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The principal aim of this study was to evaluate changes in systolic function in the single right ventricle (SRV), during progression of the same patient through the three stages of surgical repair for hypoplastic left heart syndrome and during a 5-year follow-up. We hypothesize that, SRV global longitudinal strain (GLS) will be low during 3 stages of repair even in stable patients. We retrospectively evaluated 140 echocardiograms in 20 patients with HLHS (ages 0-11.3 years), before and after 3 stages of surgical palliation. Five-year follow-up data were available in all 20 patients. Controls with structurally normal hearts and in the same age group were used for comparison. We utilized speckle-tracking imaging for assessment of SRV segmental and global longitudinal and circumferential strains, from previously acquired 4-chamber and mid-cavity short-axis views prior to and within 1-3 months of each surgical stage. Longitudinal strain (LS) remained low through all 3 stages of repair and during follow-up. The pre-Fontan stage demonstrated significant interstage improvement compared to the post-Glenn stage despite similar volume status. Global LS was (- 15.6 ± 4.5% after Fontan surgery and remained similar (- 15.32 ± 3.2%) 5 years later. The SRV also showed increased dominance of circumferential strain compared to the normal RV, where the longitudinal deformation was dominant. In SRV, longitudinal strain may be a useful clinical index for evaluating both segmental and global function in an objective manner. Due to lack of significant clinical deterioration over a 10-year period, we speculate that a "lower-than-normal" longitudinal strain may be used as an objective measure of SRV function in clinically stable patients, particularly after the Fontan operation. Compensatory mechanisms where the longitudinal pattern of contraction switches to a more circumferential pattern, may play a role in asymptomatic patients with HLHS.

Although elevated right ventricular pressure and left ventricular diastolic dysfunction measured by echocardiogram are independent predictors of death in adults with sickle cell disease (SCD), the utility of routine echocardiographic screening in the pediatric population is controversial. We performed a 3-year retrospective review of children ≥ 10 years of age with SCD who underwent an outpatient transthoracic echocardiogram as part of a screening program. Of 172 patients referred for screening, 105 (61%) had a measurable tricuspid regurgitation jet velocity (TRV): median 2.4 m/s (IQR 2.3-2.5). Elevated right ventricular (RV) pressure (TRV ≥ 2.5 m/s, 25 mmHg), documented in 30% (32/105), was significantly associated with chronic transfusion therapy and elevated lactate dehydrogenase. Left ventricle (LV) dilation, documented in 25% (44/172), was significantly associated with lower hemoglobin, and higher reticulocyte count, lactate dehydrogenase level, and bilirubin level. There was no association between elevated right ventricular pressure or left ventricle dilation and indices of biventricular systolic or diastolic function. The one death in the cohort during the study period had normal echocardiographic findings. In conclusion, mild RV pressure elevation and LV dilation in children with SCD is associated with abnormal laboratory markers of disease severity, but not with ventricular dysfunction over the 3-year study period.

Background: Studies suggest that right ventricular (RV) fibrosis is associated with RV remodeling and long-term outcomes in patients with tetralogy of Fallot (TOF). Pre-operative hypoxia may increase expression of hypoxia inducible factor-1-alpha (HIF1α) and promote transforming growth factor β1 (TGFβ1)-mediated fibrosis. We hypothesized that there would be associations between: (1) RV fibrosis and RV function, (2) HIF1α variants and RV fibrosis, and (3) HIF1α variants and RV function among post-surgical TOF cases., Methods: We retrospectively measured post-surgical fibrotic load (indexed volume and fibrotic score) from 237 TOF cases who had existing cardiovascular magnetic resonance imaging using late gadolinium enhancement (LGE), and indicators of RV remodeling (i.e., ejection fraction [RVEF] and end-diastolic volume indexed [RVEDVI]). Genetic data were available in 125 cases. Analyses were conducted using multivariable linear mixed-effects regression with a random intercept and multivariable generalized Poisson regression with a random intercept., Results: Indexed fibrotic volume and fibrotic score significantly decreased RVEF by 1.6% (p = 0.04) and 0.9% (p = 0.03), respectively. Indexed fibrotic volume and score were not associated with RVEDVI. After adjusting for multiple comparisons, 6 of the 48 HIF1α polymorphisms (representing two unique signals) were associated with fibrotic score. None of the HIF1α polymorphisms were associated with indexed fibrotic volume, RVEDVI, or RVEF., Conclusion: The association of some HIF1α polymorphisms and fibrotic score suggests that HIF1α may modulate the fibrotic response in TOF.

Background: Echocardiographic follow-up after pediatric heart transplantation is important because of the lifelong risk for rejection and resultant ventricular dysfunction. Although adult studies have shown that echocardiographic measures of right ventricular function are changed after transplantation, similar results have not been reported in the pediatric population., Methods: A single-center retrospective study of echocardiograms obtained among pediatric heart transplant recipients was conducted. All echocardiograms were selected remote from transplantation, rejection, or graft vasculopathy. These criteria identified 127 patients. Right ventricular systolic function was measured using tricuspid annular plane systolic excursion, fractional area change (FAC), and peak systolic tricuspid annular tissue velocity (S'). Results were compared with those in 380 healthy age-matched echocardiographic control subjects., Results: Tricuspid annular plane systolic excursion values in pediatric heart transplant recipients were significantly lower than in control subjects at all ages (P < .0001), with a mean Z score of -3.38. FAC and S' did not vary by age in control patients >6 months of age. FAC values in transplantation patients were significantly decreased compared with those in control subjects (P < .0001), but 83% of transplantation patients had FAC values within the control-derived normal range. S' values were also significantly lower in transplantation patients than control subjects (P < .0001)., Conclusions: Heart transplantation patients have significantly decreased quantitative metrics of right ventricular function relative to healthy control subjects; longitudinal shortening (tricuspid annular plane systolic excursion and S') is particularly affected. FAC is relatively preserved and may be a better metric in this population. These results establish nomograms of RV function in pediatric heart transplantation patients and in normal pediatric control subjects, which may allow quantification of changes in this vulnerable population., (Copyright © 2019 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background Heart size and function in children with single right ventricle (RV) anomalies may be influenced by shunt type at the Norwood procedure. We sought to identify shunt-related differences during early childhood after staged surgical palliations using echocardiography. Methods We compared echocardiographic indices of RV, neoaortic, and tricuspid valve size and function at 14 months, pre-Fontan, and 6 years in 241 subjects randomized to a Norwood procedure using either the modified Blalock-Taussig shunt or RV-to-pulmonary-artery shunt. Results At 6 years, the shunt groups did not differ significantly in any measure except for increased indexed neoaortic area in the modified Blalock-Taussig shunt. RV ejection fraction improved between pre-Fontan and 6 years in the RV-to-pulmonary artery shunt group but was stable in the modified Blalock-Taussig shunt group. For the entire cohort, RV diastolic and systolic size and functional indices were improved at 6 years compared with earlier measurements, and indexed tricuspid and neoaortic annular area decreased from 14 months to 6 years. The prevalence of ≥moderate tricuspid and neoaortic regurgitation was uncommon and did not vary by group or time period. Diminished RV ejection fraction at the 14-month study was predictive of late death/transplant; the hazard of late death/transplant when RV ejection fraction was <40% was tripled (hazard ratio, 3.18; 95% CI, 1.41-7.17). Conclusions By 6 years after staged palliation, shunt type has not impacted RV size and function, and RV and valvar size and function show beneficial remodeling. Poor RV systolic function at 14 months predicts worse late survival independent of the initial shunt type. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT00115934.

Exercise performance is variable and often impaired in patients with repaired tetralogy of Fallot (rTOF). We sought to identify factors associated with exercise performance by comparing high to low performers on cardiopulmonary exercise testing (CPET) in patients with rTOF. We conducted a cross-sectional study of subjects presenting for CPET who underwent echocardiograms at rest and peak exercise. Patients with pacemakers and arrhythmias were excluded. Right ventricular (RV) global longitudinal strain was used as a measure of systolic function. Pulmonary insufficiency (PI) was assessed with the diastolic systolic ratio and the diastolic systolic time-velocity integral ratio by Doppler interrogation of the pulmonary artery. CPET measures included percent-predicted maximum [Formula: see text][Formula: see text], percent-predicted maximum work and oxygen pulse. High versus low performers were identified as those achieving [Formula: see text] of at least 80% or falling below, respectively. Differences in echocardiographic parameters from rest to peak exercise were examined using mixed-effects regression models. Compared to the low performers (n = 17), high performers (n = 12) were younger (12.8 ± 3.3 years vs. 18.3 ± 4.8 years), had normal chronotropic response (peak heart rate > 185 bpm) with greater heart rate reserve and superior physical working capacity. High performers also had a greater reduction in PI at peak exercise, despite greater PI severity at rest. Oxygen pulse was comparable between groups. For both groups, there was no association of PI severity and RV systolic function at rest with exercise parameters. There was no group difference in the magnitude of change in RV strain and diastolic parameters from rest to peak exercise. Chronotropic response to exercise appears to be an important parameter with which to assess exercise performance in rTOF. Chronotropic health should be taken into consideration in this population, particularly given that RV function and PI severity at rest were not associated with exercise performance.

Background: Pulmonary insufficiency (PI) and right ventricular (RV) dysfunction are long-term complications in patients with repaired tetralogy of Fallot (rTOF). The aim of this study was to investigate RV contractile reserve and changes in PI that occur during exercise in patients with rTOF and the associations of these changes with exercise performance using stress echocardiography., Methods: Subjects with rTOF (n = 32) and healthy control subjects (n = 10) were prospectively enrolled and underwent rest and peak exercise echocardiography during standard cardiopulmonary exercise test protocol on a cycle ergometer or treadmill. RV contractile reserve was defined as the change in RV global longitudinal strain from rest to peak exercise. PI was assessed with the diastolic-to-systolic time-velocity integral ratio and diastolic/systolic velocity ratio from pulmonary artery Doppler interrogation. Exercise measures included heart rate reserve, percentage predicted maximum oxygen consumption, percentage predicted maximum work, and oxygen pulse., Results: RV contractile reserve was impaired in patients with rTOF compared with control subjects, with a significant drop in the absolute value of RV global longitudinal strain from 17% (range, 8%-27%) at rest to 13% (range, 5%-28%) at peak exercise. Similarly, PI decreased at peak exercise, with decreases in diastolic-to-systolic time-velocity integral and diastolic/systolic velocity ratios. Reduction in PI was directly associated with percentage predicted maximum oxygen consumption, percentage predicted maximum work, and greater oxygen pulse. Heart rate reserve was directly associated with percentage predicted maximum oxygen consumption and percentage predicted maximum work. RV contractile reserve was not associated with any exercise parameters., Conclusions: Patients with rTOF have an abnormal myocardial response to exercise with impaired RV contractile reserve compared with control subjects. Heart rate reserve and reduction in PI at peak exercise are associated with better exercise performance and appear to be significant contributors to exercise performance in rTOF. Measures to improve chronotropic health in rTOF should be explored., (Copyright © 2018 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background: Right ventricular (RV) dysfunction is associated with adverse long-term outcomes in patients with tetralogy of Fallot. Little is known about RV function in the first years after surgical repair. The aim of this study was to investigate perioperative changes in myocardial deformation using global longitudinal strain., Methods: A retrospective analysis of patients with surgically repaired tetralogy of Fallot was performed. Global longitudinal peak systolic RV strain was measured on early postoperative echocardiograms, two subsequent postoperative echocardiograms through 2 years postoperatively, and preoperative echocardiograms, when available. Preoperative and late follow-up strain was compared with strain in 0- to 8-month-old and 1- to 4-year-old control subjects, respectively., Results: Forty-seven patients were included. Compared with postoperative strain (7 ± 7 days postoperatively), strain at follow-up 1 (8.3 ± 4 months postoperatively) was significantly improved (-12.3 ± 3.3% vs -18.8 ± 2.5%, P < .001), with no additional improvement 23.2 ± 6 months postoperatively (-18.8 ± 2.5% vs -19.8 ± 3.1%, P = .12). Postoperative strain was worse than preoperative strain (n = 25, -12.5 ± 3.6% vs -18.4 ± 2.9%, P < .001). Compared with control subjects, preoperative strain was similar (-19.3 ± 3.8% vs -18.4 ± 2.9%, P = .30), though late follow-up strain was significantly worse (-27.7 ± 2.8% vs -19.8 ± 3.1%, P < .001)., Conclusions: RV global longitudinal strain worsens in the early postoperative period following surgical repair of tetralogy of Fallot but recovers through 2 postoperative years. Despite recovery to preoperative values, the presence of RV dysfunction compared with control subjects suggests that long-term dysfunction may begin early. The trajectory of RV dysfunction through the later years needs further study., (Copyright © 2018 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

IntroductionThe right ventricular adaptations early after surgery in infants with tetralogy of Fallot are important to understand the changes that occur later on in life; this physiology has not been fully delineated. We sought to assess early postoperative right ventricular remodelling in patients with tetralogy of Fallot by cardiac MRI.Materials and methodSubjects with tetralogy of Fallot under 1 year of age were recruited following complete surgical repair for tetralogy of Fallot. Protocol-based cardiac MRI to assess anatomy, function, and flows was performed before hospital discharge using the feed and sleep technique, an unsedated imaging technique., Results: MRI was completed in 16 subjects at a median age of 77 days (interquartile range 114). There was normal ventricular ejection fraction and indexed right ventricular end-diastolic volume (48±13 cc/m2), but elevated right ventricular mass (z score 6.2±2.4). Subjects requiring a transannular patch or right ventricle to pulmonary artery conduit had moderate pulmonary insufficiency (regurgitant fraction 27±16%).DiscussionEarly right ventricular remodelling after surgical repair for tetralogy of Fallot is characterised by significant pulmonary regurgitation, right ventricular hypertrophy, and lack of dilation. Performing cardiac MRI using the feed and sleep technique is feasible in infants younger than 5 months. These results might open new avenues to study longitudinal right ventricular changes in tetralogy of Fallot and to further explore the utility of unsedated MRI in patients with other types of CHDs.

Objective: Tricuspid annular plane systolic excursion (TAPSE) is a reproducible measure of right ventricular systolic function. We sought to determine the reliability of TAPSE measurements, to evaluate TAPSE in patients with hypoplastic left heart syndrome (HLHS) relative to normal values, and to correlate values of TAPSE with measures of exercise performance., Design: Tricuspid annular plane systolic excursion measurements were performed off-line in the cohort of patients with single right ventricle anatomy who had been enrolled in the Sildenafil After Fontan Operation clinical trial. These values were converted to z-scores using age-specific means and standard deviations according to published reference values. Reproducibility of measurements was assessed using the coefficient of variation between two readers. Comparisons between echo measurements and exercise outcomes were assessed using Pearson correlation coefficients., Results: Forty-four echocardiograms from 11 subjects were included in this analysis. The median age of included subjects was 13 years (range 12-17). The coefficient of variation for TAPSE measurements was 5.0%. TAPSE was significantly diminished relative to reference values, with a median z-score of -7.6. TAPSE values correlated with both maximal oxygen consumption (R=.64; P=.033) and oxygen consumption at the anaerobic threshold (R=.73, P=.017)., Conclusions: In this small sample of children with HLHS, TAPSE was reproducible, substantially lower than reference values, and correlated well with measures of exercise performance. Further studies are needed to evaluate these findings in a larger cohort and in a longitudinal manner., Competing Interests: None, (© 2016, Wiley Periodicals, Inc.)

Right ventricular function is a crucial determinant of long-term outcomes of children with heart disease. Quantification of right ventricular systolic and diastolic performance by echocardiography is of paramount importance, given the prevalence of children with heart disease, particularly those with involvement of the right heart, such as single or systemic right ventricles, tetralogy of Fallot, and pulmonary arterial hypertension. Identification of poor right ventricular performance can provide an opportunity to intervene. In this review, we will go through the different systolic and diastolic indices, as well as their application in practice. Quantification of right ventricular function is possible and should be routinely performed using a combination of different measures, taking into account each disease state. Quantification is extremely useful for individual patient follow-up. Laboratories should continue to strive to optimise reproducibility through quality improvement and quality assurance efforts in addition to investing in technology and training for new, promising techniques, such as three-dimensional echocardiography.

Tricuspid annular plane systolic excursion (TAPSE) reflects longitudinal myocardial shortening, the main component of right ventricular (RV) contraction in normal hearts. To date, TAPSE has not been extensively studied in patients with hypoplastic left heart syndrome (HLHS) and systemic RVs after Fontan palliation. This retrospective study investigated HLHS patients after Fontan with cardiac magnetic resonance (CMR) performed between 1 January 2010 and 1 August 2012 and transthoracic echocardiogram (TTE) performed within 6 months of CMR. The maximal apical displacement of the lateral tricuspid valve annulus was measured on CMR (using four-chamber cine images) and on TTE (using two-dimensional apical views). To create TTE-TAPSE z-scores, published reference data were used. Intra- and interobserver variability was tested with analysis of variance. Inter-technique agreement of TTE and CMR was tested with Bland-Altman analysis. In this study, 30 CMRs and TTEs from 29 patients were analyzed. The age at CMR was 14.1 ± 7.1 years, performed 11.9 ± 7.8 years after Fontan. For CMR-TAPSE, the intraclass correlation coefficients for inter- and intraobserver variability were 0.89 and 0.91, respectively. The TAPSE measurements were 0.57 ± 0.2 cm on CMR and 0.70 ± 0.2 cm on TTE (TTE-TAPSE z score, -8.7 ± 1.0). The mean difference in TAPSE between CMR and TTE was -0.13 cm [95 % confidence interval (CI) -0.21 to -0.05], with 95 % limits of agreement (-0.55 to 0.29 cm). The study showed no association between CMR-TAPSE and RVEF (R = 0.08; p = 0.67). In patients with HLHS after Fontan, TAPSE is reproducible on CMR and TTE, with good agreement between the two imaging methods. Diminished TAPSE suggests impaired longitudinal shortening in the systemic RV. However, TAPSE is not a surrogate for RVEF in this study population.

Background: Patients with repaired tetralogy of Fallot are monitored for pulmonary regurgitation (PR) and right ventricular (RV) function. We sought to compare measures of PR and RV function on echocardiogram to those on cardiac magnetic resonance (CMR) and to develop a new tool for assessing PR by echocardiogram., Methods and Results: Patients with repaired tetralogy of Fallot (n=143; 12.5±3.2 years) had an echocardiogram and CMR within 3 months of each other. On echocardiogram, RV function was assessed by (1) Doppler tissue imaging of the RV free wall and (2) myocardial performance index. The ratio of diastolic and systolic time-velocity integrals measured by Doppler of the main pulmonary artery was calculated. CMR variables included RV ejection fraction, RV volumes, and pulmonary regurgitant fraction (RF). Pulmonary regurgitation was graded as mild (RF<20%), moderate (RF=20-40%), and severe (RF>40%). On CMR, RF was 34+17% and RV ejection fraction was 61+8%. Echocardiography had good sensitivity identifying cases with RF>20% (sensitivity 97%; 95% CI: 92-99%) but overestimated the amount of PR when RF<20% (false-positive rate 36%; 95% CI: 18-57%). The diastolic and systolic time-velocity integrals on echocardiogram showed moderate correlation with RF on CMR (R=0.60; P<0.0001). On CMR, RF of 20% and 40% corresponded with a diastolic and systolic time-velocity integral of 0.49 (95% CI: 0.44-0.56) and 0.72 (95% CI: 0.68-0.76), respectively. RV myocardial performance index correlated modestly with RV ejection fraction (r=-0.33; P<0.001)., Conclusions: This study suggests that the diastolic and systolic time-velocity integrals ratio may make a modest contribution to the overall assessment of PR in patients with repaired tetralogy of Fallot and warrants further investigation. However, echocardiography continues to have a limited ability to quantify PR and RV function as compared with CMR.