End-diastolic Length Research Articles

Glucose control during pregnancy in patients with type 1 diabetes correlates with fetal hemodynamics: a prospective longitudinal study

BackgroundMaternal diabetes adversely affects fetal cardiovascular system development. Previous studies have reported that the fetuses of mothers with diabetes exhibit both structural and functional changes; nevertheless, prior studies have not examined the association between glucose control and fetal cardiac morphology and performance. Thus, the objective was to determine the association between fetal cardiac morphology and function and maternal glucose control in type 1 diabetes and to compare the differences in measured cardiac parameters between the fetuses of mothers with diabetes and healthy controls.MethodsIn this prospective, longitudinal case-control study — including 62 pregnant women with type 1 diabetes mellitus and 30 healthy pregnant women — fetal cardiac assessment using B-mode, M-mode, and spectral pulsed-wave Doppler was performed in the second and third trimesters. In women with T1DM, glycated hemoglobin and data obtained from glucose sensors — including the percentage of time in, below, and above the range (TIR, TBR, and TAR, respectively), and coefficient of variation (CV) — were analyzed across three time periods: the last menstrual period to 13 (V1), 14–22 (V2), and 23–32 weeks (V3) of gestation. Fetal cardiac indices were compared between groups, and the correlation between glucose control and fetal cardiac indices was assessed.ResultsAt 28–32 weeks, the fetuses of women with T1DM exhibited increased left ventricular end-diastolic length, relative interventricular septum thickness, right ventricular cardiac output, and pulmonary valve peak systolic velocity compared with healthy controls. At 18–22 weeks, pulmonary and aortic valve diameters, left and right ventricular stroke volumes, and left cardiac output inversely correlated with the CV and glycated hemoglobin levels at V1 and V2. Furthermore, at 28–32 weeks, pulmonary and aortic valve diameters, left ventricular stroke volume, cardiac output, and right/left atrioventricular valve ratio inversely correlated with the TBR at V1, V2, and V3. Moreover, diastolic functional parameters correlated with the TAR and glycated hemoglobin levels, particularly after the first trimester.ConclusionIn women with T1DM, maternal hyperglycemia during pregnancy correlates with fetal diastolic function, whereas glucose variability and hypoglycemia inversely correlate with fetal left ventricular systolic function in the second and third trimesters.

Echocardiographic assessment of right ventricular function and right ventriculoarterial coupling in tricuspid regurgitation

Abstract Funding Acknowledgements Type of funding sources: None. Background Echocardiographic evaluation of the cardiopulmonary unit may be difficult in the presence of tricuspid regurgitation (TR) and combined echocardiographic parameters could therefore be useful in such patients. Purpose To assess the variation of simple and combined echocardiographic parameters analysing the cardiopulmonary unit according to the severity of TR. Methods Echocardiographic images were reviewed in 179 patients to assess TR grade according to Hahn’s 5 grades classification. Classical morphological (right ventricle (RV) end diastolic (ED) length and area), function (tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (RVFAC), S’ wave, RV free wall longitudinal strain (RVFWS)) and load (TR Time-velocity integral (TR TVI), pulmonary artery systolic pressure (PASP)) parameters analysing RV were assessed. Combined parameters of function and load (TAPSE/PASP, TR TVI x RVFWS), morphology and load (load adaptation index (LAI) = TR TVI x RVED length/area) and morphology, load, and function (myomechanical index (MMI = RV-RA mean pressure gradient x RVFWS/indexed RAED area x 10–2 ) and morphology-load-function index (MLF = RVED length/area x TR TVI x RVFWS)) were calculated. We used receiver operating characteristic (ROC) curve analysis to analyze the diagnostic value of echocardiographic parameters to predict potential high (>3) or low (<6) surgical risk of mortality according to TRISCORE. Results Simple parameters were significatively different among groups with a nonlinear progression between the 5 levels of severity of TR. Combined parameters were also significatively different among groups. Among them, MMI and MLF had a linear progression between the 5 groups (MMI: grade 1: 0.20±0.09; grade 2: 0.15±0.08; grade 3: 0.10±0.05, grade 4: 0.09±0.08; grade 5: 0.05±0.04 p = 0.000; MLF: grade 1: 7.56±2.06; grade 2: 6.57±2.14; grade 3: 4.85±2.29, grade 4: 4.79±3.17; grade 5: 3.06±1.82 p = 0.000) and had the best predictive value for TRISCORE high and low risk (MMI: AUC =0.889 p = 0.000 for low risk, 0.855 p = 0.000 for high risk; MLF: AUC =0.873 p = 0.000 for low risk, 0.822 p = 0.000 for high risk). Conclusion Combined parameters are relevant to evaluate cardiopulmonary unit in a population presenting with TR, especially when combining morphology, function and load parameters. Their good predictive value for TRISCORE risk suggests a potential role of such parameters in the prognostic assessment of TR patients and in the selection for new percutaneous repair techniques.

Echocardiographic assessment of right ventricular function and right ventriculoarterial coupling in tricuspid regurgitation

Echographic evaluation of the cardiopulmonary unit may be difficult in the presence of TR. Purpose: To assess the variation of simple and combined echographic parameters analysing the cardiopulmonary unit according to the severity of TR. Echographic images were reviewed in 179 patients to assess TR grade according to Hahn's 5 grades classification. Classical morphological (RV end diastolic length and area), function [TAPSE, RVFAC, S’,RVFWS (RV free wall longitudinal strain)] and load [PASP,TRTVI (TR Time-velocity integral)] parameters analysing RV were assessed. Combined parameters of function and load (TAPSE/PASP, TR TVI × RVFWS), morphology and load (load adaptation index = TRTVIxRVED length/area) and morphology, load, and function [myomechanical index (MMI = RV-RA mean pressure gradient × RVFWS/indexed RAED area × 10–2) and morphology-load-function index (MLF = RVED length/area xTRTVIx RVFWS)] were calculated. We used ROC curves to analyze the diagnostic value of echocardiographic parameters to predict potential high (> 3) or low (< 6) surgical risk of mortality according to TRISCORE. Simple parameters were significatively different among groups with a nonlinear progression between the 5 levels of TR. Combined parameters were also significatively different. Among them, MMI and MLF had a linear progression (MMI: grade 1: 0.20 ± 0.09; grade 2: 0.15 ± 0.08; grade 3: 0.10 ± 0.05, grade 4: 0.09 ± 0.08; grade 5: 0.05 ± 0.04 P = 0.000; MLF: grade 1: 7.56 ± 2.06; grade 2: 6.57 ± 2.14; grade 3: 4.85 ± 2.29, grade 4: 4.79 ± 3.17; grade 5: 3.06 ± 1.82 P = 0.000) and had the best predictive value for TRISCORE (MMI: AUC = 0.889 P = 0.000 for low risk, 0.855 P = 0.000 for high risk; MLF: AUC = 0.873 P = 0.000 and 0.822 P = 0.000). Combined parameters are relevant to evaluate cardiopulmonary unit in a population presenting with TR, especially when combining morphology, function and load (Fig. 1).

Echocardiographic reference z scores of right ventricular dimension and systolic function of children aged 5-12 years.

Reference values for right ventricular dimension and systolic function in Nigerian children are scarce despite their high burden of right ventricular abnormalities. Reference values from other countries may not be suitable for use in Nigerian children because of possible racial variations in cardiac size. To develop reference values for right ventricular dimension and systolic function in healthy Nigerian children aged 5-12 years. This descriptive cross-sectional study conducted between July and November 2019 included 480 healthy boys and girls aged 5-12 years. The participants were randomly selected from 6 primary schools in the Ikeja Local Government area of Lagos State and their weights and heights measured. Body mass index and body surface area were calculated. Echocardiography was performed at rest in the left lateral position. The right ventricular end-diastolic basal diameter (RVD1), right ventricular end-diastolic mid-cavity diameter (RVD2), and right ventricular end-diastolic length (RVD3) were obtained. The right ventricular end-diastolic basal diameter (RVD1), right ventricular end-diastolic mid-cavity diameter (RVD2), and right ventricular end-diastolic length (RVD3) were obtained, as well as tricuspid annular plane systolic excursion (TAPSE) and tissue Doppler-derived right ventricular systolic excursion velocity (S'). The overall mean±standard deviation (SD) values for RVD1, RVD2, RVD3, TAPSE, and S' were 32.95±4.2, 25.86±3.5, 54.57±7.5, 20.11±2.3, and 18.24±2.2, respectively. Age- and sex-specific mean and SD values of the same cardiac indices were determined. Z score charts and the mean± 2SD right ventricular dimensions and systolic function were generated. All right ventricular dimensions were positively correlated with weight, height, body surface area, and body mass index. Only height correlated consistently with TAPSE and S'. The observed mean right ventricular dimension indices differed from those derived elsewhere, suggesting that values from other countries may be inappropriate for Nigerian children. These reference values are applicable in daily clinical practice.

Comparison of the left and right ventricular size and systolic function of low-risk fetuses in the third trimester: Which is more dominant?

To quantify fetal cardiovascular parameters utilizing fetal-specific 2D speckle tracking technique and to explore the differences in size and systolic function of the left and right ventricles in low-risk pregnancy. A prospective cohort study was performed in 453 low-risk single fetuses (28+0-39+6 weeks) to evaluate ventricular size [i.e., end-diastolic length (EDL), end-systolic length (ESL), end-diastolic diameter (ED), end-systolic diameter (ES), end-diastolic area, end-systolic area, end-diastolic volume (EDV), and end-systolic volume (ESV)] and systolic function [i.e., ejection fraction (EF), stroke volume (SV), cardiac output (CO), cardiac output per kilogram (CO/KG), and stroke volume per kilogram (SV/KG)]. This study showed that (1) the reproducibility of the interobserver and intraobserver measurements was good to excellent (ICC 0.626-0.936); (2) with advancing gestation, fetal ventricular size and systolic function increased, whereas right ventricular (RV) EF decreased and left ventricular (LV) EF was not significantly changed; (3) LV length was longer than RV length in diastole (2.24 vs. 1.96 cm, P < 0.001) and systole (1.72 vs. 1.52 cm, P < 0.001); (4) LV ED-S1 and ES-S1 were shorter than the RV ED-S1 and ES-S1 (12.87 vs. 13.43 mm, P < 0.001; 5.09 vs. 5.61 mm, P < 0.001); (5) there were no differences between the LV and RV in EDA or EDV; (6) the mean EDV ratio of right-to-left ventricle was 1.076 (95% CI, 1.038-1.114), and the mean ESV ratio was 1.628 (95% CI, 1.555-1.701); (7) the EF, CO and SV of the LV were greater than the RV (EF: 62.69% vs. 46.09%, P < 0.001; CO: 167.85 vs. 128.69 ml, P < 0.001; SV: 1.18 vs. 0.88 ml, P < 0.001); (8) SV and CO increased with ED-S1 and EDL, but EF was not significantly changed. Low-risk fetal cardiovascular physiology is characterized by a larger RV volume (especially after 32 weeks) and greater LV outputs (EF, CO, SV, SV/KG and CO/KG).

Abstract 14791: Evaluation of Cardiac Size, Shape and Function in Fetuses With Coarctation of the Aorta by Fetal Heart Quantitative Technique

Introduction: This study aimed to evaluate the size and shape of the four-chamber view (4CV) and right and left ventricles (RV and LV) as well as the function of the RV and LV in fetuses with coarctation of the aorta (CoA) using fetal heart quantitative (Fetal HQ) technique. Methods: A total of 67 CoA fetuses and 67 gestational age-matched controls were included. Fetal HQ technique was used to obtain the 4CV end-diastolic (ED) width, length, area, and global sphericity index (GSI), RV and LV 24-segment ED diameter (EDD), 24-segment sphericity index (SI), area, and the following functional parameters: (1) fractional area change (FAC); (2) global longitudinal strain (GLS); (3) 24-segment transverse fractional shortening (FS); (4) LV ejection fraction (LVEF), LV ED volume (LVEDV), LV stroke volume (LVSV) and LV output (LVO). Results: Compared with normal controls, the Z-score of 4CV ED width was increased ( P &lt; 0.05), while the GSI was decreased ( P &lt; 0.05) in fetuses with CoA. However, there were no significant differences in the Z-scores of 4CV ED length and area between two groups (both P &gt; 0.05) The RV 24-segment EDD Z-scores, RV area Z-score as well as the RV/LV 24-segment EDD were significantly higher in CoA fetuses than in controls (all P &lt; 0.05). In contrast, the LV 24-segment EDD Z-scores and area Z-score were significantly lower in fetuses with CoA ( P &lt; 0.05). The 24-segment SIs of the LV were significantly higher, while the 24-segment SIs of the RV were significantly lower in CoA group (all P &lt; 0.05). CoA fetuses presented lower GLS, FAC and 24-segment FSs for both RV and LV when compared with normal controls (all P &lt; 0.05). In addition, LVEF, LVEDV Z-score, LVSV Z-score and LVO Z-score were all decreased in CoA fetuses (all P &lt; 0.05). Conclusions: In fetuses with CoA, the 4CV was increased in width and spherical in shape. The LV area and width were decreased, while the transverse width and area of RV was increased. Abnormal SIs reflected a flatter LV and a more spherical RV. RV and LV global, longitudinal, and transverse contractility were all depressed. Fetal HQ can be used to quantitatively analyze cardiac size, shape and function in CoA fetuses, which may improve prenatal diagnosis of CoA.

Assessment of the Size and Shape of the 4-Chamber View and the Right and Left Ventricles Using Fetal Speckle Tracking in Normal Fetuses at 17–24 Gestational Weeks

Introduction: The aim of the study was to establish normal reference values obtained by fetal speckle tracking analysis of the fetal heart between 17 and 24 weeks of gestation among Thai fetuses and compare the nomograms with previous studies. Methods: The 4-chamber view (4CV) of the fetal heart in 79 normal fetuses was analyzed by speckle tracking analysis to determine the best-fit regression model. The 95% reference intervals and Z-score equations of fetal cardiac parameters were computed. Results: The end-diastolic length, width, area, and circumference of the 4CV as well as the ventricular end-diastolic length, 24-segment widths, and area were all increased as a function of gestational age (GA), and 5 fetal biometric parameters. In contrast, the global sphericity index (SI), 24-segment SI, and right ventricle/left ventricle width and area ratios did not change with GA or fetal biometric measurements. There were few differences in Z-score reference ranges of fetal cardiac measurements between the current study and previous studies conducted in different patient populations. Conclusion: Our study provided z-score and corresponding centile calculators, 5th and 95th centile reference tables, and corresponding graphs for evaluating the size and shape of the 4CV and the right and left ventricles using 6 independent variables between 17 and 24 weeks of gestation. These results provide normal reference ranges for future studies of fetuses with pathologies that may alter the size and shape of the 4CV and ventricles.

Echocardiographic predictors of outcome after tricuspid valve surgery

Mortality of isolated tricuspid surgery is high, close to 10%. We aimed to assess prognostic value of echocardiographic parameters among patients who underwent tricuspid valvular surgery. Preoperative echocardiograms were retrospectively reviewed in 75 patients (33 males, mean age 54 ± 17 years) hospitalized between 2007 and 2020. Parameters of right heart morphology including RV remodelling index: mid RV end diastolic (ED) diameter/RV ED length and RV function including RV peak systolic strain rate (SR) were measured. We calculated parameters combining load and function (load corrected SR (LcSR): maximal TR gradient (mTRG)/SR), morphology and function (remodelling corrected SR (RcSR): RVRI/SR) or load, morphology and function (load and remodelling corrected SR (LRcSR): mTRG/RVRI/SR) and compared them to 1 year and 5 years mortality Median of follow-up was 3 years. Mortality at 1 year was 17,3% and 22,7% at 5 years. There was no difference of RV morphologic parameters according to 1 year and 5 years mortality. Among classical RV function parameters, only S (11.4 ± 4.4 vs. 8.42 ± 1.7 at 1 yr P = 0.041; 11.4 ± 4.5 vs. 9.2 ± 2.5 at 5 yrs P = 0.020) and SR (1.6 ± 0.8 vs. 1 ± 0.3 at 1 yr P = 0.023; 1.6 ± 0.8 vs. 1.1 ± 0.3 at 5 yrs P = 0.025) were significantly different between alive and dead patients at 1 year and 5 years. All 3 combined parameters were significantly different according to 1 year (LcSR: 14.9 ± 6.2 vs. 20 ± 12.8 P = 0.001; RcSR: 40.8 ± 19.6 vs. 64.7 ± 32.8 P = 0.003; LRcSR: 7.9 ± 3.7 vs. 14.5 ± 7.3 P = 0.027) and 5 years mortality (LcSR: 14.8 ± 6.3 vs. 23.8 ± 11.8 P = 0.001; RcSR: 40.9 ± 19.9 vs. 60.2 ± 31.8 P = 0.012; LRcSR: 7.9 ± 3.8 vs. 13.5 ± 6.9 P = 0.001). By multivariate analysis, combined parameters were the only predictors of 1 year and 5 years mortality. Echography may help prognostic assessment of tricuspid valvular surgery. Combined parameters taking into account RV load, remodelling and function are the most important predictive factors.

Urgent neonatal balloon atrial septostomy in simple transposition of the great arteries: predictive value of fetal cardiac parameters

To investigate the impact of abnormal perinatal loading conditions on cardiac geometry and function in term fetuses and neonates with transposition of the great arteries with intact interventricular septum (simple TGA), and to explore the predictive value of fetal cardiac parameters for an urgent balloon atrial septostomy (BAS) after birth. This was a prospective longitudinal follow-up study of women delivering at term, including both uncomplicated pregnancies with normal outcome and pregnancies affected by fetal simple TGA. Conventional, spectral-tissue Doppler and speckle-tracking echocardiographic parameters were obtained within 1 week before delivery and within the first few hours after delivery. Neonates with simple TGA that required urgent BAS were assessed after the procedure and before corrective arterial switch surgery. Cardiac parameters were normalized by cardiac cycle length, ventricular end-diastolic length or end-diastolic dimension, as appropriate. Fetal and neonatal cardiac parameters were compared between simple-TGA cases and controls, and perinatal changes in the simple-TGA group were assessed. Receiver-operating-characteristics (ROC)-curve analysis was used to assess the predictive value of fetal cardiac parameters for urgent BAS after birth in the simple-TGA group. A total of 67 pregnant women delivering at term were included in the study (54 normal pregnancies and 13 with a diagnosis of fetal simple TGA). Compared with normal term fetuses, term fetuses with simple TGA exhibited more globular hypertrophied ventricles, increased biventricular systolic function and diastolic dysfunction (right ventricular (RV) sphericity index (SI), 0.58 vs 0.54; left ventricular (LV)-SI, 0.55 vs 0.49; combined cardiac output (CCO), 483 vs 406 mL/min/kg; LV torsion, 4.3 vs 3.0 deg/cm; RV isovolumetric relaxation time (IVRT'), 127 vs 102 ms; P < 0.01 for all). Compared with normal neonates, neonates with simple TGA demonstrated biventricular hypertrophy, a more spherical right ventricle and altered systolic and diastolic functional parameters (RV-SI, 0.61 vs 0.43; RV myocardial performance index, 0.47 vs 0.34; CCO, 697 vs 486 mL/min/kg; LV-IVRT', 100 vs 79 ms; RV-IVRT', 106 vs 71 ms; P < 0.001 for all). Paired comparison of neonatal and fetal cardiac indices in the simple-TGA group showed persistence of the fetal phenotype, increased biventricular systolic myocardial contractility and CCO, and diastolic dysfunction (RV systolic myocardial velocity (S'), 0.31 vs 0.24 cm/s; LV-S', 0.23 vs 0.18 cm/s; CCO, 697 vs 483 mL/min/kg; LV torsion, 1.1 vs 4.3 deg/cm; P < 0.001 for all). Several fetal cardiac parameters in term fetuses with simple TGA demonstrated high predictive value for an urgent BAS procedure after birth. Our proposed novel fetal cardiac index, LV rotation-to-shortening ratio, as a potential marker of subendocardial dysfunction, for a cut-off value of ≥ 0.23, had an area under the ROC curve (AUC) of 0.94, sensitivity of 100% and specificity of 83%. For RV/LV end-diastolic area ratio ≥ 1.33, pulmonary-valve-to-aortic-valve-dimension ratio ≤ 0.89, RV/LV cardiac output ratio ≥ 1.38 and foramen-ovale-dimension-to-total-interatrial-septal-length ratio ≤ 0.27, AUC was 0.93-0.98, sensitivity was 86% and specificity was 83-100% for all. Simple-TGA fetuses exhibited cardiac remodeling at term with more profound alterations in these cardiac parameters after birth, suggestive of adaptation to abnormal loading conditions and possible adaptive responses to hypoxemia. Perinatal adaptation in simple TGA might reflect persistence of the abnormal parallel arrangement of cardiovascular circulation and the presence of widely patent fetal shunts imposing volume load on the neonatal heart. The fetal cardiac parameters that showed high predictive value for urgent BAS after birth might reflect the impact of late-gestation pathophysiology and progressive hypoxemia on fetal cardiac geometry and function in simple TGA. If these findings are validated in larger prospective studies, detailed cardiac assessment of fetuses with simple TGA near term could facilitate improvements in perinatal management and refinement of the timing of postnatal intervention strategies to prevent adverse pregnancy outcomes. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

The Preterm Heart-Brain Axis in Young Adulthood: The Impact of Birth History and Modifiable Risk Factors.

People born preterm are at risk of developing both cardiac and brain abnormalities. We aimed to investigate whether cardiovascular physiology may directly affect brain structure in young adulthood and whether cardiac changes are associated with modifiable biomarkers. Forty-eight people born preterm, followed since birth, underwent cardiac MRI at age 25.1 ± 1.4 years and brain MRI at age 33.4 ± 1.0 years. Term born controls were recruited at both time points for comparison. Cardiac left and right ventricular stroke volume, left and right ventricular end diastolic volume and right ventricular ejection fraction were significantly different between preterm and term born controls and associated with subcortical brain volumes and fractional anisotropy in the corpus callosum in the preterm group. This suggests that cardiovascular abnormalities in young adults born preterm are associated with potentially adverse future brain health. Associations between left ventricular stroke volume indexed to body surface area and right putamen volumes, as well as left ventricular end diastolic length and left thalamus volumes, remained significant when adjusting for early life factors related to prematurity. Although no significant associations were found between modifiable biomarkers and cardiac physiology, this highlights that cardiovascular health interventions may also be important for brain health in preterm born adults.

Evaluation of Fetal Cardiac Size and Shape: A New Screening Tool to Identify Fetuses at Risk for Tetralogy of Fallot.

Prenatal detection rates for tetralogy of Fallot (TOF) vary between 23 and 85.7%, in part because of the absence of significant structural abnormalities of the 4-chamber view (4CV), as well as the relative difficulty in detection of abnormalities during the screening examination of the outflow tracts. The purpose of this study was to evaluate whether the 4CV and ventricles in fetuses with TOF may be characterized by abnormalities of size and shape of these structures. This study retrospectively evaluated 44 fetuses with the postnatal diagnosis of TOF. Measurements were made from the 4CV (end-diastolic length, width, area, global sphericity index, and cardiac axis) and the right (RV) and left (LV) ventricles (area, length, 24-segment transverse widths, sphericity index, and RV/LV ratios). Logistic regression analysis was performed to identify variables that might separate fetuses with TOF from normal controls. The mean gestational age at the time of the last examination prior to delivery was 28 weeks 5 days (SD 4 weeks, 4 days). The mean z-scores were significantly lower in fetuses with TOF for the 4CV and RV and LV measurements of size and shape. Logistic regression analysis identified simple linear measurements of the 4CV, RV, and LV that had a sensitivity of 90.9 and specificity of 98.5% that outperformed the 4CV cardiac axis (sensitivity of 22.7%) as a screening tool for TOF. Measurements of the 4CV, RV, and LV can be used as an adjunct to the outflow tract screening examination to identify fetuses with TOF.

Changes in left ventricular size, geometry, pump function and left heart pressures during healthy aging.

There are cross-sectional and longitudinal imaging studies using echocardiography and cardiac magnetic resonance in healthy adult subjects which have demonstrated associations of left ventricular (LV) structure and pump function with age. There are also cross-sectional data regarding the relationships of age with invasively measured left heart chamber pressures. Increasing age is associated with decreases in LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), end-diastolic length (LVEDL), stroke volume (SV) and cardiac output (CO), and increases in relative wall thickness (RWT), LV mass/LVEDV ratio (LVMVR) and ejection fraction (LVEF). Older age is not accompanied by a change in mean left atrial (LA) pressure, but there is both direct and indirect evidence which suggests that LV end-diastolic pressure (LVEDP) increases with age. LVEDV remains lower in older than younger subjects during fluid infusion and the resulting increases in LA pressure. The combination of an increase in LVEF with reductions of both SV and CO demonstrates an age-related increase in divergence between LVEF and LV pump function. A lower LVEDV in older compared to younger subjects can be characterized as an aging-related decrease in LV capacity, with the higher LVEDP in older subjects also indicating a reduction of preload reserve.

Abstract 14546: Left Ventricular Sphericity Index as a Predictor of Appropriate Implantable Cardioverter-defibrillator Therapy

Introduction: We assessed the hypothesis that markers of LV wall stress, such as LV sphericity index (SI), may predict appropriate therapy for ventricular arrhythmias (VA) in patients with primary prevention defibrillators, independent of LV ejection fraction. Methods: We performed a retrospective analysis of consecutive patients with new ICD or CRT-D placement for primary prevention at a single hospital from 01/01/2015 to 06/30/2018. TTE images were used for calculating LV SI, which was defined as the ratio of bi-plane LV end-diastolic volume to the volume of a hypothetical sphere with a diameter of LV end-diastolic length in apical 4-chamber view. Device interrogations were reviewed for appropriate therapy for VA and inappropriate therapy for non-VAs. Kaplan-Meier curves stratified by LV SI tertile were constructed, and Cox proportional hazards models were used to evaluate time to appropriate and inappropriate therapy, and all-cause mortality. Results: A total of 282 patients (ICD 154, CRT-D 128) were included. Baseline characteristics are described in the Table. We found a trend towards increased appropriate therapy as LV SI increased in the ICD but not the CRT-D group, but this was non-significant in both (ICD log-rank 0.63, p-value 0.73; CRT-D log-rank 0.07, p-value 0.96). There was no correlation between LV SI and time to all-cause mortality in the ICD (log-rank 0.53, p-value 0.76) or the CRT-D patients (log-rank 0.51, p-value 0.77). LV SI correlated significantly with time to inappropriate therapy in the ICD (log-rank 8.6, p-value 0.01), but not the CRT-D patients (log-rank 2.4, p-value 0.3). Conclusions: LV SI demonstrated a non-significant trend towards increased appropriate device therapy in the ICD but not the CRT-D group. LV SI predicted inappropriate therapy in the ICD but not the CRT-D group. Study power was limited by lower than expected event rates, possibly due to changes in device programming and improvements in heart failure therapies over time.

Echocardiographic evaluation of monocrotaline induced pulmonary arterial hypertension in rats

Objective To analyze the correlation between the direct measurement of pulmonary artery pressure and the related echocardiographic parameters in rats with pulmonary arterial hypertension (PAH), and establish a predictable equation for pulmonary artery pressure using non-invasive ultrasonic parameters. Methods Fifteen male Wistar rats were randomly divided into normal control (NC) group with five rats and PAH model group with 10 rats.PAH model was established by intraperitoneal injection of 1% MCT solution in the dose of 60 mg/kg. All the rats were examined by ultrasonic apparatus to record cardiac parameters including right ventricle anterior wall thickness (RVAWT), pulmonary artery diameter (PAD), aorta diameter (AOD), pulmonary artery acceleration time (PAAT), pulmonary artery ejection time (PAET), right ventricle end-diastolic diameter (RVEDD), right ventricle end-diastolic length (RVEDL), tricuspid annular plane systolic excursion (TAPSE) and left ventricular ejection fraction(LVEF) before experiments as well as 2 and 4 weeks after modeling. At the fifth week of modeling, all the rats were administrated with thoracotomy and right ventricular catheter to obtain pulmonary artery systolic, diastolic and mean pressures (PASP, PADP and PAMP). Results As time went on, measures of RVAWT, PAD, PAD/AOD, RVEDD, RVEDL, RVEDD/RVEDL increased, while measurements of PAAT, PAAT/PAET, TAPSE decreased in the model group.The changes of RVAWT, PAD, PAAT/PAET, RVEDD in the model group appeared early in the second week in contrast to data before molding (P<0.05). When comparing model group with NC group, there were statistic differences of RVAWT, PAAT/PAET as early as 2 weeks after modeling measuring (all P<0.05) and the dramatic variance in the parameters of PAD/AOD, PAAT, RVEDD, RVEDD/RVEDL, TAPSE appeared in 4-week observation. Correlation analysis suggested there were high-degree correlations between PAAT, PAAT/PAET and PASP, PAMP (for PASP: r=-0.829, -0.865, P<0.05; for PAMP: r=-0.831, -0.842, P<0.05), and moderate-degree correlations between RVAWT, PAD/AOD, RVEDD, RVEDD/RVEDL, TAPSE and PASP, PAMP (for PASP: |r|=0.615-0.786, P<0.05; for PAMP: r=0.683-0.799, P<0.05). The linear dependent equations were established as PASP=-169.392PAAT/PAET+ 105.092 (r2=0.748, P=0.000), PASP=49.576RVAWT+ 67.314RVEDD/RVEDL-45.198 (r2=0.731, P=0.003), PAMP=-150.664PAAT/PAET+ 88.156 (r2=0.709, P=0.001), PAMP=37.988RVAWT+ 82.072RVEDD/RVEDL-50.517 (r2=0.794, P=0.001) to represent the relationships between PASP or PAMP and PAAT/PAET or RVAWTcombined RVEDD/RVEDL. Conclusions Echocardiography can monitor changes in heart structure and hemodynamics.Ultrasonic parameters especially PAAT/PAET or RVAWT, RVEDD/RVEDL could be used to estimate PASP or PAMP measured by catheterization. Key words: Echocardiography; Hypertension, pulmonary; Monocrotaline; Rat

Aging and the relationships between long-axis systolic and early diastolic excursion, isovolumic relaxation time and left ventricular length-Implications for the interpretation of aging effects on e`.

BackgroundBoth the left ventricular (LV) long-axis peak early diastolic lengthening velocity (e`) and long-axis early diastolic excursion (EDExc) decrease with age, but the mechanisms underlying these decreases are not fully understood. The aim of this study was to investigate the relative contributions to aging-related decreases in e`and EDExc from LV long-axis systolic excursion (SExc), isovolumic relaxation time (IVRT, as a measure of the speed of relaxation) and LV end-diastolic length (LVEDL).MethodsThe study group was 50 healthy adult subjects of ages 17–75 years with a normal LV ejection fraction. SExc, EDExc, e`and IVRT were measured from pulsed wave tissue Doppler signals acquired from the septal and lateral walls. Multivariate modelling was performed to identify independent predictors of EDExc and e`which were consistent for the septal and lateral walls.ResultsEDExc decreased with age and the major determinant of EDExc was SExc, which also decreased with age. There was also a decrease of e`with age, and the major determinant of e`was EDExc. IVRT decreased with age and on univariate analysis was not only inversely correlated with EDExc and e`, but also with SExc. IVRT was only a minor contributor to models of EDExc which included SExc, and was an inconsistent contributor to models of e`which included EDExc. LVEDL decreased with age independent of sex and body size, and was positively correlated with SExc, EDExc and e`.ConclusionMajor mechanisms underlying the decrease in e`seen during aging are the concomitant decreases in long-axis contraction and early diastolic excursion, which are in turn related in part to long-axis remodelling of the left ventricle. After adjusting for the extent of systolic and early diastolic excursion, slowing of relaxation, as reflected in prolongation of the IVRT, makes no more than a minor contribution to aging-related decreases in EDExc and e`.

Speckle Tracking of the Basal Lateral and Septal Wall Annular Plane Systolic Excursion of the Right and Left Ventricles of the Fetal Heart.

Annular plane systolic excursion (APSE) has been evaluated for the right (RV) and left (LV) ventricles using M-mode echocardiography. This study examined APSE using 2-dimensional speckle tracking (2DST) of the lateral and septal annuli of the RV and LV in normal fetuses. Two hundred normal fetuses were prospectively examined between 20 and 40 weeks' gestation, in which the end-diastolic and end-systolic lengths were measured from the apex to the insertion of the annuli into the lateral and septal walls of the RV and LV using 2DST. Subtracting the end-systolic from the end-diastolic length resulted in the APSE measurement. The APSE values from the ventricular and septal locations were regressed against biometric and gestational age independent variables, and the mean and standard deviation computed using fractional polynomial analysis. Within-subject repeated measures of variance were used to compare results within and between the right ventricular and left ventricular basal APSE values. When regressed against the independent variables the R2 for the APSE of the right ventricular lateral wall ranged from 0.39 to 0.40, the left ventricular lateral wall 0.29 to 0.31, the right ventricular septal wall 0.22 to 0.40, and the left ventricular septal wall 0.05 to 0.07. There was a significant difference (P < .001) for APSE between the right ventricular and left ventricular lateral wall and their respective septal annuli, the left ventricular and right ventricular lateral wall annuli, and the left ventricular and right ventricular septal annuli. The right ventricular and left ventricular lateral and septal wall APSE can be computed using 2DST and are associated with changing fetal biometric and age measurements.

Abstract 440: The Cardiomyocyte Diastolic Stiffness and Contractility are Inversely Related to the Size of Titin: A Cellular Work Loop Study of Single Intact Cardiomyocytes

Studying cardiac titin under physiological conditions can be at the level of the left ventricular (LV) chamber and the multicellular muscle level. However, those preparations are influenced by neurohormonal reflex, preload-afterload status and extracellular matrix. In this study, cellular work loop force measurement of the single intact cardiomyocyte was conducted under physiological conditions. Intact cell experiments were performed at 37°C under field-stimulation at 2 Hz frequency. The cell was attached to the force transducer and the piezo length controller which modulates the cell length by the feedback control system based on developed force. The force length relation (cellular work loop) of the single cell was generated. The end diastolic force length relation (EDFLR), the end systolic force length relation (ESFLR) and the preload recruitable stroke work (PRSW) were obtained. The Ttn ΔIAjxn -/- ( IA -/- ) mice, in which the I-band/A-band region of titin’s spring has been deleted were studied in comparison to α-MHC-Cre ; cRbm20 ΔRRM +/- ( cRbm20 +/- ) mice which are deficient in titin splicing and express large titin isoforms in the heart. The cellular diastolic stiffness (slope of EDFLR) was increased in IA -/- and was reduced in cRbm20 +/- (151.3, 104.0 and 91.5 μN/mm 2 in IA -/- , WT and cRbm20 +/- respectively). The contractility (slopes of ESFLR and PRSW) were 233.5 and 1215.6 uN/mm 2 in WT, and were increased in IA -/- (371.2 and 2076 μN/mm 2 ) but attenuated in cRbm20 +/- (202.9 and 907.7 μN/mm 2 ). Cellular work loop studies were also conducted in intact cells isolated from the mice that underwent transverse aortic constriction (TAC) surgery with deoxycorticosterone acetate (DOCA) implantation. TAC DOCA mice developed diastolic dysfunction at the LV chamber level. The result showed that the cells from TAC DOCA hearts had increased slopes of EDFLR, ESFLR and PRSW ( 157.9, 378.9 and 1699.0 μN/mm 2 ) compared to the cells from sham mice (98.6, 230.3, and 1203.9 μN/mm 2 ). Conclusions: Cellular work loops recapitulated the cardiac physiology at the LV chamber level. The result showed that the cellular diastolic stiffness and contractility were inversely related to the size of titin and that titin stiffness plays an important roles in both diastolic and systolic function.

The cardiac magnetic resonance sphericity index in the dilated cardiomyopathy: New diagnostic and prognostic marker

Cardiac magnetic resonance (CMR) plays an increasingly important role in the exploration and management of heart failure. The purpose of this study is to assess the diagnostic and prognostic value of left ventricular sphericity in dilated cardiomyopathy. We conducted a retrospective study including 132 patients: 44 diagnosed with dilated cardiomyopathy (DCM+ group) and 88 control patients with normal ventricular function and volumes (DCM− group). All patients underwent a cardiac CMR with standardized clinical protocol: cine-acquisition in short axis, 4-chamber and long axis views and late enhancement data sets acquired 10 minutes after intravenous administration of extracellular gadolinium contrast agent. We determined the sphericity index (SI) = left ventricular short axis end-diastolic length/long axis end-diastolic length × 100. We calculated the sensitivity and specificity of SI as a diagnostic tool of dilated cardiomyopathy and determined its relation to occurrence of cardiac events defined as hospitalization or arrhythmia occurrence or death. In our study SI was inversely correlated with LVEF ( P < 0.001), and positively correlated with end-systolic LV volume ( P = 0.03). The mean SI in the DCM + group was 72.2 ± 7%. An SI ≤ 63.5% had a sensitivity = 90.9% and specificity = 92% in the prediction of dilated cardiomyopathy. Occurrence of a cardiac event was noted in 45% of patients and it was correlated to a high SI ( P < 0.001). Few studies have investigated the SI by CMR. Our study noted that SI was a good diagnostic marker reflecting cardiac dysfunction and prognostic predictor cardiac events occurrence.

Twenty-four Segment Transverse Ventricular Fractional Shortening: A New Technique to Evaluate Fetal Cardiac Function.

Because of various fetal and maternal disease states, this study was conducted to evaluate the fractional shortening of 24 transverse segments distributed from the base to the apex of the ventricular chambers. Two hundred control fetuses were examined between 20 and 40 weeks' gestation. The transverse displacement of the ventricular endocardium during the cardiac cycle was computed by using offline software. From the output of the analysis, 24 end-diastolic and end-systolic segments were measured from the base (segment 1) to the apex (segment 24) of the right and left ventricles, and the fractional shortening was computed: [(end-diastolic length - end-systolic length)/end-diastolic length] × 100. Examples of fetal cardiovascular abnormalities were selected to demonstrate the utility of this technique. The fractional shortening for each segment was independent of gestational age and fetal biometric measurements. There was no significant difference in fractional shortening for segments 1 to 5 between the right and left ventricles. However, the fractional shortening of the left ventricle was significantly greater (P < .0001) than that of the right ventricle for segments 6 to 24, suggesting that the mid and apical segments of the left ventricle have increased displacement toward the center of the chamber compared to the right ventricle. Fetuses with various cardiac structural abnormalities had abnormal fractional shortening values. The fractional shortening of 24 segments of the right and left ventricles provides a comprehensive method to examine the contractility of the ventricular chambers.

P08.04: The relationship between cardiomegaly and global strain in fetuses with intrauterine growth restriction (IUGR)

During the screening examination of the fetal heart cardiomegaly can be identified by computing the area of the 4-chamber view (4CV). The purpose of this study was to compare the relationship between cardiomegaly of the 4CV and global strain of the right (RV) and left (LV) ventricles. 30 fetuses with growth restriction (EFW < 10th centile) were evaluated between 25 and 37 weeks of gestation. The 4CV was identified at end-diastole and the longest basal-apical and transverse lengths were measured, followed by computation of the area. Using previously published criteria, cardiomegaly was defined as an area >90% for the estimated fetal weight (EFW). Global strain was computed using speckle tracking software in which the endocardial length was measured at end-diastole and end-systole from the RV and LV. From these measurements the global strain was computed as follows: [(end-systolic length-end-diastolic length)/end diastolic length) x 100] . Abnormal global strain was defined as values >90th centile derived from Z score computation using data from 200 control fetuses. The mean global strain for the RV was -23 (3.9) and the LV -23 (3.7). Cardiomegaly was present in 46% (14/30) of fetuses with IUGR. Fifty percent of fetuses with cardiomegaly (7/14) had abnormal global strain of the LV, and 64% (9/14) had abnormal global strain of the RV. Abnormal global strain of either the right and/or left ventricles was present in 71% (10/14). A simple method to detect cardiomegaly is to compute the area of the 4CV. If abnormally increased in size, evaluation of global strain of the RV and LV should be considered as it reflects early ventricular dysfunction. While global strain was computed in this study using speckle-tracking software, the end-diastolic and end-systolic endocardial lengths of the ventricular chambers can be measured using generic length measurement software present on most ultrasound machines. From these measurements the global strain can be computed.