scholarly journals Effect of Angiotensin II on the Left Ventricular Function in a Near-Term Fetal Sheep with Metabolic Acidemia

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Ganesh Acharya ◽  
James C. Huhta ◽  
Mervi Haapsamo ◽  
Ole-Jakob How ◽  
Tiina Erkinaro ◽  
...  

We tested the hypothesis that, in acute metabolic acidemia, the fetal left ventricle (LV) has the capacity to increase its contractility in response to angiotensin II infusion. Eleven ewes and their fetuses were instrumented at 127–138/145 days of gestation. The effect of angiotensin II on fetal LV function was assessed using intraventricular pressure catheter and tissue Doppler imaging (TDI). Angiotensin II increased fetal arterial blood pressure, whereas pH and pO2decreased. The heart rate and systemic venous pressure were not affected significantly. The LV end-diastolic and end-systolic pressures, as well asdP/dtmax, increased. The TDI-derived LV longitudinal myocardial isovolumic contraction velocity and its acceleration and velocity during early filling were higher than those at baseline. The incidence of absent isovolumic relaxation velocity was greater during angiotensin II infusion. In summary, during acute metabolic acidemia, the fetal left ventricle could increase its contractility in response to inotropic stimulus even in the presence of increased afterload. The diastolic LV function parameters were altered by angiotensin II.

Author(s):  
Johan De Sutter ◽  
Jean-Louis J. Vanoverschelde

The evaluation of diastolic function in patients with reduced (HFREF) or preserved (HFPEF) left ventricular (LV) ejection fraction is important as it carries both diagnostic and prognostic information. In daily practice, this is most frequently done by standard echocardiographic techniques, including the evaluation of LV mass and LA volumes, as well as transmitral and pulmonary venous PW Doppler, CW Doppler for evaluation of the IVRT, and tissue Doppler imaging of the septal and lateral annular velocities. This permits grading the severity of diastolic dysfunction, which is related to outcome and may be used to estimate LV filling pressures. The latter needs further validation, especially in patients with HFPEF. Newer echocardiographic and cardiac magnetic resonance techniques, including myocardial deformation measurements during diastole, LV twist and untwisting, and parameters of left atrial function, are promising and will hopefully in the future help clinicians to make a more precise evaluation of diastolic function and filling pressures in heart failure patients.


2006 ◽  
Vol 291 (4) ◽  
pp. H1773-H1779 ◽  
Author(s):  
Damien Logeart ◽  
Laurent Vinet ◽  
Thierry Ragot ◽  
Michèle Heimburger ◽  
Liliane Louedec ◽  
...  

The aim of this study was to examine the efficiency of adenovirus-mediated overexpression of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA1a) gene in a realistic model based on percutaneous intracoronary delivery and on noninvasive functional monitoring. Catheter-based selective coronary delivery of saline or adenoviruses (Ad.CMV.SERCA1a or Ad.CMV.lacZ, 1010 plaque-forming units) was performed in the circumflex artery of rabbits. Effects were assessed and compared by using serial Doppler echocardiography, hemodynamics, and measurements of SERCA protein and Ca2+ uptake activity. On day 3, a 21% increase in SERCA proteins and a 37% increase in the maximal rate of Ca2+ uptake were observed in the transfected left ventricular (LV) walls of Ad.CMV.SERCA1a rabbits. Baseline hemodynamics and conventional echographic measurements of global LV function were poorly affected. In contrast, tissue Doppler imaging (TDI) was able to assess a strong increase in the baseline function of transfected LV walls, as assessed with maximal wall velocities (+32% and +43%, respectively) and strain rates (+18% and +30%, respectively). TDI parameters were closely related to the maximal rate of Ca2+ uptake ( r2 = 0.68 for the systolic strain rate). Serial TDI analysis during follow-up showed that the effects lasted for 7 days and were no longer detectable 15 days after adenoviruses injection. In conclusion, LV function can be increased by adenovirus-mediated overexpression of SERCA in a clinically relevant model, and TDI provides an accurate and noninvasive tool for monitoring effects on global as well as regional myocardial function.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Lisulov Popovic Danica ◽  
Mirjana Krotin ◽  
Marija Zdravkovic ◽  
Ivan Soldatovic ◽  
Darko Zdravkovic ◽  
...  

The aim of the study was to evaluate whether obstructive sleep apnea (OSA) contributes directly to left ventricular (LV) diastolic and regional systolic dysfunction in newly diagnosed OSA with normal left ventricle ejection fraction.Methods. 125 consecutive patients were prospectively enrolled in the study. Control group consisted of 78 asymptomatic age-matched healthy subjects who did not have any cardiovascular and respiratory diseases. All patients had undergone overnight polysomnography and standard transthoracic and tissue Doppler imaging echocardiogram.Results. TheE/Aratio and the peakEwave at mitral flow were significantly lower and the peakAwave at mitral flow was significantly higher in OSA patients compared with control subjects. Left ventricle isovolumetric relaxation time (IVRT) and mitral valve flow propagation (MVFP) were significantly longer in OSA patients than in controls. Tissue Doppler derivedS′amplitude of lateral part at mitral valve (S′Lm) andE′wave amplitudes both at the lateral (E′Lm) and septal parts of the mitral valve (E′Sm) were significantly lower in OSA patients compared to controls.Conclusion. Newly diagnosed OSA patients with normal global LV function have significantly impaired diastolic function and regional longitudinal systolic function. OSA is independently associated with these changes in LV function.


2005 ◽  
Vol 289 (4) ◽  
pp. H1391-H1398 ◽  
Author(s):  
Sandrine Huez ◽  
Kathleen Retailleau ◽  
Philippe Unger ◽  
Adriana Pavelescu ◽  
Jean-Luc Vachiéry ◽  
...  

Hypoxia has been reported to alter left ventricular (LV) diastolic function, but associated changes in right ventricular (RV) systolic and diastolic function remain incompletely documented. We used echocardiography and tissue Doppler imaging to investigate the effects on RV and LV function of 90 min of hypoxic breathing (fraction of inspired O2 of 0.12) compared with those of dobutamine to reproduce the same heart rate effects without change in pulmonary vascular tone in 25 healthy volunteers. Hypoxia and dobutamine increased cardiac output and tricuspid regurgitation velocity. Hypoxia and dobutamine increased LV ejection fraction, isovolumic contraction wave velocity (ICV), acceleration (ICA), and systolic ejection wave velocity (S) at the mitral annulus, indicating increased LV systolic function. Dobutamine had similar effects on RV indexes of systolic function. Hypoxia did not change RV area shortening fraction, tricuspid annular plane systolic excursion, ICV, ICA, and S at the tricuspid annulus. Regional longitudinal wall motion analysis revealed that S, systolic strain, and strain rate were not affected by hypoxia and increased by dobutamine on the RV free wall and interventricular septum but increased by both dobutamine and hypoxia on the LV lateral wall. Hypoxia increased the isovolumic relaxation time related to RR interval (IRT/RR) at both annuli, delayed the onset of the E wave at the tricuspid annulus, and decreased the mitral and tricuspid inflow and annuli E/A ratio. We conclude that hypoxia in normal subjects is associated with altered diastolic function of both ventricles, improved LV systolic function, and preserved RV systolic function.


1982 ◽  
Vol 243 (6) ◽  
pp. H974-H981
Author(s):  
S. F. Flaim

The effects of intravenous nitroglycerin (NG; 2, 8, 32 micrograms/kg) on cardiocirculatory dynamics were evaluated in control normal (C) and chronically volume-overloaded [high-output heart failure (aortocaval fistula), HCO] conscious rats. Pressures were recorded in the left ventricle, the caudal artery, and the right atrium. Regional blood flows were determined by radioactive microsphere injection into the left ventricle with reference sampling from the caudal artery. Cardiac output (CO) was 289 ml . min-1 . kg in C and did not change with NG; however, in HCO systemic CO was decreased 31, 23, and 23% by NG from 350 ml . min-1 . kg. In both groups left ventricular end-diastolic pressure was reduced (C, 8.4–5.0; HCO, 19.8–12.7 mmHg); however, central venous pressure was reduced only in C (1.2–0.3 mmHg). During NG primarily at 2 and 8 micrograms/kg, arterial blood flow was lower and vascular resistance was higher in HCO compared with C in the following regions: kidney, ileum, jejunum, skin, heart, spleen, stomach, and testes, whereas no major differences were noted in the cerebellum, cerebrum, liver, or skeletal muscle. Thus acute NG infusion is a more potent regional vasodilator in C than in HCO. It is suggested that this difference is related to a more powerful NG-induced sympathetic reflex activation in the HCO group, which strongly attenuates the direct vasodilator effect of NG that was apparent in C.


Kardiologiia ◽  
2020 ◽  
Vol 60 (2) ◽  
pp. 33-40
Author(s):  
D. A. Shveс ◽  
S. V. Povetkin

Objective. The aim of the research under consideration was to study the dynamics of a local systolic-diastolic function of patients with various ischemic heart disease (IHD) progressions after survival of an acute coronary syndrome (ACS) provided there are residual stenoses of coronary arteries.Materials and Methods. There were 112 patients suffering from ACS who took part in the research. The diagnosis was verified (acute myocardial infarction or unstable angina) in accordance with the recommendations of European Society of Cardiology (ESC). All patients were divided into two groups depending on the occurrence of major acute cardiac events (MACE): 59 patients with aggravated IHD progression and 152 patients with non-aggravated course. Echo-cardiography was performed on a scanner Philips iE33 (the Netherlands) with a consideration to systolic and diastolic functions parameters of a left ventricle. Quantitative analysis of the left ventricle was executed in the mode of Tissue Doppler Imaging (TDI) and according to the method of tracing the patches of the ultra-sound image gray scale (ST).Results. In the course of the aggravated IHD a decrease in systolic-diastolic function of left ventricle has been discovered. It has been found out that the amount of the systolic peak of longitudinal strain of the left ventricle anteroseptal wall less than 12% is associated with a greater extent of coronary atherosclerosis and aggravated progression of IHD. TDI and ST methods have enabled to reveal that in the course of non-aggravated IHD the contractility and the diastolic function of the left ventricle anteroseptal wall improve in combination with the increase in the contractility of the left ventricle inferolateral wall. During an aggravated IHD progression the contractility and diastolic function of the left ventricle anteresoptal wall decreases without an increase in contractility and diastolic function of the inferior and inferolateral walls of the left ventricle. The reason for such results might be a progressing myocardial ischemia of the left ventricle anteroseptal wall despite the sufficient anterior interventricular artery stenting. The presence of the relevant residual stenoses of the circumflex and right coronary arteries increases the possibility of the aggravated IHD progressing especially by the end of the fourth year of observation.Conclusion. The disbalance of the local contractility of anterior, inferior and inferolateral left ventricle walls in the course of aggravated IHD is connected with the CA residual stenoses presence and forwards the decrease in global systolic-diastolic function of the left ventricle. The final results can serve as a foundation for optimization of recommendations for performing PCI on the patients with multivessel disease of CA.


Author(s):  
Alexandra Gonçalves ◽  
Pedro Marcos-Alberca ◽  
Peter Sogaard ◽  
José Luis Zamorano

This chapter describes the different modalities for assessment of systolic function by transthoracic echocardiography. Firstly, the basic principles of physiology and the determinants of left ventricular (LV) performance are considered, followed by a systematic appraisal of the methodologies for global LV systolic function assessment. Starting with M-mode echocardiography, passing through the traditional two-dimensional echocardiography evaluation to three-dimensional echocardiography approaches, main strengths and limitations are described. Power Doppler usefulness, regarding stroke volume calculations and dP/dt measurement are summarily explained, taking into consideration the usual pitfalls found in daily practice. There is a section dedicated to regional systolic function evaluation, with the recommendations for standardized LV division and differential characteristics of wall motion abnormalities. Additionally, more recent approaches with tissue Doppler imaging and strain analyses for global and regional LV function assessment are described. Finally, a section is dedicated to right ventricle systolic function which describes all modalities of evaluation.


2021 ◽  
Vol 10 (10) ◽  
pp. 2211
Author(s):  
Eunice Torres ◽  
Philip T. Levy ◽  
Afif El-Khuffash ◽  
Hongjie Gu ◽  
Aaron Hamvas ◽  
...  

Bronchopulmonary dysplasia (BPD) is characterized by alveolar-capillary simplification and is associated with pulmonary hypertension (PH) in preterm infants. The contribution of left ventricle (LV) disease towards this severe BPD-PH phenotype is not well established. We aimed to describe the longitudinal trajectory of the LV function as measured by tissue Doppler imaging (TDI) and its association with BPD-PH. We retrospectively assessed prospectively acquired clinical and echocardiographic data from 77 preterm infants born between 2011 and 2013. We characterized the LV function by measuring systolic and diastolic myocardial velocities (s’, e’, a’), isovolumetric relaxation time (IVRT), and myocardial performance index with TDI at three time periods from 32 and 36 weeks, postmenstrual age through one year of age. We also measured post systolic motion (PSM), a marker of myocardial dysfunction that results from asynchronous movement of the ventricular walls, and not previously described in preterm infants. Patients were stratified into groups according to BPD severity and the presence of PH and compared over time. Conventional TDI measures of the LV function were similar between groups, but the septal PSM was significantly prolonged over the first year of age in patients with BPD-PH. PSM provides a novel objective way to assess the hemodynamic impact of lung and pulmonary vascular disease severity on LV function in preterm infants with BPD and PH.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
C Fauvel ◽  
O Raitiere ◽  
N Si-Belkacem ◽  
C Viacroze ◽  
E Artaud-Macari ◽  
...  

Abstract Background While pulmonary vasodilation therapy improves right ventricular (RV) function in pulmonary arterial hypertension (PAH), data regarding left ventricular (LV) function remain sparse. Purpose We aimed to investigate whether PAH therapy improve LV function in PAH patients. Methods Between 2002 and 2020, all incident PAH patients from one PH referral centers were included, treated and followed-up according to current ESC/ERS guidelines. All patients had comprehensive echocardiography both investigating right and left ventricular function before and after 1-year of vasodilation therapy. In addition to RV echocardiographic evaluation, we focused on LV ejection fraction from Modified Simpson method, LV diameters by M-mode, transmitral pulsed-wave E/A ratio, Flow to tissue Doppler imaging E/e' ratio, and left atrial size. Results 126 patients were included (63% female, 57±17 yo), mainly from connectivite tissue associated and idiopathic PAH (24% and 28% respectively) causes. Compared to baseline, 1-year NYHA functional class (p<0.01), NTproBNP plasma level (p<0.001), invasive mean pulmonary arterial pressure (p<0.01) and cardiac index (p<0.01) significantly improved. While LV ejection fraction (p=0.68), LV end-diastolic diameter (p=0.11) as well as LA area and volume (p=0.09) were not significantly enhanced under vasodilation therapy, LV diastolic function, assessed by mitral E wave (p<0.01), tissue doppler imaging mitral e' wave (p=0.04), and E/A ratio (p=0.045) were significantly improved at 1-year. There was a significant correlation between LV end-diastolic diameter (p<0.001) and RV end-diastolic area (p<0.001) owing to the normalization of right- to left ventricular interdependence, as well as between mitral E wave and TAPSE (p=0.045). Conclusion By improving RV function, PAH vasodilation therapy enhances LV size and diastolic function and normalizes the biventricular interdependence. FUNDunding Acknowledgement Type of funding sources: None.


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