scholarly journals Stimulus-specific functional remodeling of the left ventricle in endurance and resistance-trained men

2020 ◽  
Vol 319 (3) ◽  
pp. H632-H641
Author(s):  
Tony G. Dawkins ◽  
Bryony A. Curry ◽  
Aimee L. Drane ◽  
Rachel N. Lord ◽  
Cory Richards ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Adaptive Response ◽  
Loading Conditions ◽  
Volume Loading ◽  
Functional Remodeling

Training-specific functional remodeling of the LV in response to different loading conditions has been recently suggested, but not experimentally tested in the same group of individuals. Our data provide novel evidence of a dichotomous, training-specific LV adaptive response to hemodynamic pressure or volume loading.

Cardiac dimensions during extracorporeal membrane oxygenation

2005 ◽  
Vol 15 (4) ◽  
pp. 373-378 ◽  
Author(s):  
Ronald B. Tanke ◽  
Otto Daniëls ◽  
Arno F. van Heijst ◽  
Henk van Lier ◽  
Cees Festen
Keyword(s):  
Left Ventricle ◽  
Extracorporeal Membrane Oxygenation ◽  
Left Ventricular ◽  
Loading Conditions ◽  
Volume Loading ◽  
Membrane Oxygenation ◽  
Arterial Duct ◽  
Before And After ◽  
Fractional Shortening

Our aim was to analyze left ventricular fractional shortening during extracorporeal membrane oxygenation under the influence of changing volume loading conditions induced by a ductal left-to-right shunt. In all patients, the fractional shortening was observed using echocardiography before, during, and after bypass, irrespective of the presence or absence of the ductal left-to-right shunt. During membrane oxygenation, there was a significant decrease in fractional shortening (p less than 0.001), with no difference before and after membrane oxygenation. A greater decrease in fractional shortening was observed in the group with a ductal left-to-right shunt when compared to patients lacking the ductal shunt (p less than 0.006). The diastolic diameter of the left ventricle also increased significantly during the membrane oxygenation in those patients with left-to-right ductal shunting. Moreover, the patients with left-to-right shunting showed a very severe decreased fractional shortening, lower than 10 per cent, with significantly greater frequency (p less than 0.05) during the course of membrane oxygenation. Conclusion: An important decrease in left ventricular fractional shortening is observed during veno-arterial extracorporeal membrane oxygenation. Left-to-right shunting during bypass, as seen in the patients with patency of the arterial duct, increases the loading conditions on the left ventricle, and produces a significant increase in left ventricular diastolic dimensions. Despite the effects of volume loading produced by the ductal shunt during bypass, the decrease in fractional shortening is significantly more pronounced for these patients. Therefore, during membrane oxygenation the volume loading produced by the ductal shunt is unable to prevent a decrease in left ventricular fractional shortening.

scholarly journals Features of structural and functional remodeling of the left ventricle in patients suffering from arterial hypertension with concomitant hypothyroidism

2019 ◽  
Vol 26 (5) ◽  
pp. 43-52
Author(s):  
V. I. Tseluyko ◽  
L. M. Yakovleva ◽  
D. A. Korchagina
Keyword(s):  
Body Mass Index ◽  
Left Ventricle ◽  
Arterial Hypertension ◽  
Diastolic Dysfunction ◽  
Body Mass ◽  
Mean Value ◽  
Left Ventricular ◽  
Control Group ◽  
Functional Remodeling ◽  
The Mean

The aim – to study the features of structural and functional remodeling of the left ventricle in patients suffering from arterial hypertension with concomitant hypothyroidism and to determine clinical and past medical history and laboratory factors associated with their development. Materials and methods. 50 patients suffering from hypertension with concomitant hypothyroidism were enrolled into the study. Depending on the level of thyroid stimulating hormone in the serum the examined patients were distributed into two groups of 25 patients with the compensated and 25 with decompensated course of hypothyroidism. The control group consisted of 30 patients with hypertension in which the pathology of the thyroid gland was excluded. The comparison of the main parameters of the echocardiography study of the myocardium has been performed depending on hypothyroidism compensation. Assessment of parameters of transmitral diastolic blood flow has been performed. A regression analysis has been conducted to detect the relation of clinical and past medical history factors and echocardiographic parameters with the development of diastolic dysfunction by E/A ratio. The values of central hemodynamics have been studied for evaluation of the contractile function of the myocardium. Results and discussion. According to the results of the echocardiography of both examined groups it has been found that the final systolic and stroke volume exceeded the parameters of the control group. The mean value of the left ventricle ejection fraction was statistically significantly lower than in the control group (p=0.004). The left ventricle myocardial mass in patients with hypothyroidism was statistically significantly greater than in the control group. It was proved that in patients, who were diagnosed with decompensated hypothyroidism, the mean value of the left atrium size to growth by the degree of 2.7 was statistically significantly higher than in the control group (p=0.01), whereas the average value of the ratio of the size of the left atrium to the surface area of the body had no statistically significant differences between the groups. It has been found that in both groups the proportion of patients with diastolic dysfunction in which the E/A ratio was less than 1.0 was higher than in the control group (р=0.01 and p=0.03, respectively). The independent factors of diastolic dysfunction of the left ventricle in patients with hypertension in the presence of hypothyroidism have been found. Conclusions. In the presence of decompensated hypothyroidism in patients with arterial hypertension, both with obesity and with normal body mass index, left ventricular mass indexes were significantly higher in comparison with a control group. Regardless of the compensation of the thyroid state in patients with arterial hypertension, the ejection fraction was significantly lower. According to regression analysis, independent factors for the development of diastolic dysfunction in patients with arterial hypertension and hypothyroidism with a body mass index ≥ 30 kg/m2 is the index of mass of the left ventricular myocardium, determined by the degree of 2.7, the level of total cholesterol to statistical significance – the level of office systolic blood pressure and the duration of hormone replacement therapy for hypothyroidism; with body mass index < 30 kg/m2 – age and left atrial index, determined by body surface area. For patients with arterial hypertension and reduced thyroid gland function, violation of the left ventricular myocardial relaxation is typical as evidenced by a higher proportion of patients with a decrease in E/A to less than 0.8 in these patients.

Molecular and functional remodeling of Ito by angiotensin II in the mouse left ventricle

2010 ◽  
Vol 48 (1) ◽  
pp. 140-151 ◽  
Author(s):  
Magdalini Tozakidou ◽  
Diane Goltz ◽  
Till Hagenström ◽  
Mareike K. Budack ◽  
Helga Vitzthum ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Left Ventricle ◽  
Functional Remodeling

Dynamic stiffness profiles in the left ventricle

1975 ◽  
Vol 39 (4) ◽  
pp. 665-671 ◽  
Author(s):  
A. Kennish ◽  
E. Yellin ◽  
R. W. Frater
Keyword(s):  
Left Ventricle ◽  
Flow Measurement ◽  
Diastolic Pressure ◽  
Dynamic Stiffness ◽  
Normal Heart ◽  
Dynamic Effects ◽  
Transmitral Flow ◽  
Volume Loading ◽  
Rate Dependent ◽  
Viscous Element

Diastolic pressure-volume (P-V) curves were calculated on a beat-to-beat basis in the open-chest, pentobarbital-anesthetized dog, using the technique of direct transmitral flow measurement previously described. P-V curves were constructed and the slope (dP/dV) was plotted vs. pressure and time. dP/dV was used as an index of stiffness in each heart and its instantaneous changes with time were followed throughout the diastolic period. The end-diastolic P-V relation based on points from successive cycles during volume loading was found to be exponential. In contrast, the instantaneous P-V relation during any one diastolic period was not exponential. That is, the dynamic dP/dV vs. pressure plot was nonlinear. In the normal heart, stiffness was characterized in early diastole by a negative dP/dV as the ventricle continued to relax, and then frequently decreased prior to a second stiffness rise with atrial augmentation. These findings can be explained by a model containing an element whose deformation is rate dependent, i.e., a parallel viscous element. Stiffness profiles in mitral stenosis where dynamic effects are minimized substantiate this conclusion.

Nonuniformity and volume loading independently influence isovolumic relaxation rates

1989 ◽  
Vol 257 (6) ◽  
pp. H1927-H1935 ◽  
Author(s):  
T. C. Gillebert ◽  
W. Y. Lew
Keyword(s):  
Anterior Wall ◽  
Left Ventricular ◽  
Lv Function ◽  
Loading Conditions ◽  
Relaxation Rates ◽  
Volume Loading ◽  
Two Factors ◽  
Lv Volume ◽  
Pressure Fall ◽  
Isovolumic Relaxation

We examined the influence of loading conditions and nonuniformity of left ventricular (LV) function on the rate of LV pressure fall in seven anesthetized dogs. Loading conditions were altered with vena cavae occlusions and/or intravenous infusions of dextran. Nonuniformity was produced by injecting 8-20 ng of isoproterenol into the mild left anterior descending coronary artery to produce an asynchronous and early onset of segment lengthening in the anterior wall. Temporal and regional nonuniformity were quantified with indexes derived by comparing segment lengths in the anterior and posterior walls, measured with midwall sonomicrometers. The rate of LV pressure fall was assessed with peak -dP/dt, the time constant, tau, and the duration of isovolumic relaxation. Volume loading decreased the rate of LV pressure fall without altering the nonuniformity indexes. Intracoronary isoproterenol produced nonuniformity and decreased the rate of LV pressure fall without altering global loading conditions. The effects of isoproterenol (in a constant dose) were similar irrespective of the LV volume. We conclude that in the intact, ejecting left ventricle, loading conditions and nonuniformity are important determinants of the rate of LV pressure fall, but these two factors exert their influence by mechanisms that are largely independent.

scholarly journals Diastolic function left ventricle in a debut of revealing of hypertonic illness at young age

2007 ◽  
Vol 13 (4) ◽  
pp. 292-294
Author(s):  
V. V. Kuznetsova ◽  
A. V. Bursikov
Keyword(s):  
Left Ventricle ◽  
Arterial Hypertension ◽  
Diastolic Function ◽  
Doppler Echocardiography ◽  
High Speed ◽  
Young Age ◽  
Left Auricle ◽  
Functional Remodeling ◽  
Peak Speed

The purpose: To estimate diastolic function left ventricle at persons of young age with recently revealed arterial hypertension and to reveal early attributes of its infringement. Materials and methods: On device LOGIQ 500 method Doppler echocardiography studies diastolic function left ventricle at 34 patients of young age with prescription of revealing arterial hypertension no more than 3 years and practically healthy 48 persons. Results: At an arterial hypertension already in a debut of revealing of disease change of some Doppler echocardiography parameters diastolic fillings left ventricle takes place: decrease in high-speed parameters early diastolic fillings and increase in peak speed and fraction of late filling left ventricle, that reflects difficulty of filling left ventricle and increased hemodinamic loading on the left auricle. The conclusion: Changes of speeds diastolic fillings left ventricle reflects its structurally functional remodeling and can be used as criterion of diagnostics of defeat of heart at arterial hypertension

Relation between oxygen consumption and pressure-volume area of in situ dog heart

1987 ◽  
Vol 253 (1) ◽  
pp. H31-H40 ◽  
Author(s):  
T. Nozawa ◽  
Y. Yasumura ◽  
S. Futaki ◽  
N. Tanaka ◽  
Y. Igarashi ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Left Ventricle ◽  
Systolic Pressure ◽  
Ascending Aorta ◽  
Aortic Occlusion ◽  
O2 Consumption ◽  
Loading Conditions ◽  
Contractile State ◽  
Dog Heart

We studied the relation between O2 consumption (VO2) and the systolic pressure-volume area (PVA) in the left ventricle of open-chest dogs. PVA and the slope (Emax) of the end-systolic pressure-volume line were determined by an abrupt occlusion of the ascending aorta. VO2 linearly correlated with PVA in control contractile state, where Emax was 15.8 +/- 4.4 (SD) mmHg/ml with intact reflexes and 11.5 +/- 1.2 mmHg/ml with blocked reflexes. Emax and the VO2 axis intercept of the VO2-PVA line were greater in the in situ heart than in the excised cross-circulated dog heart in our previous study. Enhancement of contractile state by dobutamine increased Emax by 60–80% and shifted the VO2-PVA line upward, increasing the VO2 axis intercept by 38% with intact reflexes and by 79% with blocked reflexes. The slope had a tendency to increase with dobutamine, but the increase was statistically insignificant. We conclude that PVA and Emax obtained by the aortic-occlusion method can account for changes in VO2 with changes in loading conditions and contractility in an in situ dog heart.

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