Interventricular Interaction Research Articles

Influence of pericardium on ventricular mechanical interdependence in an isolated biventricular working pig heart model.

The pericardium plays an important role in mechanical interactions between the right (RV) and left (LV) ventricles, referred to as ventricular interdependence. However, the exact mechanisms of its supportive role remain unknown. The present study aimed to evaluate specifically ventricular interdependence in a model of isolated biventricular working heart of large mammal, which is in absence of neurohormonal influence or series interactions, and to evaluate the impacts of intact pericardium on this phenomenon. Pig hearts were excised with the pericardium intact and connected to a biventricular working mode setup. Low and high ventricular preloads and afterloads were imposed on the hearts by changing independently the left (LA) and right (RA) atrial pressures, or the aortic (Ao) and pulmonary artery (PA) pressures, respectively, in the presence or absence of an intact pericardium. In the presence of the pericardium, increasing atrial pressures mainly impacted the ipsilateral ventricular haemodynamics, including an increase in ventricular outflow and end-diastolic pressures, independent of the contralateral atrial pressure. LV haemodynamics were also mainly altered by the increase in the ipsilateral afterload (Ao pressure). By contrast, RV haemodynamics, including the PA flow, were not only affected by increasing its ipsilateral (PA pressure), but also by its contralateral (Ao pressure) ventricular afterload. The preload but not afterload-dependent effects were abolished after removing the pericardium. Our work indicates that RV haemodynamics are highly impacted by the pericardiectomy. This highlights the requirement of keeping the pericardium intact to explore accurately cardiac haemodynamics, particularly in the RV. KEY POINTS: Pericardium has an important role in maintaining mechanical interventricular interaction, even if it is not essential for life. We used an ex vivo biventricular working pig heart model to explore intrinsic ventricular responses to independent variations of left and right preload and afterload, in the presence and absence of the pericardium. We show that, in the presence of the pericardium, the right ventricular haemodynamics is impacted by the ipsilateral preload as well as the ipsi- and contralateral afterloads, whereas the left ventricular haemodynamics is only impacted by its ipsilateral pre- and afterload. The preload but not afterload-dependent effects are abolished after removing the pericardium. These results demonstrate a critical function of the pericardium in maintaining RV haemodynamics, as well as preload-dependent ventricular interactions.

Biventricular interaction and aortic function in adult patients with repaired tetralogy of Fallot: a two-dimensional-three-dimensional speckle-tracking echocardiographic study.

In patients late after correction of tetralogy of Fallot (TOF), the combined effects of pre-operative hypertrophy and hypoxia, ventricular interdependence, acquired post-operative lesions such as pulmonary or aortic regurgitation, and congenital vasculopathy may result in impaired right ventricular (RV) and left ventricular (LV) function. The aim of the present study was to investigate the interventricular interactions in repaired TOF (rTOF) and the impact of aortic function on biventricular performance using two-dimensional (2D-STE) and three-dimensional speckle-tracking echocardiography (3D-STE). Twenty-five adult patients with rTOF and 25 age- and gender-matched healthy controls were studied. LV and RV volumes were determined by 3D-STE and cardiac magnetic resonance. LV and RV longitudinal strains (LVLS and RVLS) and LV and RV area strains (LVAS and RVAS) and LV twist/rotation were calculated by 3D-STE. Ascending aorta circumferential strain (AAo-CS) was obtained using 2D-STE. LV 3D-STE parameters were decreased in rTOF patients compared with controls even in patients with normal ejection fraction. AAo-CS was decreased (6.7 ± 1.9 vs. 10.1 ± 2.6, P = 0.003) in rTOF patients compared with controls even in the presence of normal aortic dimensions and correlated with AAo diameter (r = -0.69, P = 0.0001), LV twist (r = 0.54, P = 0.004), LVAS (r = -0.56, P = 0.003), and RVLS (r = -0.39, P = 0.036). LVAS and AAo-CS were associated with disease severity (peak oxygen consumption and arrhythmia occurrence). Significant improvement in global χ 2 value was noted with RV 3D-STE parameters + LVAS + AAo-CS compared with RV dysfunction alone for detecting exercise capacity impairment (from 77.1 to 84.4 to 91.2, P = 0.003). Speckle-tracking echocardiography revealed subtle LV and AAo dysfunction in adults with rTOF. A correlation was observed between LV and RV strain changes and between AAo strain impairment and LV/RV dysfunction. LV and AAo changes had an incremental value in evaluating disease severity.

Impact of Interventricular Interaction on Ventricular Function: Insights From Right Ventricular Pressure-Volume Analysis

BackgroundInterventricular interactions may be responsible for the decline in ventricular performance observed in various disease states that primarily affect the contralateral ventricle. ObjectivesThis study sought to quantify the impact of such interactions on right ventricular (RV) size and function using clinically stable individuals with left ventricular assist devices (LVADs) as a model for assessing RV hemodynamics while LV loading conditions were acutely manipulated by changing device speed during hemodynamic optimization studies (ie, ramp tests). MethodsThe investigators recorded RV pressure-volume loops with a conductance catheter at various speeds during ramp tests in 20 clinically stable HeartMate3 recipients. ResultsWith faster LVAD speeds and greater LV unloading, indexed RV end-diastolic volume increased (72.28 ± 15.07 mL at low speed vs 75.95 ± 16.90 at high speed; P = 0.04) whereas indexed end-systolic volumes remained neutral. This resulted in larger RV stroke volumes and shallower end-diastolic pressure-volume relationships. Concurrently, RV end-systolic pressure decreased (31.58 ± 9.75 mL at low speed vs 29.58 ± 9.41 mL at high speed; P = 0.02), but contractility, as measured by end-systolic elastance, did not change significantly. The reduction in RV end-systolic pressure was associated with a reduction in effective arterial elastance from 0.65 ± 0.43 mm Hg/mL at low speed to 0.54 ± 0.33 mm Hg/mL at high speed (P = 0.02). ConclusionsInterventricular interactions resulted in improved RV compliance, diminished afterload, and did not reduce RV contractility. These data challenge the prevailing view that interventricular interactions compromise RV function, which has important implications for the understanding of RV-LV interactions in various disease states, including post-LVAD RV dysfunction.

Abstract 12854: Early and Late Features of Intracardiac Flow in Repaired Tetralogy of Fallot (rTOF) Patients Using Doppler Velocity Reconstruction (DoVeR)

Background: Intracardiac flow analysis has implicated flow energy loss (FEL), kinetic energy (KE) and vortex strength (VS) as markers of ventricular dysfunction in repaired Tetralogy of Fallot (TOF); no studies have investigated early vs. late intracardiac flow conditions after repair. We utilized novel echocardiography (echo) based Doppler Velocity Reconstruction (DoVeR) to determine FEL, KE and VS in pre-operative TOF vs early post-repair (<1 month) and late post-repair (>10 years). Methods: This was a single-center retrospective cross-sectional study on TOF patients with pre- and post-operative surveillance transthoracic echo. Apical 4 chamber color Doppler views were collected. The streamfunction-vorticity formulation was used to reconstruct left ventricular (LV) blood velocity fields by DoVeR. Velocity flow fields were evaluated for peak FEL, KE and VS. The FEL was also normalized against KE to account for physiologic variations. Data were compared via one-way ANOVA. Results: Echo studies from 14 pre-operative (1.7±0.5 months), 14 early-post repair (3.6±2.3 months) and 15 late-post repair (16.5±6.6 years) TOF patients were included. There was significant variation in FEL, KE, VS, and normalized FEL across timepoints (all p<0.05) (Figure B). In general, when compared to pre-operative TOF, the early post-repair cohort had lower FEL/KE/VS corresponding to reduction in ventricular volume load; however late post-repair cohort had higher FEL/KE/VS, suggestive of effects from long-term interventricular interactions. Conclusion: The LV intracardiac flow in TOF changes early after initial repair and late after repair. DoVeR could potentially be used to serially evaluate TOF patients.

An in silico study of the effects of left ventricular assist device on right ventricular function and inter-ventricular interaction.

Left ventricular assist device (LVAD) is associated with a high incidence of right ventricular (RV) failure, which is hypothesized to be caused by the occurring inter-ventricular interactions when the LV is unloaded. Factors contributing to these interactions are unknown. We used computer modeling to investigate the impact of the HeartMate 3 LVAD on RV functions. The model was first calibrated against pressure-volume (PV) loops associated with a heart failure (HF) patient and validated against measurements of inter-ventricular interactions in animal experiments. The model was then applied to investigate the effects of LVAD on (1) RV chamber contractility indexed by derived from its end-systolic PV relationship, and (2) RV diastolic function indexed by derived from its end-diastolic PV relationship. We also investigated how septal wall thickness and regional contractility affect the impact of LVAD on RV function. The impact of LVAD on RV chamber contractility is small at a pump speed lower than 4k rpm. At a higher pump speed between 4k and 9k rpm, however, RV chamber contractility is reduced (by ~3% at 6k rpm and ~10% at 9k rpm). The reduction of RV chamber contractility is greater with a thinner septal wall or with a lower myocardial contractility at the LV free wall, septum, or RV free wall. RV chamber contractility is reduced at a pump speed higher than 4k rpm, and this reduction is greater with a thinner septal wall or lower regional myocardial contractility. Findings here may have clinical implications in identifying LVAD patients who may suffer from RV failure.

(841) Interventricular Interactions in LVAD Recipients: Insights from PV Loop Analysis

(841) Interventricular Interactions in LVAD Recipients: Insights from PV Loop Analysis

Impact of T2DM on right ventricular systolic dysfunction and interventricular interactions in patients with essential hypertension: evaluation using CMR tissue tracking

BackgroundPrevious studies reported that there was right ventricular (RV) systolic dysfunction in patients with hypertension. The aim of this study was to evaluate the impact of type 2 diabetes mellitus (T2DM) on RV systolic dysfunction and interventricular interactions using cardiac magnetic resonance feature tracking (CMR-FT) in patients with essential hypertension.Methods and methodsEighty-five hypertensive patients without T2DM [HTN(T2DM −)], 58 patients with T2DM [HTN(T2DM +)] and 49 normal controls were included in this study. The biventricular global radial, circumferential and longitudinal peak strains (GRS, GCS, GLS, respectively) and RV regional strains at the basal-, mid- and apical-cavity, were calculated with CMR-FT and compared among controls and different patient groups. Backward stepwise multivariable linear regression analyses were used to determine the effects of T2DM and left ventricular (LV) strains on RV strains.ResultsThe biventricular GLS and RV apical longitudinal strain deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM +) groups. RV middle longitudinal strain in patient groups were significantly reduced, and LV GRS and GCS and RV basal longitudinal strain were decreased in HTN(T2DM +) but preserved in HTN(T2DM-) group. Multivariable regression analyses adjusted for covariates demonstrated that T2DM was independently associated with LV strains (LV GRS: β = − 4.278, p = 0.004, model R2 = 0.285; GCS: β = 1.498, p = 0.006, model R2 = 0.363; GLS: β = 1.133, p = 0.007, model R2 = 0.372) and RV GLS (β = 1.454, p = 0.003, model R2 = 0.142) in hypertension. When T2DM and LV GLS were included in the multiple regression analysis, both T2DM and LV GLS (β = 0.977 and 0.362, p = 0.039 and < 0.001, model R2 = 0.224) were independently associated with RV GLS.ConclusionsT2DM exacerbates RV systolic dysfunction in patients with hypertension, which may be associated with superimposed LV dysfunction by coexisting T2DM and suggests adverse interventricular interactions.

Interventricular Interactions and Right Ventricular Function in LVAD Recipients: Insights from Pressure Volume Analyses

<h3>Purpose</h3> Data supporting the hypothesis that interventricular interaction contribute to right ventricular (RV) failure after left ventricular assist device (LVAD) implantation are lacking. <h3>Methods</h3> Patients underwent a protocolized hemodynamic ramp test where RV pressure-volume (PV) loops were recorded with a conductance catheter. The end-systolic PV relationship was characterized by the ratio of end-systolic pressure and volume (R_es). The end-diastolic PV relationship (EDPVR) was characterized by the V₁₀ index (i.e., the volume at which the EDPVR reaches a pressure of 10 mmHg). ΔR_es and ΔV₁₀ (i.e., the maximal change across the range of tested LVAD speeds) were used to compare systolic and diastolic function between patients. <h3>Results</h3> Six adult males with HeartMate3 LVADs completed the study protocol (Fig. 1). ΔR_es and ΔV₁₀ both exhibited minimal changes in 3 subjects (mean ΔR_es=7.24%, mean ΔV₁₀=8.14 mL), suggesting neither RV systolic nor diastolic function was impacted by LV unloading. In contrast, 2 subjects showed predominantly diastolic responses to changing LVAD speed (mean ΔV₁₀=17.4), but no significant systolic response (mean ΔR_es=5.47%). The final subject's ramp study was stopped prematurely because of suction events: ΔR_es and ΔV₁₀ were 23.2% and 1.4 mL, respectively, indicating a significant decrement in systolic function with greater LVAD speed. The mean PA systolic pressures were significantly greater in the 3 participants without systolic or diastolic changes relative to their counterparts (42.3 vs. 25.3 mmHg, p=0.038). <h3>Conclusion</h3> Interventricular interaction exerts a heterogenous influence on RV performance: Systolic interactions diminish RV contractile function, while diastolic interactions improve RV compliance. Further work is required to establish whether interventricular interaction is, indeed, a rare cause of post-LVAD RV dysfunction, and if chronic exposure to afterload blunts the RV's sensitivity to interventricular interaction.

Significance of echocardiographic right ventricular predictors of adverse prognosis in right ventricular dysfunction in patients with HFrEF

Abstract Funding Acknowledgements Type of funding sources: None. Background Dysfunction of the RV in patients with HFrEF is a prognostically unfavorable factor, which depends on the etiology, the duration of myocardial damage and the tactics of the treatment (Pharmacotherapy, Heart Surgery, CRTD, Heart Transplantation). RV function in patients with HFrEF realized in the concept of continuous contraction of the muscle tape proposed by Torrent-Guasp, where systolic and diastolic interventricular interactions are carried out through the common IVS and implemented in the degree of dyssynchrony of ventricular contraction. 3DERV and STE (GLSRV, FWLS) may add the prognostic value of the more commonly used RV functional parameters as the sensitive echocardiographic predictors of worse prognosis in patients with HFrEF. Methods and Results A total of 79 patients with HFrEF (age, from 26 to 77 years; the clinical manifestations of HFrEF corresponded to NYHA III in 52 patients (71%), NYHA IV in 27 patients (29%); LV EF ≤ 35%). The etiology of HFrEF was mainly connected to patients with ischemic heart disease- 50 (63.2%), non-ischemic genesis 29 (36, 7%).The primary endpoint was a death in the follow-up period of up to 3 years in 33 patients (45,2%). An adverse outcomes and mortality during the first year was 17 (23,2%). All patients were divided into subgroups 1 (n = 40) - survived during the 3-year, subgroups 2 (n = 33) - died during the 3-year follow-up period. The presence of RV dysfunction in patients with HFrEF was independently associated with concomitant LV dysfunction but not with PASP (PASP/GLSLV, % (р=0,94), PASP/FWLS RV, % (р=0,97). RV contractility was realized through systolic and diastolic ventricular interactions, mediated through the shared IVS. This putative mechanism was supported by the independent association between septal S’ and S (HR - 1,12; 95%; Cl 0,99-1,26; p = 0,049), GLS BS LV, % и FWLS BS RV, % (HR - 0,90; 95%; Cl 0,79-1,00; p = 0,040). Kaplan–Meier plot, RVFWS &amp;gt; -15%, (χ2 – 4,438; р &amp;lt; 0,035), GLS &amp;gt;-10%, (χ2 – 3,796; р&amp;lt; 0,05), RVBSLS &amp;gt;-15%, (χ2 – 11,986; р = 0,0005), 3DERVEF &amp;lt;25% (χ2 – 7,518; р = 0,006), %CVCI &amp;lt;30% (χ2 – 7,85; р = 0,005), 3DE RAV &amp;gt; 100 ml (χ2 – 4,36; р = 0,036) were an independent predictors of worse prognosis in patients with HFrHF. The curves of the ROC analysis demonstrated a sensitivity of GLSRV - 80.7% as a prognostic factor of survival in patients with HrEF. At the same time, FWLS RV had a specificity (87.5%) compared to GLSRV, %, the longitudinal deformation of the isolated segments of the FWRV, FAC, %VCI collapse, ESDA/SA of RV, RAV. Conclusions RV systolic dysfunction is a strong and independent predictor of in HFrEF. In case of HFrEF the longitudinal mechanism of RV reduction is more sensitive than others. GLSRV, FWS RV, 3DRVEF, %VCI collapse has been proposed as a more accurate and sensitive tool to evaluate RV function in longitudinal displacement of patients with HFrEF. Abstract Figure. Kaplan–Meier plot GLS, 3DEEFRV, FWLS Abstract Figure. ROC analysis

Evaluation of right and left ventricular function in patients with ischemic heart disease complicated by mitral insufficiency.

Aim To evaluate the right and left ventricular function and their interaction in patients with ischemic heart disease (IHD) complicated with mitral valve insufficiency (MVI) according to data of echocardiography (EchoCG) with the strain in gray scale, vector and diagram analyses.Material and methods The study included 118 patients evaluated with EchoCG at the preoperative stage of treatment; 71 of these patients had ischemic MVI (group 1) and 47 patients had uncomplicated IHD (group 2 or comparison group). Mean age of patients was 64±10 years. All patients underwent a surgery in an appropriate volume for myocardial revascularization supplemented with mitral valve plasty or replacement in patients with MVI. Standard EchoCG parameters and data obtained by postprocessing the EchoCG gray-scale images using the strain in gray scale, vector and diagram analyses were evaluated.Results In patients with complicated IHD, both global and local left ventricular (LV) systolic function and the right ventricular (RV) fractional area change (FAC) were significantly decreased. At the same time, there were no significant differences in the tricuspid annular plane systolic excursion (TAPSE) measured in M-mode and in the tricuspid annular systolic wave velocity (VSta), which also characterize the RV systolic function. The global longitudinal strain, the velocities of LV volume change and RV area change, and the long axis change velocity were informative for the right and left chambers, whereas the velocities of LV volume and RV area changes better detected RV disorders. The Pearson's correlation analysis used to identify the most significant parameters of interventricular interaction showed the presence of a strong inverse correlation, in the group of MVI patients, between the RV FAC and the degree of LV diastolic dysfunction (Е / e') - r= -0,62; p=0.000, as well аs the degree of MVI (vena contracta) - r= -0.58; p=0.001. In the comparison group of IHD patients without MVI, the correlation of RV FAC with E / e' was absent (r=0.28; p=0.192). The volume change velocity (dVol / dt) moderately correlated with the RV end-systolic and end-diastolic area in IHD patients but not in IHD patients with MVI. The RV area change velocity (dS / dt) evaluated during systole and diastole moderately significantly correlated with the LV end-diastolic volume.Conclusion Additional overload of left heart chambers in ischemic MVI is a factor that influences the development of the systemic and pulmonary circuit disorders. Recording and evaluation of global longitudinal strain, LV volume change velocity, and long axis change velocity with simultaneous recording of the segmental myocardial displacement velocity serve as highly informative criteria for disorders of LV and RV function. The vector analysis allows quantitative estimation of the local segmental myocardial function. Decreased velocities of the free RV wall segmental displacements during systole and diastole are characteristic of systolic and diastolic dysfunction in patients with IHD complicated with mitral regurgitation.

Mathematical modelling of atrial and ventricular pressure–volume dynamics and their change with heart rate

This paper presents mathematical models that can simulate the cardiovascular system of a healthy sheep under normal resting conditions in which the heart rate changes significantly. The models include several new modelling features that are introduced progressively. The contraction of the cardiac chambers is modelled using a time-dependent muscle force with constant elasticity instead of time dependent elasticity. A new hypothesis about the mechanical contraction of the atria generates realistic pressure volume (PV) loops. The inter-ventricular interaction is modelled as well. Additionally, hysteresis is incorporated in the aortic valve to produce an end-systolic reverse (negative) flow. Most of the model parameter values are based on previous literature data while time periods of delay, atrial and ventricular contraction are derived using experimental data from 14 sheep. We provide new relationships between contraction time and delay as a function of heart period. The effects of different aspects of our modelling on the mean cardiac output, stroke volume, ejection time, ejection fraction and PV loops are studied. Model outputs are compared with published experimental results where possible, and are within a wide range of physiological observations.

Assessment of Right Ventricular Function and Structure in Children with Idiopathic Dilated Cardiomyopathy

Background: Dilated cardiomyopathy (DCM) refers to dilating the ventricles and dysfunction of their systolic functions (predominantly the left ventricle) with or without congestive heart failure. In children, it is the most common form of heart muscle disease. We aimed to evaluate the right ventricular functions and structure using speckling tracking echocardiography in children with dilated cardiomyopathy and correlate this parameter with other echocardiographic findings.&#x0D; Methods: This observational Case-Control Study was carried out on 75 subjects. They were subdivided into two groups: Group 1: 50 patients with dilated cardiomyopathy Group 2: 25 healthy children matched for age and sex. Patients were evaluated by M-mode echocardiography, Transthoracic 2DE Examination (TTE), Tissue Doppler Examination (TDE) and Speckling Tracking Technique.&#x0D; Results: Left ventricle (LV) and right ventricle (RV) systolic dysfunction was evidenced by a significant decrease of mitral and tricuspid annular systolic velocities and a significant decrease of LV and RV global systolic strain and a significant decrease of LV and RV Ejection fraction (EF). LV and RV diastolic dysfunction were evidenced by a significant decrease of mitral and tricuspid annular diastolic velocities (E’/A’) and a significant increase of LV and RV Myocardial Perfusion Imaging (MPI). LV and RV global strains were significantly reduced in comparison to controls, suggesting that the dilated cardiomyopathy is a diffuse disease.&#x0D; Conclusion: In DCM patients, RV had significant systolic and diastolic dysfunction mainly elicited by the Tissue Doppler imaging (TDI) beside LV affection secondary to the interventricular interaction. TDI and 2D-STE add value to interpreting the findings and the dependency of RV systolic and diastolic functions on each other in DCM patients.

Cone Reconstruction for Ebstein Anomaly: Ventricular Remodeling and Preliminary Impact of Stem Cell Therapy

ObjectiveTo define the impact of tricuspid valve cone reconstruction (CR) on ventricular performance in Ebstein anomaly, both independently and after stem cell therapy. Patients and MethodsThe control group included 257 patients who had CR between June 2007 and December 2019. Ten subjects of a phase I stem cell therapy trial (May 2017 – March 2019) were compared with the controls to assess the echocardiographic impact on ventricular remodeling. ResultsAfter CR, right ventricular (RV) size decreased and left ventricular (LV) volume increased in all patients. Apical and biplane RV fractional area change (FAC) initially decreased, but rebounded by 6 months postoperation. Short-axis FAC increased early and was maintained at 6 months post-CR in the control group. At 6 months post-CR, cell therapy patients showed a significantly larger increase in short-axis FAC (24.4% vs 29.9%, P=.003). In addition, whereas LV ejection fraction (EF) was unchanged at 6 months post-CR in controls, cell therapy patients showed a significant increase in EF relative to baseline and to controls (55.6% vs 65.0%, P=.007). ConclusionCone reconstruction reduces tricuspid regurgitation and RV size, but is also associated with increased RV FAC and LV volume. Furthermore, injection of bone marrow–derived stem cells augmented the increase in RV FAC and was associated with improved LV EF at 6 months post-CR. This is evidence of a favorable interventricular interaction. These findings provide motivation for continued investigation into the potential benefits of stem cell therapy in Ebstein anomaly and other congenital cardiac malformations. Trial Registrationclinicaltrials.gov identifier: NCT02914171

Influence of right ventricular pressure and volume overload on right and left ventricular diastolic function

BackgroundVentricular interdependence may account for altered ventricular mechanics in congenital heart disease. The present study aimed to identify differences in load-dependent right ventricular (RV)–left ventricular (LV) interactions in porcine models of pulmonary stenosis (PS) and pulmonary insufficiency (PI) by invasive admittance-derived hemodynamics in conjunction with noninvasive cardiovascular magnetic resonance (CMR). MethodsSeventeen pigs were used in the study (7 with PS, 7 with PI, and 3 controls). Progressive PS was created by tightening a Teflon tape around the pulmonary artery, and PI was created by excising 2 leaflets of the pulmonary valve. Admittance catheterization data were obtained for the RV and LV at 10 to 12 weeks after model creation, with the animal ventilated under temporary diaphragm paralysis. CMR was performed in all animals immediately prior to pressure–volume catheterization. ResultsIn the PS group, RV contractility was increased, manifested by increased end-systolic elastance (mean difference, 1.29 mm Hg/mL; 95% confidence interval [CI], 0.57-2.00 mm Hg/mL). However, in the PI group, no significant changes were observed in RV systolic function despite significant changes in RV diastolic function. In the PS group, LV end-systolic volume was significantly lower compared with controls (mean difference, 25.1 mL; 95% CI, -40.5 to -90.7 mL), whereas in the PI group, the LV showed diastolic dysfunction, demonstrated by an elevated isovolumic relaxation constant and ventricular stiffness (mean difference, 0.03 mL−1; 95% CI, -0.02 to 0.09 mL−1). ConclusionsThe LV exhibits systolic dysfunction and noncompliance with PI. PS is associated with preserved LV systolic function and evidence of some LV diastolic dysfunction. Interventricular interactions influence LV filling and likely account for differential effects of RV pressure and volume overload on LV function.

Right Ventricular Pressure–Volume Analysis During Left Ventricular Assist Device Speed Optimization Studies: Insights Into Interventricular Interactions and Right Ventricular Failure

BackgroundInterventricular interaction, which refers to the impact of left ventricular (LV) function on right ventricular (RV) function and vice versa, has been implicated in the pathogenesis of RV failure in LV assist device (LVAD) recipients. We sought to understand more about interventricular interaction by quantifying changes in the RV systolic and diastolic function with varying LVAD speeds. Methods and ResultsFour patients (ages 22–69 years, 75% male, and 25% with ischemic cardiomyopathy) underwent a protocolized hemodynamic ramp test within 12 months of LVAD implantation where RV pressure–volume loops were recorded with a conductance catheter. The end-systolic PV relationship and end-diastolic PV relationship were compared using the V20 and V10 indices (volumes at which end-systolic PV relationship and end-diastolic PV relationship reach a pressure of 20 and 10 mm Hg, respectively). The ∆V20 and ∆V10 refer to the change in V20 and V10 from the minimum to maximum LVAD speeds. RV PV loops demonstrated variable changes in systolic and diastolic function with increasing LVAD speed. The end-systolic PV relationship changed in 1 patient (patient 2, ∆V20 = 23.5 mL), reflecting a decrease in systolic function with increased speed, and was unchanged in 3 patients (average ∆V20 = 7.4 mL). The end-diastolic PV relationship changed with increasing speed in 3 of 4 patients (average ∆V10 = 12.5 mL), indicating an increase in ventricular compliance, and remained unchanged in one participant (patient 1; ∆V10 = 4.0 mL). ConclusionsInterventricular interaction can improve RV compliance and impair systolic function, but the overall effect on RV performance in this pilot investigation is heterogeneous. Further research is required to understand which patient characteristics and hemodynamic parameters influence the net impact of interventricular interaction.

Cardiopulmonary hemodynamics and respiratory function in patients with chronic obstructive pulmonary disease according to doppler echocardiography data

Aim . Determination of the functional state of cardiopulmonary hemodynamics in patients with chronic obstructive pulmonary disease (COPD) with varying severity of bronchial obstruction and respiratory failure using echodopplercardiography. Materials and methods . In 82 patients with COPD, the functional state of cardiopulmonary hemodynamics was evaluated using ultrasound methods. All subjects were divided into 2 groups depending on the severity of COPD (moderate and severe course). Results . It was found that in patients with COPD, impaired diastolic function of the right ventricle (RV) may be preclinical. Thus, in patients with COPD stage 2, compared with control in the P-mode and tissue Doppler sonography (TDI), mild changes in the diastolic function (impaired relaxation) of the RV myocardium were revealed (E/A 0.70±0.13 and 1.56±0.18, E/Em 8.45±0.15 and 6.89±0.19, respectively). In patients with COPD stage 3, the mean values of these RV parameters significantly differed (E/A 0.69±0.04 and E/Em 9.34±0.18) and corresponded to moderately expressed diastolic dysfunction. Conclusions . In severe COPD in stage 3, significant violations of the structure and function of the RV were determined. The compensatory capabilities of both cardiac ventricles were depleted, the interventricular interaction changed, which created the conditions for the progression of heart failure and the development of chronic cor pulmonale.

The effect of pulmonary arterial hypertension specific treatment on the left ventricle in patients with pulmonary arterial hypertension

Abstract Background Pulmonary arterial hypertension (PAH) is characterized by right ventricular (RV) pressure overload, leading to RV dilation, failure and death. In the course of the disease, the left ventricle (LV) is often impaired, due to interventricular interaction. Although the impact of PAH treatment on the RV has been well described, less is known on the LV. Purpose To examine effects of advanced PAH treatments on the volumes, function and strain of the left atrium and ventricle. Methods This is a retrospective study. All patients underwent CMR and right heart catheterization, both at diagnosis and at 12-months follow up. Ventricular volumes and LV filling rate were calculated from the stack of short axis cine images using Simpsons method while left atrial (LA) volumes from the 4-chamber cine images using the area-length method. Tissue tracking was used for the evaluation of myocardial deformation. The LV endocardial and epicardial borders were manually delineated in all analysed sections with the initial contour set at end-diastole. All analyses were performed offline using dedicated software. Results In total, 66 patients (mean age 56.3±17.9 years, 67%women, 77%idiopathic and heritable PAH, 23% connective tissue disease associated PAH) and 29 normal controls were included. The improvement in metrics of right and left heart size and function after the initiation of advanced PAH treatment, are presented in panel A. Of note, LV stroke volume was markedly increased (54.6±19.6ml at baseline vs 70.8±21.7ml at follow up, p&amp;lt;0.0001) to reach controls. LV filling was markedly increased in latter two-thirds of the diastolic phase (panel B), especially at atrial kick point (arrow). Change in LA max volume was associated with changes in diastolic filling (r=0.354, p=0.004), LV end-diastolic and end-systolic volumes and stroke volume. These correlations were more robust in patients that increased LV filling compared to those that failed to increase LV filling (panels C-E). No association between changes in LV circumferential strain and LV volume load was observed. A weak correlation of change of LV peak longitudinal strain with stroke volume (r=−0.345, p=0.006), LV end diastolic volume (r=−0.284, p=0.027), LV ejection fraction (r=−0.337, p=0.008) and LA maximum area (r=−0.447, p&amp;lt;0.0001) was observed. The changes of LV strain showed no correlation with the changes in patients' haemodynamics. Conclusion Improvement in stroke volume after the initiation of advanced PAH treatment is associated with an increase in LA size, LV end diastolic volume and normalisation of strain. This reflects the improved filling state of the left ventricle and the potential of the left atrium to monitor treatment effects. Changes after PAH treatment Funding Acknowledgement Type of funding source: None

Systolic function of the left ventricle in patients with pulmonary hypertension on the background of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) greatly affects the quality of life, significantly limiting the physical capabilities of people suffering from it. The prevalence of COPD worldwide is about 7,6 %, and it is one of the main causes of morbidity and mortality in today’s society. An urgent medical and social problem of our time is the development of pulmonary hypertension (PH) in patients with COPD. Transthoracic echocardiography is important for PH screening. It has the highest sensitivity and specificity among non-invasive examinations, and unlike catheterization of the right heart, it does not require special equipment and centers for dynamic monitoring of patients with PH. When pulmonary hypertension, there is a pronounced remodeling of the heart. At the first stage, it occurs in the right parts of the heart, and in the future, as a consequence, it is accompanied by a violation of systolic inter-ventricular interactions.&#x0D; Purpose of the study. To determine the characteristics of left ventricular systolic function in patients with pulmonary hypertension on the background of COPD.&#x0D; Materials and methods. Results of the study are based on data from a comprehensive survey of 170 COPD patients aged 40 to 65 years, 123 of which had pulmonary hypertension and 47 ones had no pulmonary hypertension.&#x0D; Results and discussion. In the group of patients with PH on the background of COPD, the shock volume was 74,72 cm3 (64,60–83,09) and it was significantly lower compared to the level of 82,04 cm3 (75,20–87,76) of the COPD group without PH (p &lt; 0,05). Such echocardiographic index as left ventricular ejection fraction in groups of patients with COPD with PH and without it, was 57,59% (53,84–62,19) and 59,44% (56,67–61,88), respectively, and it was significantly lower compared to the level of 64,62% (62,86–67,91) of healthy individuals (p &lt; 0,05).&#x0D; There was a straight increase in end-diastolic volume and end-systolic volume in the subgroup of patients with COPD duration &gt; 12 years compared to the subgroup  12 years, 134,17 cm3 (117,00–150,15) versus 125,52 cm3 (105,20–139,60) and 57,37 cm3 (51,70–65,60) versus 51,40 cm3 (43,08–59,84),&#x0D; respectively (p &lt; 0,05). The impact volume had no significant differences between subgroups depending on the duration of COPD (p &gt; 0,05). The level of LV ejection fraction was significantly lower in the subgroup of COPD duration &gt; 12 years 56,64% (52,65–59,73) against the subgroup  12 years (p &lt; 0,05). There were no significant differences between the levels of systolic heart function indicators: end-diastolic volume, end-systolic volume, shock volume, and LV EF depending on the stage of COPD (p &gt; 0,05). Correlation analysis revealed significant relationships between the following indicators: duration of COPD and ESV (R = +0,24, p = 0,008); duration of COPD and LV EF (R = –0,25, p = 0,006); MPAP and EDV (R = –0,22, p = 0.02); MPAP and SV (R = –0,26, p = 0,004); MPAP and LV EF (R = –0,21, p = 0,02).

Increased systolic vorticity in the left ventricular outflow tract is associated with abnormal aortic flow formations in Tetralogy of Fallot.

Aortopathy is a recognized comorbidity of Tetralogy of Fallot (TOF). Aortic flow in children with repaired TOF is abnormal despite normal aortic valve anatomy and early surgical repair that results in aortic size normalization. The purpose of this study was to investigate the flow hemodynamics inside the left ventricle (LV) of children with repaired TOF using 4D-Flow MRI derived vorticity. Vorticity is the spatial derivative of flow velocity and is sensitive to anatomic and geometric variations. Vorticity was calculated inside the LV of children with repaired TOF having normal aortic size (n = 14) and normal controls (n = 10) during systolic ejection phase. All subjects underwent comprehensive biventricular analysis including the MRI based feature-tracking based LV strain analysis and mechanical dyssynchrony. Right ventricular (RV) volumetric indices along with LV mechanical indices were correlated with LV vorticity. All TOF patients had supraphysiologic helical flow in the ascending aorta. The generated peak systolic vorticity integrated over the LV volume was elevated in TOF group compared to control (median: 1344 vs. 858s-1, P < 0.001). TOF patients had increased LV mechanical dyssynchrony (47 ± 11 vs. 32 ± 7ms, P < 0.001) and reduced LV global circumferential strain (19 ± 2 vs. 21 ± 2%, P = 0.020). In the TOF group, LV systolic vorticity was independent of RV size and LV mechanical indices. Pathologic aortic flow in children with repaired TOF is associated with abnormal ejection flow patterns inside the LV. Increased systolic vorticity was not associated with LV mechanical dyssynchrony and RV dilation, suggesting that systolic flow inside the LV is independent of impaired LV contractile mechanics and inter-ventricular interactions.

Abnormal left ventricular flow organization following repair of tetralogy of Fallot

BackgroundLeft ventricular intracavitary flow (LVICF) characteristics reflect diastolic function. Right ventricular (RV) volume overload due to pulmonary regurgitation (PR) adversely impacts interventricular interactions and left ventricular (LV) function. This aimed to determine whether patients with PR and mild to moderate RV dilation after repair of tetralogy of Fallot (TOF) repair have abnormal LVICF, and to determine whether RV dilation and biventricular function correlate with LVICF abnormalities. MethodsPatients with repaired TOF with PR (n = 11) and controls (n = 11) underwent LVICF analysis. LV end-diastolic volume was partitioned into 4 flow components: direct flow, retained inflow, delayed ejection flow, and residual volume. Flow components were correlated with indexed biventricular size, function, and LV strain. ResultsThe TOF patients had reduced direct flow (35% vs 25%; P = .004) and increased residual volume (15% vs 24%; P = .026) compared with controls. Retained inflow and delayed ejection flow did not differ. Reduced direct flow correlated with increased RV end-diastolic volume index (R = 0.44; P = .042), RV end-systolic volume index (R = −0.46; P = .032), reduced RV ejection fraction (R = 0.45; P = .036), and reduced LV circumferential strain (R = 0.52; P = .014). Increased residual volume correlated with increased RV end-systolic volume index (R = 0.52; P = .013), reduced LV ejection fraction (R = −0.54; P = .010), and reduced LV circumferential strain (R = −0.44; P = .040). ConclusionsPatients with repaired TOF with mild to moderate RV dilation have abnormal LV diastolic direct flow and increased recirculating residual volume. These changes correlate with the degree of RV dilation and impaired LV function.