Normative ranges of biventricular volumes and function in healthy term newborns.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is increasingly used in newborns with congenital heart disease. However, reporting on ventricular volumes and mass is hindered by an absence of normative data in this population. DESIGN/METHODS: Healthy term (37-41 weeks gestation) newborns underwent non-sedated, free-breathing CMR within the first week of life using the 'feed and wrap' technique. End-diastolic volume (EDV), end-systolic volume (ESV) stroke volume (SV) and ejection fraction (EF) were calculated for both left ventricle (LV) and right ventricle (RV). Papillary muscles were separately contoured and included in the myocardial volume. Myocardial mass was calculated by multiplying myocardial volume by 1.05 g/ml. All data were indexed to weight and body surface area (BSA). Inter-observer variability (IOV) was performed on data from 10 randomly chosen infants. RESULTS: Twenty healthy newborns (65% male) with a mean (SD) birth weight of 3.54 (0.46) kg and BSA of 0.23 (0.02) m2 were included. Normative LV parameters were indexed EDV 39.0 (4.1) ml/m2, ESV 14.5 (2.5) ml/m2 and ejection fraction (EF) 63.2 (3.4)%. Normative RV indexed EDV, ESV and EF were 47.4 (4.5) ml/m2, 22.6 (2.9) ml/m2 and 52.5 (3.3)% respectively. Mean LV and RV indexed mass were 26.4 (2.8) g/m2 and 12.5 (2.0) g/m2, respectively. There was no difference in ventricular volumes by gender. IOV was excellent with an intra-class coefficient > 0.95 except for RV mass (0.94). CONCLUSION: This study provides normative data on LV and RV parameters in healthy newborns, providing a novel resource for comparison with newborns with structural and functional heart disease.

Impaired right and left ventricular function and relaxation induced by pulmonary regurgitation are not reversed by tardive antifibrosis treatment.

Pulmonary regurgitation (PR) after repair of tetralogy of Fallot (rTOF) is associated with progressive right (RV) and left (LV) ventricular dysfunction and fibrosis. However, angiotensin II receptor blockade therapy has shown mixed and often disappointing results. The aim of this study was to serially assess changes in biventricular remodeling, dysfunction, and interactions in a rat model of isolated severe PR and to study the effects of angiotensin II receptor blockade. PR was induced in Sprague-Dawley rats by leaflet laceration. Shams (n = 6) were compared with PR (n = 5) and PR + losartan treatment (n = 6). In the treatment group, oral losartan (50 mg·kg-1·day-1) was started 6 wk after PR induction and continued for 6 wk until the terminal experiment. In all groups, serial echocardiography was performed every 2 wk until the terminal experiment where biventricular myocardium was harvested and analyzed for fibrosis. PR and PR + losartan rats experienced early progressive RV dilatation by 2 wk which then stabilized. RV systolic dysfunction occurred from 4 wk after insult and gradually progressed. In PR rats, RV dilatation caused diastolic LV compression and impaired relaxation. PR rats developed increased RV fibrosis compared with shams. Although losartan decreased RV fibrosis, RV dilatation and dysfunction were not improved. This suggests that RV dilatation is an early consequence of PR and affects LV relaxation. RV dysfunction may progress independent of further remodeling. Reduced RV fibrosis was not associated with improved RV function and may not be a viable therapeutic target in rTOF with predominant RV volume loading.NEW & NOTEWORTHY The time-course of RV dilatation and the mechanisms of biventricular dysfunction caused by PR have not been well characterized and the effect of losartan in volume-overloaded RV remains controversial. Our findings suggest that severe PR induces early onset of RV dilatation and dysfunction with little progression after the first 4 wk. The RV dilatation distorts LV geometry with associated impaired LV relaxation. Losartan reduced RV fibrosis but did not reverse RV dilatation and dysfunction.

Comparison of Right Ventricular Function Between Three-Dimensional Transesophageal Echocardiography and Pulmonary Artery Catheter.

OBJECTIVE: This study aimed to compare measurements of right ventricular function using three-dimensional transesophageal echocardiography (3D TEE), and pulmonary artery catheters (PACs) in patients undergoing cardiac surgery. The authors examined the practicality of using the 3D TEE. DESIGN: Prospective observational. SETTING: Cardiac operating room at a single university hospital. PARTICIPANTS: All adult patients undergoing elective cardiac surgery at a single tertiary care university hospital over two years. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), stroke volume (SV), and right ventricular ejection fraction (RVEF) were measured with both 3D TEE and PACs. Assessments were performed using correlation coefficients, paired t tests, and Bland-Altman plots. Thirty-one patients participated in this study. Each measurement showed good agreement. RVEDV and RVESV were slightly lower on 3D TEE than on PAC (205.9 mL v 220.2 mL, p = 0.0018; 143.0 mL v 155.5 mL, p = 0.0143, respectively), whereas no significant differences were observed for SV and RVEF (31.0% v 31.1%, p = 0.0569; 61.6 mL v 66.9 mL, p = 0.92, respectively). Linear regression analysis showed high correlation between 3D TEE and PAC for RVEDV (r = 0.87) and RVESV (r = 0.81), and moderate correlation for SV (r = 0.67) and RVEF (r = 0.67). In the Bland-Altman plot, most patients were within the 95% limits of the agreement throughout all measurements. CONCLUSION: A high correlation was found between measurements made with a PAC and with 3D TEE in the assessment of right ventricular function. Three-dimensional TEE would be a potential alternative to PAC for assessment of right ventricular function during intraoperative periods.

Preoperative Threshold for Normalizing Right Ventricular Volume After Transcatheter Closure of Adult Atrial Septal Defect.

BACKGROUND: The latest guidelines recommend early intervention in adult atrial septal defect (ASD) patients with signs of right ventricular (RV) enlargement. However, the criteria of RV enlargement for optimal intervention remain unclear. We investigated the preoperative determinants for normalizing the RV volume after transcatheter closure of ASD in adults.Methods and Results:We retrospectively analyzed 52 ASD patients who underwent transcatheter closure. Cardiac magnetic resonance imaging (CMR) measured RV volume before and 1 year after the closure. The patients were divided into normalized (postoperative RV end-systolic volume index [RVESVI] <47 mL/m2and end-diastolic volume index [RVEDVI] <108 mL/m2) and non-normalized (postoperative RVESVI ≥47 mL/m2or RVEDVI ≥108 mL/m2) groups. Preoperative RVESVI was significantly smaller (72 mL/m2vs. 80 mL/m2) and RVEF was higher (56% vs. 51%) in the normalized group compared with the non-normalized group. Receiver-operating characteristic analysis for the normalization of postoperative RV volume showed that the preoperative threshold value of RVESVI was 75 mL/m2. In addition, multivariate analysis showed that preoperative RVESVI was an independent predictor for normalization of RV volume. CONCLUSIONS: Preoperative RVESVI is an independent predictor for normalization of RV volume at 1 year after transcatheter closure of ASD in adults. Early intervention before RVESVI reaches 75 mL/m2may confer optimal timing for normalizing RV volume.

Incremental value of three-dimensional transthoracic echocardiography over the two-dimensional modality in the assessment of right heart compression and dysfunction produced by pectus excavatum.

The usefulness of two-dimensional transthoracic echocardiography (2DTTE) in the assessment of right heart compression and dysfunction produced by pectus excavatum chest wall deformity has been well described in the literature by several investigators. However, there is a paucity of reports describing incremental value of live/real time three-dimensional transthoracic echocardiography (3DTTE) over the two-dimensional technique in the evaluation of right heart function in these patients. We present a severe case of pectus excavatum chest wall deformity in a young male, in whom 3DTTE provided incremental value over standard 2DTTE in assessing compression of the right heart before surgery and marked improvement in right heart function parameters following surgical repair. In addition, an updated summary of salient features of this deformity, including 2D and 3DTTE findings as well as right heart echocardiographic parameters by both 2D and 3DTTE in normal/healthy subjects summarized from the literature have been provided in a tabular form for comparison.

Cor triatriatum dexter with right ventricular hypoplasia: Role of multimodality imaging in decision making.

Cor Triatriatum Dexter (CTD) is a rare congenital anomaly involving the systemic venous valves. Failure of regression of the right-sided sinus venosus valve leads to abnormal septation of the right atrium and a variety of right atrial and tricuspid valve obstructive lesions. The presentation can be varied ranging from asymptomatic to persistent neonatal cyanosis. We describe a late diagnosis of CTD in a 10-month-old male with persistent hypoxia despite balloon valvuloplasty for mild pulmonic valve stenosis with a large secundum atrial septal defect and a mildly hypoplastic right ventricle.

Determination of Right Ventricular Volume by Combining Echocardiographic Distance Measurements.

BACKGROUND: The position of the right ventricle (RV), often partly behind the sternum, implies difficulties to image the RV free wall using transthoracic echocardiography (TTE) and consequently limits the possibilities of stroke volume calculations. The aim of this study was to evaluate whether the volume of the right ventricle (RV) can be determined by combining TTE distance measurements that do not need the RV free wall to be fully visualized. METHODS: The RV volume was approximated by an ellipsoid composed of three distances. Distance measurements, modeled RV stroke volumes (RVSV), and RV ejection fraction (RVEF) were compared to reference values obtained from cardiac magnetic resonance (CMR) imaging for 12 healthy volunteers. RESULTS: Inter-modality comparisons showed that distance measurements were significantly underestimated in TTE compared to CMR. The modeled RV volumes using TTE distance measurements were underestimated compared to reference CMR volumes. There was, however, for TTE an agreement between modeled RVSV and left ventricular stroke volumes determined by biplane Simpson's rule. Similar agreement was shown between modeled RVSV based on CMR distance measurements and the CMR reference. Regarding RVEF, further studies including patients with a wider range of RVEF are needed to evaluate the method. CONCLUSION: In conclusion, the ellipsoid model of the RV provides good estimates of RVSVs, but volumes based on distance measurements from different modalities cannot be used interchangeably.

Relationship of Right Ventricular Size and Function with Respiratory Status in Duchenne Muscular Dystrophy.

The relationship between pulmonary function and right ventricle (RV) in Duchenne muscular dystrophy (DMD) has not been evaluated. Using cardiac magnetic resonance (CMR), we describe the relationship of RV size and function with spirometry in a DMD cohort. Fifty-seven boys undergoing CMR and pulmonary function testing within 1 month at a single center (2013-2015) were enrolled. Comparisons of RV ejection fraction (RVEF) and end-diastolic volume index (RVEDVI) were made across categories of percent forced vital capacity (FVC%), and relationships were assessed. Mean age was 15.5 ± 3.5 years. Spirometry and CMR were performed within 3.9 ± 4.1 days. Median FVC% was 92.0 % (67.5-116.5 %). Twenty-three (40 %) patients had abnormal FVC% (<80 %) of which 13 (57 %) had mild (FVC% 60-79 %), 6 (26 %) had moderate (FVC% 40-59 %), and 4 (17 %) had severe (FVC <40 %) reductions. Mean RVEF was 58.3 ± 3.7 %. Patients with abnormal FVC% were older and had lower RVEF and RVEDVI. Both RVEF and RVEDVI were significantly associated with FVC% (r = 0.31, p = 0.02 and r = 0.39, p = 0.003, respectively). In a large DMD cohort, RVEF and RVEDVI were related to FVC%. Worsening respiratory status may guide monitoring of cardiac function in these patients.

Evaluation of the Truncated Cone-Rhomboid Pyramid Formula for Simplified Right Ventricular Quantification: A Cardiac Magnetic Resonance Study.

Background/Objective: Cardiac magnetic resonance (CMR) is the reference method for right ventricular (RV) volume and function analysis, but time-consuming manual segmentation and corrections of imperfect automatic segmentations are needed. This study sought to evaluate the applicability of an echocardiographically established truncated cone-rhomboid pyramid formula (CPF) for simplified RV quantification using CMR. Methods: A total of 70 consecutive patients assigned to RV analysis using CMR were included. As standard method, the manual contouring of RV-short axis planes was performed for the measurement of end-diastolic volume (EDV) and end-systolic volume (ESV). Additionally, two linear measurements in four-chamber views were obtained in systole and diastole: basal diameters at the level of tricuspid valve (Dd and Ds) and baso-apical lengths from the center of tricuspid valve to the RV apex (Ld and Ls) were measured for the calculation of RV-EDV = 1.21 × Dd2 × Ld and RV-ESV = 1.21 × Ds 2 × Ls using CPF. Results: RV volumes using CPF were slightly higher than those using standard CMR analysis (RV-EDV index: 86.2 ± 29.4 mL/m2 and RV-ESV index: 51.5 ± 22.5 mL/m2 vs. RV-EDV index: 81.7 ± 24.1 mL/m2 and RV-ESV index: 44.5 ± 23.2 mL/m2) and RV-EF was lower (RV-EF: 41.1 ± 13.5% vs. 48.4 ± 13.7%). Both methods had a strong correlation of RV volumes (ΔRV-EDV index = -4.5 ± 19.0 mL/m2; r = 0.765, p < 0.0001; ΔRV-ESV index = -7.0 ± 14.4 mL/m2; r = 0.801, p < 0.0001). Conclusions: Calculations of RV volumes and function using CPF assuming the geometrical model of a truncated cone-rhomboid pyramid anatomy of RV is feasible, with a strong correlation to measurements using standard CMR analysis, and only two systolic and diastolic linear measurements in four-chamber views are needed.

Echocardiographic assessment of right ventricular volume in repaired tetralogy of Fallot: a novel approach to an older technique.

BACKGROUND: In repaired tetralogy of Fallot (rTOF), right ventricular (RV) enlargement leads to poor outcomes. However, evaluating the RV has limitations; cardiac magnetic resonance (CMR) and 3D echocardiography have barriers including cost and accessibility. Traditional echocardiography is limited given the complex geometry and anterior location of the RV. We propose a novel echocardiographic evaluation of RV volume using 2 separate views. METHODS: This is a retrospective study of rTOF patients with echocardiogram, CMR, and exercise tests. By echocardiogram, we collected RV length in parasternal long axis (PLAX), area in 4-chamber (4C) view, and measurements per standard guidelines. RV end-diastolic and end-systolic volume (RVEDV and RVESV) were calculated as 5/9 (4C area * PLAX length). RESULTS: Forty-five patients with 66 sets of CMR, echocardiogram, and exercise tests were included (mean age 13.3 ± 3.2 years). The echocardiographic RVEDV and RVESV showed strong correlation with CMR parameters (r = 0.81 and 0.72; p≤ 0.0001), and moderate correlation with peak oxygen pulse (0.63 and 0.49; p≤0.0001). Guideline measurements had no significant correlation. Echocardiographic RVEDV and RVESV were higher in those requiring subsequent pulmonary valve replacement. Indexed echocardiographic RVEDV of 93 ml/m2 had 92% sensitivity and 50% specificity (area under curve 0.75 (p = 0.001)) in predicting CMR RV/LV EDV ratio > 2, which is an early indicator for pulmonary valve replacement. CONCLUSIONS: This novel technique correlates strongly with CMR, better than traditional parameters. While echocardiogram will not replace CMR, this method would be useful in predicting the RV volume, progression of dilation, and timing of CMR.

4D imaging of fetal right ventricle-feasibility study and a review of the literature.

Functional analysis of the fetal cardiovascular system is crucial for the assessment of fetal condition. Evaluation of the right ventricle with standard 2D echocardiography is challenging due to its complex geometry and irregular muscle fibers arrangement. Software package TOMTEC 4D RV-Function is an analysis tool which allows assessment of right ventricular function based on volumetric measurements and myocardial deformation. The aim of this study was to determine the feasibility of this method in fetal echocardiography. The retrospective study was conducted in the high-flow Referral Center for Fetal Cardiology. We recorded 4D echocardiographic sequences of 46 fetuses with normal hearts. Following parameters were calculated: end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF), right ventricle longitudinal free-wall (RVLS free-wall) and septal strain (RVLS septum). Tei index was calculated as a standard measure or RV function for comparison. 4D assessment was feasible in 38 out of 46 fetuses (83%). RV volumetric parameters-EDV, ESV and SV-increased exponentially with gestational age. Functional parameters-RV Tei index, EF and strains-were independent of gestational age. Mean EF was 45.2% (± 6%), RV free-wall strain was - 21.2% and RV septal strain was - 21.5%. There was a statistically significant correlation between septal and free-wall strains (r = 0.51, p = 0.001) as well as between EF and RV free-wall strain (r = - 0.41, p = 0.011). 4D RV assessment is feasible in most fetuses. Its clinical application should be further investigated in larger prospective studies.

Utility of Real-Time Three-Dimensional Echocardiography for the Assessment of Right Ventricular Morphology and Function in Large Animal Models.

Real-time three-dimensional echocardiography (RT3DE) enables a noninvasive assessment of right ventricular (RV) morphology. However, no study has evaluated the relationship between RV function obtained by RT3DE and RV pressure-volume loops. This hypothesis-driven, experimental study aimed to assess the utility of RT3DE in the evaluation of RV morphology and function. Ten anesthetized beagle dogs sequentially underwent dobutamine infusion, acute infusion of lactated Ringer's solution, and furosemide administration to alter RV contractility and loading conditions. RV pressure-volume loop-derived hemodynamic measurements and echocardiography, including two-dimensional speckle-tracking echocardiography and RT3DE, were performed in each study protocol. Bland−Altman analysis showed strong agreement in RV volume, ejection fraction, and stroke volume obtained by right heart catheterization and RT3DE. Multiple regression analyses revealed that the peak myocardial velocity of the lateral tricuspid annulus (RV s') and global RV longitudinal strain rate were significantly associated with end-systolic elastance (adjusted r2 = 0.66, p < 0.001). RV s', RV free wall longitudinal strain, and RT3DE-derived stroke volume/end-systolic RV volume ratio were associated with RV pressure-volume loops-derived end-systolic/arterial elastance ratio (adjusted r2 = 0.34, p < 0.001). RT3DE could detect the changes in catheterization-derived RV volume with a strong agreement and might be useful in estimating RV-pulmonary arterial coupling.

Morphological changes of the tricuspid valve complex in functional tricuspid regurgitation on contrast-enhanced computed tomography.

BACKGROUND: Whether it is possible to perform morphological evaluation of functional tricuspid regurgitation (FTR) on contrast-enhanced computed tomography (CT) was examined by evaluating the relationships between the parameters measured on contrast-enhanced CT and TR severity on transthoracic echocardiography. METHODS: Fifty patients underwent contrast-enhanced CT. Tricuspid annulus area (TAA), tricuspid annulus circumference (TAC), right ventricular volume (RVV), and the distances between the tips and bases of the papillary muscles were measured on contrast-enhanced CT in diastole and systole. The 50 cases were divided into 34 in the TR ≤ mild group (no TR: 3 cases, trivial TR: 24 cases, mild TR: 7 cases), and 16 in the TR ≥ moderate group (moderate TR: 8 cases, severe TR: 8 cases) using the TR grade measured by transthoracic echocardiography, and then differences between the groups were examined. RESULTS: Significant differences were found in TAA, TAC, and RVV (p < 0.01) and the distances between the tips of the anterior and posterior papillary muscles (p < 0.05) in both diastole and systole. Since the septal papillary muscle could not be identified in 18 cases (36.0%), only the distance between the anterior and posterior papillary muscles was measurable in all cases. On receiver-operating characteristic (ROC) curve analysis, the areas under the ROC curves (AUCs) of TAA, TAC, and RVV were all > 0.7, and the maximum AUC was 0.925 for dRVV. CONCLUSIONS: TAA, TAC, RVV, and the distance between the tips of the anterior and posterior papillary muscles measured on contrast-enhanced CT were shown to be significantly increased in the TR ≥ moderate group. Detailed morphological assessment of FTR is possible by contrast-enhanced CT.

Feasibility and Accuracy of a Fully Automated Right Ventricular Quantification Software With Three-Dimensional Echocardiography: Comparison With Cardiac Magnetic Resonance.

Background: A novel, fully automated right ventricular (RV) software for three-dimensional quantification of RV volumes and function was developed. The direct comparison of the software performance with cardiac magnetic resonance (CMR) was limited. Therefore, the aim of this study was to test the feasibility, accuracy, and reproducibility of a fully automated RV quantification software against CMR imaging as a reference. Methods: A total of 170 patients who underwent both CMR and three-dimensional echocardiography were enrolled. RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), and RV ejection fraction (RVEF) were obtained using fully automated three-dimensional RV quantification software and compared with a CMR reference. For inter-technical agreement, Spearman correlation and Bland-Altman analysis were used. Results: The fully automated RV quantification software was feasible in 149 patients. RVEDV and RVESV were underestimated, and RVEF was overestimated compared with CMR values. RV measurements obtained from the manual editing method correlated better with CMR values than that without manual editing (RVEDV, 0.924 vs. 0.794: RVESV, 0.955 vs. 0.854; RVEF, 0.941 vs. 0.781 respectively, all p < 0.0001) with less bias and narrower limit of agreement (LOA). The bias and LOA for RV volumes and EF using the automated software without and with manual editing were greater in patients with severely impaired RV function or low frame rate than those with normal and mild impaired RV function, or high frame rate. The fully automated RV three-dimensional measurements were highly reproducible. Conclusion: The novel fully automated RV software shows good feasibility and reproducibility, and the measurements had a high correlation with CMR values. These findings support the routine application of the novel 3D automated RV software in clinical practice.

Asymmetric Regional Work Contributes to Right Ventricular Fibrosis, Inefficiency, and Dysfunction in Pulmonary Hypertension versus Regurgitation.

BACKGROUND: Right ventricular (RV) pressure loading from pulmonary hypertension (PH) and volume loading from pulmonary regurgitation (PR) lead to RV dysfunction, a critical determinant of clinical outcomes, but their impact on regional RV mechanics and fibrosis is poorly characterized. The aim of this study was to test the hypothesis that regional myocardial mechanics and efficiency in RV pressure and volume loading are associated with RV fibrosis and dysfunction. METHODS: Eight PH, six PR, and five sham-control rats were studied. The PH rat model was induced using Sugen5416, a vascular endothelial growth factor receptor 2 inhibitor, combined with chronic hypoxia. PR rats were established by surgical laceration of the pulmonary valve leaflets. Six (n = 4) or 9 (n = 4) weeks after Sugen5416 and hypoxia and 12 weeks after PR surgery, myocardial strain and RV pressure were measured and RV pressure-strain loops generated. We further studied RV regional mechanics in 11 patients with PH. Regional myocardial work was calculated as the pressure-strain loop area (mm Hg ∙ %). Regional myocardial work efficiency was quantified through wasted work (ratio of systolic lengthening to shortening work). The relation of regional myocardial work to RV fibrosis and dysfunction was analyzed. RESULTS: In rats, PH and PR induced similar RV dilatation, but fractional area change (%) was lower in PH than in PR. RV lateral wall work was asymmetrically higher in PH compared with sham, while septal work was similar to sham. In PR, lateral and septal work were symmetrically higher versus sham. Myocardial wasted work ratio was asymmetrically increased in the PH septum versus sham. Fibrosis in the RV lateral wall, but not septum, was higher in PH than PR. RV fibrosis burden was linearly related to regional work and to measures of RV systolic and diastolic function but not to wasted myocardial work ratio. Patients with PH demonstrated similar asymmetric and inefficient regional myocardial mechanics. CONCLUSIONS: Asymmetric RV work and increased wasted septal work in experimental PH are associated with RV fibrosis and dysfunction. Future investigation should examine whether assessment of asymmetric regional RV work and efficiency can predict clinical RV failure and influence patient management.

Association of Digoxin With Preserved Echocardiographic Indices in the Interstage Period: A Possible Mechanism to Explain Improved Survival?

Background For patients with hypoplastic left heart syndrome, digoxin has been associated with reduced interstage mortality after the Norwood operation, but the mechanism of this benefit remains unclear. Preservation of right ventricular (RV) echocardiographic indices has been associated with better outcomes in hypoplastic left heart syndrome. Therefore, we sought to determine whether digoxin use is associated with preservation of the RV indices in the interstage period. Methods and Results We conducted a retrospective cohort study of prospectively collected data using the public use data set from the Pediatric Heart Network Single Ventricle Reconstruction trial, conducted in 15 North American centers between 2005 and 2008. We included all patients who survived the interstage period and had echocardiographic data post-Norwood and pre-Glenn operations. We used multivariable linear regression to compare changes in RV parameters, adjusting for relevant covariates. Of 289 patients, 94 received digoxin at discharge post-Norwood. There were no significant differences in baseline clinical characteristics or post-Norwood echocardiographic RV indices (RV end-diastolic volume indexed, RV end-systolic volume indexed, ejection fraction) in the digoxin versus no-digoxin groups. At the end of the interstage period and after adjustment for relevant covariates, patients on digoxin had better preserved RV indices compared with those not on digoxin for the ΔRV end-diastolic volume (11 versus 15 mL, P=0.026) and the ΔRV end-systolic volume (6 versus 9 mL, P=0.009) with the indexed ΔRV end-systolic volume (11 versus 20 mL/BSA1.3, P=0.034). The change in the RV ejection fraction during the interstage period between the 2 groups did not meet statistical significance (-2 versus -5, P=0.056); however, the trend continued to be favorable for the digoxin group. Conclusions Digoxin use during the interstage period is associated with better preservation of the RV volume and tricuspid valve measurements leading to less adverse remodeling of the single ventricle. These findings suggest a possible mechanism of action explaining digoxin's survival benefit during the interstage period.

Noninvasive prediction of pulmonary hemodynamics in chronic thromboembolic pulmonary hypertension by electrocardiogram-gated computed tomography.

PURPOSE: The aim of the study was to investigate the potential of electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) as a predictor of disease severity in patients with chronic thromboembolic pulmonary hypertension (CTEPH). METHOD: Forty-five CTEPH patients with a mean age of 63.8 years±12.7 y (±standard deviation) who had undergone ECG-gated CTPA and right heart catheterization (RHC) were included in the study. Right ventricular to left ventricular volume ratio (RVV/LVV), diameter ratio on 4-chamber view (RVD4CH/LVD4CH), pulmonary trunk (PT) diameter, PT to aortic diameter ratio (PT/A), and septal angle were correlated to mean pulmonary artery pressure (mPAP). Moreover, RVV/LVV and RVD4CH/LVD4CH were adjusted to pulmonary diameter index (PADi) and PT/A index. Areas under the curve (AUC) for predicting mPAP above 40 mmHg, 35 mmHg, and 30 mmHg were calculated. RESULTS: RVD4CH/LVD4CH revealed the strongest correlation to mPAP before (r = 0.6507) and after (r = 0.7650; p < 0.0001) PT/A adjustment. The AUCs for predicting pH with mPAP over 40 mmHg and 30 mmHg were 0.9229 and 0.864, respectively. A cutoff value of 1.298 enabled prediction of pH with mPAP over 40 mmHg with a sensitivity, specificity, positive predictive, and negative predictive value of 80.00 %, 95.83 %, 88.46 %, and 94.12 %, respectively. Intra- and interobserver variability were excellent for all parameters. CONCLUSION: Combining different and easily evaluable ECG-gated CTPA parameters enables excellent prediction of pulmonary hemodynamics in CTEPH patients. Ventricular diameter ratio on 4-chamber view adjusted by the PT/A ratio yielded the best correlation to mPAP.

Left ventricular vortex analysis by high-frame rate blood speckle tracking echocardiography in healthy children and in congenital heart disease.

BACKGROUND: High-frame rate blood speckle tracking (BST) echocardiography is a new technique for the assessment of intracardiac flow. The purpose of this study was to evaluate the characteristics of left ventricular (LV) vortices in healthy children and in those with congenital heart disease (CHD). METHODS: Characteristics of LV vortices were analyses based on 4-chamber BST images from 118 healthy children (median age 6.84 years, range 0.01-17 years) and 43 children with CHD (median age 0.99 years, range 0.01-14 years). Both groups were compared after propensity matching. Multiple linear regression was used to identify factors that independently influence vortex characteristics. RESULTS: Feasibility of vortex imaging was 93.7% for healthy children and 95.6% for CHD. After propensity matching, there were no overall significant differences in vortex distance to apex, distance to interventricular septum (IVS), height, width, sphericity index, or area. However, multiple regression analysis revealed significant associations of LV morphology with vortex characteristics. Furthermore, CHD involving LV volume overload and CHD involving LV pressure overload were both associated with vortices localized closer to the IVS. CONCLUSIONS: LV vortex analysis using high-frame rate BST echocardiography is feasible in healthy children and in those with CHD. As they are associated with LV morphology and are modified in some types of CHD, vortices might yield diagnostic and prognostic value. Future studies are warranted to establish applications of vortex imaging in the clinical setting.

Accuracy of fully automated right ventricular quantification software with 3D echocardiography: direct comparison with cardiac magnetic resonance and semi-automated quantification software.

AIMS: The aim of this study was to determine the accuracy and reproducibility of a novel, fully automated 3D echocardiography (3DE) right ventricular (RV) quantification software compared with cardiac magnetic resonance (CMR) and semi-automated 3DE RV quantification software. METHODS AND RESULTS: RV volumes and the RV ejection fraction (RVEF) were measured using a fully automated software (Philips), a semi-automated software (TomTec), and CMR in 100 patients who had undergone both CMR and 3DE examinations on the same day. The feasibility of the fully automated software was 91%. Although the fully automated software, without any manual editing, significantly underestimated RV end-diastolic volume (bias: -12.6 mL, P < 0.001) and stroke volume (-5.1 mL, P < 0.001) compared with CMR, there were good correlations between the two modalities (r = 0.82 and 0.78). No significant differences in RVEF between the fully automated software and CMR were observed, and there was a fair correlation (r = 0.72). The RVEF determined by the semi-automated software was significantly larger than that by CMR or the fully automated software (P < 0.001). The fully automated software had a shorter analysis time compared with the semi-automated software (15 s vs. 120 s, P < 0.001) and had a good reproducibility. CONCLUSION: A novel, fully automated 3DE RV quantification software underestimated RV volumes but successfully approximated RVEF when compared with CMR. No inferiority of this software was observed when compared with the semi-automated software. Rapid analysis and higher reproducibility also support the routine adoption of this method in the daily clinical workflow.