Left Ventricular Myocardial Mechanics Research Articles

Three-dimensional echocardiography and strain cardiac imaging in patients with prediabetes and type 2 diabetes mellitus.

Several studies using two-dimensional speckle tracking echocardiography (2D-STE) have confirmed the presence of left ventricular (LV) systolic dysfunction in patients with diabetes mellitus (DM), but there is a paucity of studies on whether three-dimensional (3D)-STE is superior to 2D-STE. The aim of this study was to evaluate the clinical value of 3D-STE in assessing subclinical LV systolic dysfunction in prediabetic and diabetic patients with preserved LV ejection fraction (LVEF) and to investigate the independent risk factors for this medical disorder. This study included 40 diabetic patients, 35 prediabetic patients, and 33 healthy volunteers. All participants underwent LV peak systolic strain analysis using 3D- and 2D-STE, and the receiver operating characteristic (ROC) curve was constructed to determine the clinical diagnostic value of strain parameters for evaluating subclinical LV dysfunction in patients with prediabetes and type 2 DM (T2DM). Regression models were established to analyze independent risk factors for subclinical LV systolic dysfunction in patients with prediabetes and diabetes. The results of the 3D-STE-based analysis showed that the global longitudinal strain (GLS) of the control, prediabetic, and diabetic groups were (18.64%±2.43%, 15.21%±1.49%, and 13.49%±2.36%, respectively), global circumferential strain (GCS) was (18.09%±2.37%, 14.62%±1.75%, and 12.95%±2.20%, respectively), global area strain (GAS) was (31.30%±3.88%, 27.51%±3.31%, and 24.80%±3.86%, respectively), and global radial strain (GRS) was (49.18%±5.91%, 39.17%±4.55%, and 35.72%±7.19%, respectively). All 3D-STE global strain parameters gradually decreased from the controls, through the prediabetic group to the diabetic group, and there was statistical significance between the three groups (P<0.001). The area under the curve (AUC) of the 3D-STE global strain parameters (GLS, GCS, GAS, and GRS) were 0.898, 0.831, 0.863, and 0.868, respectively. The AUC of the 2D-STE global strain parameters (GLS and GCS) were 0.867 and 0.636, respectively. Multivariate regression analysis identified increased glycosylated hemoglobin A1c (HbA1c) and body mass index (BMI) as independent risk factors for subclinical LV systolic dysfunction. Prediabetic and diabetic patients with preserved LVEF are at risk of subclinical LV systolic dysfunction. 3D-STE is a reliable imaging technique for evaluating early damage to LV myocardial mechanics. Early control of blood glucose (Glu) levels and weight can effectively prevent heart failure in the prediabetic and diabetic populations.

Abstract 14689: Evaluation of Left Myocardial Mechanics in Pediatric Heart Transplant Patients by Speckle Tracking Echocardiography

Objective: The aim of this study was to evaluate the left myocardial mechanics in pediatric heart transplant (PHT) patients after heart transplantation by three- dimensional speckle tracking echocardiography (3D-STE). Method: We retrospectively analyzed thirty-eight pediatric patient who underwent orthotopic heart transplantation from January, 2015 to December, 2021 at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. Clinical characteristics and conventional echocardiographic indices were described. 3D-STE were used to analyze myocardial mechanics in thirty-eight PHT patients. Left ventricular strain and rotational indices at 6 month and 1 year after heart transplant were obtained. Differences between left ventricular myocardial mechanic indices at 6 months and 1 year after heart transplant were analyzed and compared with normal reference range. Results: There were no statistically significant difference of LVGLS, LVGCS, LVGRS, 3D-apical peak rotation, 3D-basal peak rotation, 3D-peak twist, and 3D-peak torsion in PHT patients between 6 months and 1 year after heart transplantation( P &gt;0.05). Compared with 3D strain normal reference, 3D-LVGLS decreased and 3D-LVGCS increased in PHT patients at 6 months after transplantation( P &lt;0.05). Compared with 3D rotational normal reference, 3D-peak twist and 3D-peak torsion increased at 6 months after transplantation( P &lt;0.05). Conclusion: Compared with normal reference range, strain parameters were decreased and rotational parameters were increased. The study provided evidence for further investigations in establishing normal reference range of left ventricular myocardial mechanics in PHT patients and post-transplantation management of PHT patients.

The use of 2-D speckle tracking echocardiography in assessing adolescent athletes with left ventricular hypertrabeculation meeting the criteria for left ventricular non-compaction cardiomyopathy

BackgroundCurrent echocardiographic criteria cannot accurately differentiate exercise induced left ventricular (LV) hypertrabeculation in athletes from LV non-compaction cardiomyopathy (LVNC). This study aims to evaluate the role of speckle tracking echocardiography (STE) in characterising LV myocardial mechanics in healthy adolescent athletes with and without LVNC echocardiographic criteria. MethodsAdolescent athletes evaluated at three sports academies between 2014 and 2019 were considered for this observational study. Those meeting the Jenni criteria for LVNC (end-systolic non-compacted/compacted myocardium ratio > 2 in any short axis segment) were considered LVNC+ and the rest LVNC-. Peak systolic LV longitudinal strain (Sl), circumferential strain (Sc), rotation (Rot), corresponding strain rates (SRl/c) and segmental values were calculated and compared using a non-inferiority approach. ResultsA total of 417 participants were included, mean age 14.5 ± 1.7 years, of which 6.5% were LVNC+ (n = 27). None of the athletes showed any additional LVNC clinical criteria. All average Sl, SRl Sc, SRc and Rot values were no worse in the LVNC+ group compared to LVNC- (p values range 0.0003–0.06), apart from apical SRc (p = 0.2). All 54 segmental measurements (Sl/Sc SRl/SRc and Rot) had numerically comparable means in both LVNC+ and LVNC-, of which 69% were also statistically non-inferior. ConclusionsAmong healthy adolescent athletes, 6.5% met the echocardiographic criteria for LVNC, but showed normal LV STE parameters, in contrast to available data on paediatric LVNC describing abnormal myocardial function. STE could better characterise the myocardial mechanics of athletes with LV hypertrabeculation, thus allowing the transition from structural to functional LVNC diagnosis, especially in suspected physiological remodelling.

Evaluation of left ventricle systolic functions with 2D strain echocardiography after transcatheter aortic valve replacement in patients with severe aortic stenosis

ObjectiveThere is deterioration in global left ventricular (LV) longitudinal function in patients with severe aortic valve stenosis, and the decrease in LV global longitudinal strain (GLS) is associated with worsening prognosis. The aim of the study is to examine LV mechanical changes with LV strain imaging in addition to routine examination in patients who underwent transcatheter aortic valve replacement (TAVR). MethodsFifty patients who had been scheduled for the TAVR procedure between 2016 and 2018 were enrolled. The patients were evaluated before TAVR, 1 and 6 months after the procedure. The patients’ LV ejection fraction (LVEF), LVGLS, LV mass (LVM), LV mass index (LVMI), relative wall thickness (RWT), and left atrial volume index (LAVI) were calculated with transthoracic echocardiography. The patients’ performance scores were evaluated with Kansas City Cardiomyopathy Questionnaire (KCCQ-12). ResultsTwenty-six patients were female (52%), and the mean ages of patients were 75.30 ± 12.26 years. The mean LVEF of the patients was measured at 54.04 ± 13.48%, 58.10 ± 11.49%, and 59.36 ± 11.85 preprocedure and at first and 6 months, respectively. This increase in LVEF was statistically significant (p < 0.001). The mean LVGLS was measured −15.83 ± 2.78 preprocedure. The means of LVGLS were −18.73 ± 3.49 and −19.87 ± 4.05 at first and 6 months, respectively. Performance scores of patients significantly improved after the procedure (p < 0.001). The significant decreases in LVM, LVMI, RWT, and LAVI at 6 months compared to the preprocedural evaluation (p < 0.001). ConclusionIn severe aortic stenosis with deformation of LV myocardial mechanics, including GLS, a successful TAVR procedure provides a significant improvement in myocardial mechanics in early and midterm follow-up with.

Abstract 11382: Left and Right Ventricular Strain Mechanics in Fetal Arrhythmia

Introduction: Assessment of ventricular mechanics in fetuses with tachyarrhythmia poses significant challenges. Strain analysis measures myocardial deformation and has been shown to be a very sensitive marker of ventricular systolic dysfunction compared to traditional measurements. Global and regional myocardial deformation has not been well described in fetuses with arrhythmias. Hypothesis: We hypothesize that left and right ventricular myocardial mechanics are impaired in fetuses with tachyarrhythmias compared to normal fetuses in sinus rhythm. Methods: Retrospective review of fetuses with tachyarrhythmia (groups 1 and 2) and gestational age (GA) matched normal fetuses with normal cardiac anatomy (group 3) from 2000 to 2018 at a single institution, with IRB approval. Fetuses with isolated ectopy and congenital heart disease were excluded from all groups. Strain analysis was performed using VVI software. Arrhythmia type, medications, cardiovascular profile score and postnatal outcome were collected. Results: 18 fetuses with tachyarrhythmia with GA between 21 to 36.5 weeks were analyzed; 18 fetuses of similar GA with normal cardiac anatomy in sinus rhythm served as controls. 3 fetuses were delivered close to term and did not have strain assessment in sinus rhythm. Both LV global longitudinal strain (-4.44 ± 2.82%) and strain rate (-1.24 ± 0.85%) and RV global longitudinal strain (-6.76 ± 2.09%) and strain rate (-1.41 ± 0.55%) were reduced in tachyarrhythmia (Group 1) and recovered when in sinus rhythm (Group 2) but still reduced compared to controls (Group 3). Global longitudinal velocity was not different between patients in Group 2 and 3 (Table &amp; Fig 1). Conclusions: Strain parameters remain abnormal in fetuses with tachyarrhythmia despite conversion to sinus rhythm when compared to GA matched controls. Serial evaluation of strain will help guide therapy and monitor ventricular function in this patient population.

Abstract MP68: The Correlation Between Left Atrial-left Ventricular-arterial Coupling And Circadian Rhythm Of Blood Pressure In Hypertension

The Correlation between Left Atrial-Left Ventricular-Arterial Coupling and Circadian Rhythm of Blood Pressure in Hypertension Objective: Hypertension induces left atrial (LA) and left ventricular (LV) dysfunction, and arterial stiffness increased. In this study, we further investigated the association between LA-LV-arterial coupling and circadian rhythm of blood pressure (BP) in essential hypertension (HT). Design and Methods: We enrolled 289 HT patients which were evaluated by 2 dimensional speckle tracking echocardiography (2D-STE), ambulatory 24-hour BP monitoring (ABPM) and carotid-femoral pulse wave velocity (PWV). According to BP patterns, these patients were divided into two groups, which included dippers (n=109), patients with a &gt;10% reduction in BP at nighttime; non-dippers (n=180), patients with a &lt;10% reduction in BP at nighttime. 2D-STE based LA and LV strains were studied and the following parameters were measured, LV global longitudinal strain (GLS), LA reservoir strain (LA S-S ), LA conduit strain (LA S-E ), and LA booster pump strain (LA S-A ). LA stiffness index (LASI) defined as the ratio of E/e' to LA S-S , and PWV-to-GLS ratio (PWV/GLS) were calculated to reflect LA-LV-arterial coupling. Furthermore, we also explored the correlation between LASI (or PWV/GLS) and ambulatory blood pressure indexes. The related factors were evaluated by multivariate linear regression analysis to find the independent factors. Results: LASI was significantly higher in non-dippers (0.35±0.24) than dippers (0.29±0.12) ( p &lt;0.05). PWV/GLS was significantly higher in non-dippers (-90.30±34.13) than dippers (-79.62±25.84) ( p &lt;0.05). LA S-S , LA S-A and LV GLS were significantly lower in non-dippers than dippers ( p &lt;0.05). Multivariate linear regression analysis revealed that LV mass index (LVMI), PWV/GLS, nighttime mean SBP (n-SBP) and nighttime mean DBP (n-DBP) were independently correlated with LASI; LASI and n-SBP were independently correlated with PWV/GLS. Conclusions: LA and LV myocardial mechanics, and LA-LV-arterial coupling were associated with circadian rhythm of BP. Nocturnal systolic BP was the independent risk factor of abnormal LA-LV-arterial coupling in HT.

Right Ventricular-Pulmonary Arterial Coupling in Repaired Tetralogy of Fallot.

We assessed right ventricular (RV)-pulmonary arterial (PA) coupling in patients with repaired tetralogy of Fallot (TOF). Sixty patients (34 males) aged 18.6 ± 8.3years at 14.8 ± 7.4years after repair and 60 controls were studied. Two-dimensional, tissue Doppler and speckle tracking echocardiography and colour flow mapping were performed to assess RV end-systolic (ESA) and -diastolic areas, tricuspid valve Doppler and myocardial velocities, left ventricular (LV) and RV deformation and pulmonary (PR), tricuspid regurgitation (TR), respectively. The ratios of RV area change to ESA and peak tricuspid annular systolic (s) velocity to RV ESA indexed to body surface area reflected RV-PA coupling. Patients had greater RV areas and reduced tricuspid annular and myocardial velocities, LV and RV myocardial mechanics compared to controls (all p < 0.05). Both RV area change/ESA ratio and peak tricuspid annular s velocity/indexed RV ESA ratio were reduced in patients (all p < 0.001). Sixty-one and 100% of patients had, respectively, RV area change/ESA ratio and peak tricuspid annular s velocity/indexed RV ESA ratio < -2SD of controls. Indices of RV-PA coupling correlated positively with tricuspid myocardial velocities, LV and RV deformation and inversely with PR and TR (all p < 0.05). Multivariate analysis showed RV systolic strain rate, PR and TR as independent predictors of both RV-PA coupling indices, whilst age, gender and LV systolic strain were also predictors of peak tricuspid annular s velocity/indexed RV ESA ratio (all p < 0.05). In conclusion, RV-PA coupling is impaired and is associated with RV and LV mechanics and severity of PR and TR in patients with repaired TOF.

Evaluation of left ventricular myocardial mechanics in patients with normally functioning bicuspid aortic valves: A systematic review and meta-analysis.

Studies have found conflicting results concerning the left ventricular (LV) myocardial deformation properties in patients with normally functioning bicuspid aortic valves (BAVs). Whether the remodeling process of LV occurs independently in patients with BAV is a matter of debate. We searched PubMed, Embase, Cochrane library, and Web of Science for cohort studies aiming to assess LV function in adults with isolated BAV compared with tricuspid aortic valve (TAV) controls. Standard mean difference (SMD) was calculated from random-effects meta-analyses. Eight cohort studies were included. There were significantly lower global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS) in BAV than in TAV controls (GLS: SMD=0.64, 95% CI: 0.35 to 0.92, P<.0001; GRS: SMD=-0.71, 95% CI: -1.09 to -0.32, P=.0003; GCS: SMD=0.70, 95% CI: 0.41 to 0.98, P<.00001) and significantly higher left atrial volume index (LAVI) and E/e' in BAV than in TAV controls (LAVI: SMD=0.50, 95% Cl: 0.12 to 0.88, P=.01; E/e': SMD=0.54, 95% CI: 0.30 to 0.77, P<.00001). There was significantly higher Left ventricular mass index（LVMI） in BAV than in TAV controls (SMD=0.51, 95% CI: 0.24 to 0.79, P=.0003). Left ventricular ejection fraction (LVEF) was not significantly different between BAV patients and TAV controls (SMD=0.05, 95% CI: -0.16 to 0.26, P=.63). The impairment of LV myocardial mechanics, including LV systolic, diastolic dysfunction and LV hypertrophy, is present in patients with normally functioning BAV.This might support the hypothesis that BAV is not only a valvular disease but also a myocardial disease.

Strain Reversus: A Diagnostic Regional Myocardial Left Ventricular Longitudinal Strain Pattern in Tuberculous Constrictive Pericarditis on Two-Dimensional Speckle Tracking Echocardiography

Background: Tuberculous constrictive pericarditis (CP) is a chronic inflammatory disease by Mycobacterium tuberculosis affecting the pericardium, occurring mainly in developing nations. The aim of this study was to evaluate left atrial (LA) and left ventricular (LV) myocardial mechanics in tuberculous CP using standard two-dimensional (2D) echocardiography and speckle tracking echocardiography (STE). Methods: A prospective observational echocardiographic study of 30 subjects was performed: 15 patients with tuberculous CP and 15 controls. 2D echocardiography, color Doppler imaging, and tissue Doppler imaging (TDI) were performed along with STE to evaluate the LV and LA mechanics. Results: We found that the global circumferential strain (GCS, P = 0.002) and the global longitudinal strain (P = 0.02) were significantly reduced in patients with CP compared with controls. The longitudinal lateral wall strain was significantly reduced (P = 0.001) in CP patients, whereas longitudinal septal strain was not reduced significantly (P = 0.18) in CP patients compared with controls. The longitudinal lateral strain was significantly reduced as compared to the longitudinal septal strain (P = 0.001) within the CP group (strain reversus). Annulus reversus (medial early diastolic mitral annular velocity [e'] &gt; lateral e') by TDI was observed in 11 cases out of 15 in tuberculous CP group, whereas strain reversus (septal strain &gt; lateral strain) was seen in all cases of CP group. The LA reservoir strain showed a statistically significant reduction in CP patients (P = 0.001) compared to controls. Conclusions: “Strain reversus” and reduced GCS are characteristic imaging findings on STE in patients with tuberculous CP and may provide an additional parameter to conventional echocardiography in the diagnosis of tuberculous CP.

Effects of Sacubitril/Valsartan Treatment on Left Ventricular Myocardial Torsion Mechanics in Patients with Heart Failure Reduced Ejection Fraction 2D Speckle Tracking Echocardiography.

Background:Left ventricular ejection fraction (LVEF) is calculated from volumetric change without representing true myocardial properties. Strain echocardiography has been used to objectively measure myocardial deformation. Myocardial strain can give accurate information about intrinsic myocardial function, and it can be used to detect early-stage cardiovascular diseases, monitor myocardial changes with specific therapies, differentiate cardiomyopathies, and predict the prognosis of several cardiovascular diseases. Sacubitril/valsartan has been shown to improve mortality and reduce hospitalizations in patients with heart failure with reduced ejection fraction (HFrEF). The effect of sacubitril/valsartan angiotensin receptor neprilysin inhibitor (ARNI) on left ventricular (LV) ejection fraction (EF) and torsion dynamics in HFrEF patients has not been previously described.Methods:The study involved 73 patients with HFrEF, for all patients Full history was taken, full clinical examination was done. Baseline vital signs, ECG, NYHA classification, conventional echocardiography and STE were done at baseline study and after 6 and 11 months.Basal and apical LV short-axis images were acquired for further off-line analysis. Using commercially available two-dimensional strain software, apical, basal rotation, and LV torsion were calculated.Results:ARNI group of patients showed improvement of symptoms, LV global longitudinal strain (LVGLS)% and diastolic parameters including, E/A, E/e', TV, untwist onset and rate after 6 months of therapy in comparison to the traditionally treated patients. The improvement continued for 11 months with in additional significant improvement of systolic parameters in the form of LVGLS%, EF%, Twist, Apical and basal rotations, main dependent parameters for improvement of EF% was LVGLS% and Apical rotation.Conclusion:To the best of our knowledge, this is the first study to demonstrate that therapy with sacubitril/valsartan in HFrEF patients could create a state of gradual and chronic LV deloading which cause relieving of myocardial wall tensions and decreasing the LV end diastolic pressure this state could cause cardiac reverse remodeling and reestablishment of starling forces proprieties of LV myocardium, which lead to increase of LV EF.

Prominent involvement of basal left ventricular longitudinal strain in patients with monoclonal gammopathy of undetermined significance

Abstract Background In cardiac amyloidosis the application of Speckle Tracking Echocardiography allows to identify a specific left ventricular (LV) longitudinal strain (LS) pattern characterized by “apical sparing”, with a prominent involvement of basal and middle segments and normal LS of apical cap. The pattern of regional LS has been never investigated in monoclonal gammopathy of undetermined significance (MGUS), a condition which can predispose to cardiac amyloidosis. Purpose To compare LV regional LS patterns and LS base-to-apex behaviour of patients affected by MGUS in comparison with healthy subjects. Methods We enrolled 40 patients affected by MGUS (M/F=20/20; age 62.6±13.8 years), asymptomatic for cardiac symptoms, and a control group of 40 healthy subjects, matched for sex and age. Nineteen (47%) MGUS patients showed prevalent free K light chain and 21 (53%) had prevalent free λ light chain. Participants underwent standard echo-Doppler exam, including Speckle Tracking of the three apical views. Global longitudinal strain (GLS), the average LS of six basal (BLS), six middle (MLS), and six apical (ALS) segments (considered in absolute values) and relative regional strain ratio RRSR [=ALS/(BLS+MLS)] were computed. Exclusion criteria were overt heart failure, LV ejection fraction &amp;lt;53%, coronary artery and congenital heart disease, moderate to severe valvular disease, primary cardiomyopathies, atrial fibrillation and inadequate echo imaging. Results The two groups were comparable for body mass index, blood pressure and heart rate. LV mass index, relative wall thickness, left atrial volume index and Doppler-derived LV diastolic parameters did not differ significantly between the two groups. LV ejection fraction was also similar in MGUS and healthy controls. GLS resulted significantly lower in MGUS group than in controls (20.5±3.0 vs. 22.4±2.0%, p&amp;lt;0.02). BLS (17.1±3.7 vs. 19.2±2.2%, p=0.004), MLS (24.9±3.8 vs. 27.1±3.6%, p&amp;lt;0.01) and ALS (25.1±3.8 vs. 27.1±3.5%, p&amp;lt;0.01) were significantly lower in MGUS than in controls. The intergroup difference of RRSR (0.60±0.05 vs. 0.58±0.04) did not achieve the statistical significance (p=0.26) and none of the MGUS patients had RRSR&amp;gt;1. The figure depicts a LS bull'eye of a MGUS patient showing the prominent involvement of LV basal segments. Conclusions In presence of a normal LV ejection fraction, MGUS patients show a subclinical LV longitudinal systolic dysfunction. This is testified by a reduction of GLS and of regional LS which involves mainly LV basal segments, without substantial changes of relative regional strain ratio. LV regional longitudinal dysfunction could be useful to monitor LV myocardial mechanics during follow-up of MGUS patients. LS bull's eye in a MGUS patient Funding Acknowledgement Type of funding source: None

Value of left ventricular myocardial strain derived from cardiac magnetic resonance tissue tracking on differentiating constrictive pericarditis from restrictive cardiomyopathy

Objective: To compare left ventricular myocardial mechanics detected by cardiac magnetic resonance tissue tracking(CMR-TT) between patients with constrictive pericarditis(CP) and restrictive cardiomyopathy(RCM),and see if those can be used to differentiate CP from RCM patients. Methods: A total of 23 patients with CP, 20 patients with RCM, who hospitalized in Beijing Anzhen Hospital from January 2014 to April 2019 were included in this study and 25 healthy subjects served as control group, all subjects underwent cardiac magnetic resonance examination. Myocardial mechanics were evaluated by 2-dimensional(2D) and 3-dimensional(3D) CMR-TT in terms of global longitudinal strain(GLS), circumferential strain(GCS), radial strain(GRS) and the lateral wall strain to septal wall strain ratio(lateral/septal ratio) of basal, mid-cavity and apical. The diagnostic area under the receiver operating characteristic curve (ROC) was evaluated for differentiating CP from RCM. Results: Age, sex and heart rate were similar between CP and RCM patients(all P>0.05). 2D-GLS, 3D-GLS, GCS and GRS in CP and RCM groups were significantly lower than those in normal control group(all P<0.05).3D-GLS value was significantly lower in RCM patients than in CP patients(P<0.05), the area under the curve (AUC)=0.787(sensitivity 80%, specificity 78%). 3D-GCS was significantly lower in CP group than in RCM group(P<0.05), the AUC=0.737(sensitivity 80%, specificity 65%). However, there was no significant difference between CP and RCM in 3D-GRS(P>0.05). Compared with RCM, the circumferential and radial lateral/septal ratios of the basal were significantly lower in CP group than in RCM group(both P<0.05), AUC=0.737(sensitivity 70%, specificity 83%) and 0.737 (sensitivity 60%, specificity 87%), respectively. The left ventricular myocardial mechanics strain curve of the CP,RCM and normal control were different. The CP patients presented as " rapidly down-a platform" form, the RCM presented as "slowly down" form, and normal control presented as "rapidly down" form. Conclusion: Evaluating the differences in the diastolic process of left ventricular myocardium and left ventricular myocardial mechanics strain curve is helpful to differentiate CP from RCM patients.

Three-Dimensional Speckle Tracking Echocardiography for Assessment of Left Ventricular Function and Myocardial Mechanics after Pediatric Heart Transplantation

Three-dimensional (3D) echocardiography for the assessment of LV size, function and myocardial mechanics has been commonly used after heart transplantation (HT) in adults, but not yet in children. We purposed to explore the feasibility of 3D echocardiography for these parameters in children after HT. We analyzed data from 33 pediatric HT recipients with median age 10 yrs at HT (3 mos -17yrs) who had ≥ 2 echocardiograms with 3D LV full volume image within 24 hours of routine biopsy at BCH between March 2013 and December 2015. Rejection was defined by biopsy as acute cellular rejection Grade ≥2R or antibody mediated rejection (ISHLT-2004). We analyzed 3D LV volumes, ejection fraction (EF), mass and mass/volume, global longitudinal, circumferential and radial strains (GLS, GCS and GRS), twist and torsion at first, 6 and 12 months after HT; and compared with corresponding values in 30 age- and BSA-matched controls with median age 7.2 yrs (2 mos-17yrs). During the initial 30 days post HT, all HT recipients had smaller end-diastolic volumes than controls (median EDV: 38 vs. 47 ml/m2) resulting in mild LV hypertrophy (Mass: 50 vs. 43 gr/m2) and impairment in LV systolic function (EF: 56 vs. 65%, GLS: 21 vs. 26%, GCS: 26 vs. 33%, GRS: 39 vs. 48%, for all P<0.001). Among 23 rejection free recipients, EDV, ESV, Mass and GRS gradually increased within 1 year after HT (ANOVA P=0.015, P=0.022, P=0.015, P<0,001, respectively), while stroke volume, EF, GLS and GCS increased within 6 months (for all P≤0.008) and remained steady state through 1 year after HT. The initial mild LV hypertrophy decreased by 6 months after HT (mass/volume: P =0.028) without further changes until 1 year after HT CONCLUSION: 3D echocardiography can assess LV size, function and myocardial mechanics and reflects LV post-transplant recovery in rejection-free pediatric recipients. There were changes in LV size, function and myocardial mechanics associated with rejection and deserve further assessment in larger pediatric heart recipient cohorts.

The role of three-dimensional speckle tracking imaging in the diagnosis of immunoglobulin light-chain cardiac amyloidosis with normal left ventricular ejection fraction

Objective To explore the value of three-dimensional speckle tracking imaging (3D-STI) in the diagnosis of immunoglobulin light-chain cardiac amyloidosis(AL-CA) patients with normal left ventricular ejection fraction (LVEF). Methods A total of 92 consecutive patients diagnosed with systemic immunoglobulin light chain amyloidosis(sAL) and with normal LVEF from October 2014 to January 2018 in Xijing Hospital were enrolled.Based on the diagnostic criteria of cardiac involvement, the patients were divided into AL-CA group (52 cases) and immunoglobulin light chain amyloidosis (AL) group (40 cases). The clinical data and serological markers of the patients were collected, the conventional echocardiography and full-volume three dimensional dynamic images were acquired, left ventricular global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), and global area strain (GAS) were analyzed using off-line TomTec software. The differences between the two groups were compared. Results Compared with the AL group, the NT-proBNP of AL-CA group was significantly higher (P 0.05). Compared with the AL group, the maximal left ventricular wall thickness, left ventricular mass index, left atrial volume index, and E/e′ in the AL-CA group were significantly increased (all P 0.05). Compared with the AL group, GLS, GAS, and GRS were significantly lower in AL-CA group (all P 0.05). The ROC curve analysis showed that the cut-off values discriminating cardiac involvement were 16.09% for GLS, 36.54% for GAS and 31.90% for GRS. Conclusions 3D-STI measurements of left ventricular myocardial mechanics could detect cardiac involvement in patients with sAL amyloidosis, and provides a new method for diagnosis of AL-CA. Key words: Echocardiography; Three-dimensional speckle tracking imaging; Immunoglobulin light-chain cardiac amyloidosis; Strain

Myocardial Mechanics Parameters That Predict Left Ventricular Outflow Tract Obstruction in Patients With Hypertrophic Cardiomyopathy: A Cardiovascular Magnetic Resonance Feature Tracking Analysis.

To identify left ventricular (LV) myocardial mechanics predictors of LV outflow tract obstruction (LVOTO) in patients with hypertrophic cardiomyopathy (HCM). Thirty-nine adults with HCM and 21 controls underwent cardiovascular magnetic resonance. The feature tracking (FT) analysis results of HCM patients with and without LVOTO and controls were compared. Global radial strain measured on the short-axis slice (GRS-SAX) (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.02-1.15; P < 0.01), global longitudinal strain measured on the long-axis slice (GLS-LAX) (OR, 1.81; 95% CI, 1.21-2.73; P < 0.01) and GRS measured on the long-axis slice (GRS-LAX) (OR, 1.07; 95% CI, 1.01-1.13; P = 0.02) were independent predictors of LVOTO. The combination of GRS-SAX plus GLS-LAX and GRS-LAX showed great discriminatory power for identifying LVOTO with an area under the receiver operating characteristic curve value of 0.91 (95% CI: 0.81-1.00). In adult HCM patients, GRS-SAX, GLS-LAX, and GRS-LAX were independent predictors of LVOTO. The combination of GRS-SAX plus GLS-LAX and GRS-LAX showed great discriminatory power for identifying LVOTO.

710 The Effect of Mitral Valve Surgery on Left Ventricular Remodelling and Function in Paediatric Patients With Rheumatic Heart Disease: An Echocardiographic Study

Rheumatic heart disease (RHD) commonly results in mitral regurgitation (MR). The effects of left ventricular (LV) volume loading and alleviation on LV remodelling remains incompletely studied in children. MR in RHD allows investigation of haemodynamic measures without confounding congenital heart disease. We assessed the effects of MR and repair on LV myocardial mechanics, remodelling and function in children with RHD. Paediatric patients who underwent mitral valve repair or replacement for isolated RHD-MR from 2004 to 2019 with adequate echocardiographic studies were retrospectively assessed pre- and postoperatively and compared to matched controls. Eighteen patients underwent mitral valve surgery during the study period. Postoperatively there was a significant reduction in left atrial (LA) (p=0.001) and LV end-diastolic M-mode dimensions (p=0.001) and volumes (p=0.006), with no change in LV end-systolic volumes, yielding a significant reduction in LV functional measures (fractional shortening (34.5 vs 31.5%, p=0.006), four-chamber ejection fraction (62.6 vs 51.7%, p=0.002) and LV longitudinal strain (-24.3 vs -18.2%, p<0.001). Compared to controls, LA and LV dimensions remained increased with a reduction in all functional parameters after repair. There was a moderate negative correlation between preoperative end-diastolic volumes and postoperative longitudinal strain (r2=0.35). Persistent LV and LA remodelling with decreased LV function is observed after repair of RHD-MR. While these results reflect changes to volume loading, the unmasking of decreased LV function and persistent remodelling; and linear relation to preoperative LV size, may suggest that early intervention to alleviate MR could benefit selected patients and warrants further study.

Quantification of left ventricular performance in different phenotypes of hypertrophic cardiomyopathy

Objective To evaluate the characteristics of left ventricular structure, function, myocardial mechanics, hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy (HCM) using state-of-the-art echocardiography. Methods A consecutive series of 85 adult HCM patients who were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected. According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography, the patients were divided into three groups: patients with non-obstructive HCM (n=28), those with labile-obstructive HCM (n=27), and those with obstructive HCM (n=30). In addition, 16 normal family members of HCM patients were included as control group. Two-dimensional speckle tracking imaging, tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states. Results ①As compared with the control group, left ventricular end-diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups(all P 0.05). The obstructive HCM had the lowest mitral annular plane systolic excursion (MAPSE) and s′, and the longest systolic peaking time standard deviation(Ts-SD) and early diastolic peaking time standard deviation(Te-SD) (all P<0.05). The left ventricular diastolic function of obstructive HCM (e′, the E/e′ ratio and the left atrial volume index) was the worst, labile-obstruction and non-obstructive HCM were better, and the control group was the best (all P<0.001). ③During exercise, the GLS, GCS, GRS, twist of the left ventricle and the MAPSE were the lowest in the obstructive HCM, which increased in the labile-obstructive and non-obstructive HCM, and were best in the control group. The Ts-SD and Te-SD were the shortest in the control group, were prolonged in non-obstructive and labile-obstruction HCM, and were longest in obstructive HCM (all P<0.05). Additionally, the exercise time of the control group was the longest, followed by non-obstructive and labile-obstruction HCM, and the shortest in the obstructive HCM (all P<0.05). The METs of obstructive HCM were significantly lower than the other three groups (all P<0.05). Conclusions In obstructive HCM, the left ventricular systolic strain and synchronization, as well as the MAPSE, are significantly impaired in patients both at rest and during exercise. The patients with labile-obstructive and non-obstructive HCM have reduced left ventricular GLS, twist, and e′, but normal left ventricular GCS, GRS, synchrony, and MAPSE at rest, which are all impaired during exercise. Key words: Two-dimensional speckle tracking imaging; Tissue Doppler imaging; Hypertrophic cardiomyopathy; Exercise stress echocardiography; Myocardial mechanics; Synchrony

ALTERATIONS IN LEFT ATRIAL AND LEFT VENTRICULAR MYOCARDIAL FUNCTION IN MIXED AORTIC VALVE DISEASE

Patients with mixed aortic valve disease (MAVD; combined moderate or > aortic stenosis (AS) and moderate or > aortic regurgitation) have poorer outcomes compared to those with isolated severe AS. Little is known of the impact of MAVD on left atrial (LA) and left ventricular (LV) myocardial mechanics. We aim to characterize LA and LV myocardial function in MAVD patients. We retrospectively identified 184 patients, 35 moderate MAVD (moderate AS and moderate aortic regurgitation), 40 severe MAVD (severe AS and moderate aortic regurgitation), 33 isolated severe AS, 31 isolated severe aortic regurgitation, and 45 controls, who underwent transthoracic echocardiogram. Simultaneous speckle-tracking longitudinal strain (LS) analysis of the LA and LV were performed on the apical 4-chamber view (EchoInsight, Epsilon) to obtain LV peak LS and LA peak, contractile, and conduit strain. ANOVA with post-hoc Tukey’s test was used to compare groups. P < 0.05 was considered significant. Results are presented in Table 1. Compared to controls, LV peak LS was significantly reduced in moderate MAVD, severe MAVD and severe AS patients. LV peak LS was not significantly different between moderate MAVD and severe AS patients but was significantly lower in the severe MAVD group. Severe aortic regurgitation patients had higher peak LS compared to controls, moderate MAVD, severe MAVD and severe AS patients. LA peak, conduit and contractile strains were significantly reduced in moderate MAVD, severe MAVD and severe AS patients compared to controls and severe aortic regurgitation patients. LA peak and contractile strains were not different between the moderate MAVD, severe MAVD or severe AS groups. However, LA conduit strain was significantly reduced in those with severe MAVD compared to the moderate MAVD but not the severe AS group. The severe aortic regurgitation group had preserved LA peak, conduit and contractile strain compared to the other groups. Moderate MAVD patients have a reduction in LV and LA myocardial function comparable to isolated severe AS patients. Severe MAVD patients have a greater decline in LV peak LS and LA conduit strain compared to moderate MAVD or severe AS patients. These changes may contribute to the poorer outcomes observed in MAVD patients.

Physiological left ventricular segmental myocardial mechanics: Multiparametric polar mapping to determine intraventricular gradients of myocardial dynamics.

We investigated physiological systolic left ventricular (LV) myocardial mechanics and gradients to provide a database for later studies of diseased hearts. The analyses were performed in 131 heart-healthy individuals and included seven parameters of myocardial mechanics using speckle tracking echocardiography (STE). Basal to apical and circumferentially significant physiological intraventricular parameter gradients of myocardial activity were determined. Global mean values and segmental ranges were peak systolic longitudinal strain -21.2±3.3%, 95% confidence interval [CI] -21.8% to -20.6%), gradient (basal to apical) -16.0% to -26.7%; peak systolic longitudinal strain rate -1.24±0.31%/s, 95% CI -1.29% to -1.19%/s, gradient (basal to apical) -0.91% to -1.61%/s; post-systolic index 2.6±3.2%, 95% CI 3.15%-2.05%, gradient (basal/medial/apical) 7.0/1.2/2.4%; pre-systolic stretch index 1.3±2.7%, 95% CI 1.77%-0.83%, gradient (basal/medial/apical) 6.5/0.2/1.3%; peak longitudinal displacement 12.2±2.6mm, 95% CI 12.6-11.8mm, gradient (basal to apical) 21.0-3.4mm; time-to-peak longitudinal strain 370±43ms, 95% CI 377-363ms, gradient (basal to apical) 396-361ms; and time-to-peak longitudinal strain rate 180±47ms, 95% CI 188-172ms, gradient (basal to apical) 150-200ms. This study generated a database of seven STE-derived parameters of physiological segmental and global myocardial LV mechanics. The resulting sets of three-dimensional intraventricular mappings of the entire LV provide physiological parameter gradients in baso-apical and circumferential direction by applying the 17-segment polar model. This will facilitate comparison of systolic myocardial activity of the healthy LV with diseased or otherwise altered (eg, sports) hearts.

Effects of different ultrasound power application on left ventricular myocardium synchrony in vivo open-chest Beagle canines

Objective To evaluate left ventricular (LV) myocardial mechanical synchrony with contrast agent and different power irradiation in open-chest Beagle canines. Methods The anesthetized open-chest Beagle canines were assigned into two groups randomly: Group A (n=6) for baseline, diagnostic ultrasound power irradiation (300 mW) 5 min, combined with contrast agent irradiation 5 min and contrast agent 20 min conditions; Group B (n=6) for baseline and intensity ultrasound irradiation (1 W, 2 W and 3 W, 5 min respectively) conditions. The standard short-axis gray-scale views at levels of mitral annulus (MV), papillary muscle(PM), and apex(AP) during 3 complete cardiac cycles in open-chest Beagle canine models were acquired. The global radial displacement peak time (RD-PT) and standard deviation of peak time (RD-PTSD) of LV subendomyocardium (subendo) and subepimyocardium (subepi) were measured and analyzed by using a dedicated Syngo velocity vector imaging (VVI) method. Results In group A, compared with baseline condition, the RD-PT and RD-PTSD of subendo and subepi had no significant different among diagnostic power irradiation, contrast agent irradiation 5 min and contrast agent 20 min (all P<0.05). There was no significant different in the RD-PT and RD-PTSD between subendo and subepi in A group in all conditions (all P<0.05). In group B, the RD-PT and RD-PTSD of subendo and subepi with power 1 W, 2 W and 3 W was higher than those with baseline condition; the RD-PT and RD-PTSD of subendo were significant different on 2 W compared with those on baseline condition (all P<0.05); the RD-PT and RD-PTSD of subendo, subepi were significant different on 3 W compared with baseline condition (all P<0.05); the RD-PT and RD-PTSD were significant difference between subendo and subepi in only 3 W condition (all P<0.05). Conclusions Diagnostic ultrasound power irradiation 5 min and combined with contrast agent irradiation 5 min and contrast agent 20 min conditions do not effect the synchrony of LV myocardial mechanics. Power more than 1 W can induce the delay of RD-PT and RD-PTSD of LV subendo and subepi. Power 3 W can result in dyssynchrony of LV myocardial mechanics. Key words: Sonication; Ventricular function, left; Beagle canines; Synchrony