oxidative metabolism, and acid-base equilibrium of blood was studied on eight healthy male volunteers with doublelumen Swan-Ganz flow-directed thermodilution catheters implanted for 7 d into the pulmonary artery. The counter-measures against the adverse effects of weightlessness were used in two regimens: regimen I at -30, -50, +40 torr and regimen II at -60, -100, and +60 torr. The parameters were recorded in recumbency, during the head up tilt at 70 degrees for 15 min, and then during the head-down tilt at -20 degrees for 60 min. After the first 20 min of anti-orthostasis, the effects of the above countermeasures in the two regimens were investigated. The tile-induced changes in central circulation, those observed during application of the countermeasures, and the effect of different countermeasures were studied on a comparative basis. It was demonstrated that the highly informative method of implantation of catheters into the pulmonary artery can be successfully used in biomedical investigations of normal men.

Acid-Base Equilibrium↗
PubMed1979

Short-term immobilization of healthy men: right ventricular function and metabolism during graded exercise.

Five healthy male volunteers were subjected to graded exercise tests on a bicycle ergometer (600 kpm/min for 8 minutes) with simultaneous catheterization of the right cardiac ventricle and radial artery, first before immobilization and them after five-day bed rest in the head-down posture (the foot bed end was elevated 4.5 degrees). After immobilization, during exercise the stroke index did not increase, the tachycardia was more marked, the indicators of right ventricular contractility increased [+ max dp/dt, mas (dp/dt) /P, --mas dp/dt], the arterial pressure decreased, and the lactic acid level in mixed venous blood rose. Possible causes of haemodynamic and metabolic alterations, occurring in healthy volunteers during graded exercise following short-term hypokinesis, are discussed.

Adult↗
PubMed1979

Central and cerebral hemodynamics and metabolism of the healthy man during head-down tilting.

Experiments on six healthy test volunteers, who underwent simultaneous catheterization of different cardiovascular compartments, were carried out to study the effect of head-down tilting at an angle of -20 degrees on the central and cerebral hemodynamics and metabolism. By the third hour of exposure, the test subjects showed a decrease in the systolic arterial pressure and increases in the systolic pressure of the right ventricle, heart rate, cardiac output, and oxygen intake. They also displayed a trend for an increase in the content of adenosine triphosphate, a decrease in the content of pyruvic acid, and essentially no changes in the concentration of lactic acid and activity of lactate dehydrogenase in the arterial blood and in the blood flowing out from the brain. The oxygen arteriovenous difference for the systemic and cerebral circulation decreased by 24% and 13%, respectively. The above circulatory and metabolic changes seem to reflect processes of adaptation of the human body to functioning under conditions of cephalad fluid shifts.

Acid-Base Equilibrium↗
PubMed1978

[Effect of short-term antiorthostatic hypokinesia on the central and intracardiac hemodynamics and metabolism in a healthy human being].

The right parts of the heart and the radial artery were catheterized in healthy male volunteers before and 5 days after strict bed rest in antiorthostatic position of the body (-4.5 degrees) After immobilization most values of central circulation showed no essential changes; the only exception were indices characterizing the inotropic myocardial condition. A shift in the direction of acidosis of a mixed character was noted in mixed venous blood, the beta-lipoprotein content increased. A decrease in the arteriovenous difference in oxygen was encountered in blood draining from the heart (from the coronary sinus).

Acid-Base Equilibrium↗
PubMed1976

[The relationship between the state of the pulmonary circulation and indices of cerebral gas exchange in patients with acquired heart defects].

The author studied the state of hemeostasis in normals and in patients with acquired heart insufficiency. By means of bloody methods of triple probe samples of the blood inflow and outflow from the brain, and by biochemical methods they also studied 22 normals and 100 patients with acquired heart insufficiency for interrelations between the gas metabolism indices and acid-base equilibrium of the central pulmonary hemodynamics. As a results it was established that the brain blood flux in patients with acquired heart insufficiency in different degrees of pulmonary hypertension is adequate to the metabolic requirement of the brain in oxygen and corresponds to identical indices in normals. There was no relation between the state of pulmonary circulation and brain circulation.

Acid-Base Equilibrium↗
PubMed1976

[Effect of hydrocortisone on some indices of cardiac activity and of the greater circulation in acquired heart defects].

The catheterization technique was used to study the effect of 100 mg of water soluble hydrocortisone "Russel" upon the cardiac activity and greater circulation in patients with acquired heart diseases. Hydrocortisone was found to produce different effects upon the cardiac output and tonicity of the greater circulation vessels--increases or decreases them, or does not change at all. The varying dynamics of these indices serves as a manifestation of the optimizing effect of hydrocortisone on the cardiovascular system, depends on the initial values of the parameters in question, and is directed towards normalizing the oxygen consumption in the body (its blood flow). No direct correlation was found between the cardiac output and the pressure in the ventricles in patients with acquired heart diseases prior to and following hydrocortisone administration.

Blood Circulation↗
PubMedDate not supplied

Evidence for antibody and immune-complex deposition in heart transplantation: a report of three cases.

Immunofluorescence microscopy of endomyocardial biopsy specimens from heart allograft recipients identified immunopathologic changes in three of 17 patients. These changes included immunoglobulin G and complement C3 deposition in tissue structures such as capillary endothelium and basal membranes, cardiomyocyte sarcolemma, and interstitial tissue. Moreover, the immunopathologic changes could be correlated with acute cellular rejection episodes evidenced by endomyocardial biopsy criteria.

Biopsy↗
PubMedDate not supplied

[Indices of human blood acid-base equilibrium and enzymatic activity in short-term antiorthostatic hypokinesia].

Before and after a 5 day head-down tilt of 4.5 degrees blood samples were withdrawn from different areas of the cardiovascular system of healthy male volunteers. Blood was sampled by means of selective catheterization. Parameters of acid-base equilibrium and activities of aminotransferases and alkaline phosphatase were measured. After immobilization the most significant changes were observed in the blood outflowing from the brain in which significant metabolic acidosis and increased activity of aspartate aminotransferase occurred. A slight increase in the activity of aspartate aminotransferase was also observed in the blood outflowing from the liver and kidneys. It is concluded that brain is the organ which is subjected to short-term simulated weightlessness in the highest degree.

Acid-Base Equilibrium↗
PubMedDate not supplied

[Effect of short-term antiorthostatic hypokinesia on carbohydrate metabolic indices and on the beta-lipoprotein content in human blood].

Before and after 5-day bed rest in the head-down position (at an angle of --4.5 degrees) the healthy male test subjects were exposed to selective catheterization with blood samples withdrawn drom different compartments of the cardiovascular system. The content of glucose insulin lactic acid and beta-lipoproteins was measured. After bed rest the systemic circulation--mixed arterial and venous blood--showed a trend for a decrease of carbohydrate metabolism and an increase of the content of beta-lipoproteins. Transcapillary metabolism in different organs, first of all, in the brain and liver altered significantly. The liver began to release glucose and ceased to utilize lactic acid whereas the brain increased substantially its release of beta-lipoproteins. The data obtained were analyzed using a model of carbohydrate metabolism to control and artifical pancreas.

Bed Rest↗