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Individuals with hemoglobinopathy (sickle cell anemia and thalassemia major) are at risk for cardiac complications such as heart failure and cardiomyopathy. Diastolic dysfunction is known to precede systolic dysfunction in many cardiac diseases. This study sought to determine whether changes in left atrial (LA) function during manipulation of cardiac preload by tilt-table echocardiography can unmask subclinical diastolic dysfunction in pediatric patients with hemoglobinopathies. Eleven sickle cell anemia, 9 transfusion-dependent thalassemia major, and 10 control subjects underwent tilt-table echocardiogram in the supine (loading) and 30-degree upright (unloading) positions and cardiac magnetic resonance imaging (MRI). Echocardiography assessed LA and left ventricular (LV) strain, strain rate, mitral inflow, and annular velocities. MRI assessed LV function, myocardial T1 and T2* for iron deposition. Both thalassemia major and sickle cell anemia patients had normal LV function and no evidence of cardiac iron deposition on MRI T2* measurements. During cardiac loading, controls appropriately increased LA conduit (P=0.002) and reservoir strain (P=0.002), mitral e' velocity (P<0.0001) and medial e' velocity (P=0.002), while the hemoglobinopathy patients showed no change in these parameters. In pediatric sickle cell anemia and thalassemia, tilt-table echocardiography unmasked a failure to augment LA function in response to loading, suggesting altered myocardial relaxation is present, before evidence of iron overload or systolic dysfunction.

Background: The aim of this study was to evaluate left ventricular function in preterm infants from 28 days to near term using echocardiography., Methods: Thirty clinically stable preterm infants delivered at <30 weeks' gestational age were prospectively enrolled. At 28 days, conventional, tissue Doppler, and speckle-tracking echocardiography evaluations of left ventricular function were performed, with comparison made to findings in 30 healthy term infants of similar postnatal age. Sixteen preterm infants underwent repeat examinations near term., Results: Compared with controls, preterm infants at 28 days had decreased peak mitral valve (MV) E-wave velocities (P < .01), E/A ratios (P < .0001), annular e' velocities (P < .0001), and e'/a' ratios (P < .0001); increased MV E/e' ratios (P < .01); and lower basal circumferential early diastolic and higher late diastolic strain rates. No significant differences were found in fractional shortening, ejection fraction, and longitudinal or circumferential strain and strain rate between preterm infants and controls. Although preterm infants at 28 days had higher heart rates compared with controls (161 ± 15 vs 142 ± 16 beats/min), no significant correlations existed between heart rate and MV E, E/A ratio, e', e'/a' ratio, and E/e' ratio. Near term, the differences in diastolic function persisted, including decreased MV e'/a' ratio (P < .05), increased E/e' ratio (P < .01), and increased late diastolic strain rate., Conclusions: Clinically stable preterm infants have normal left ventricular systolic function but altered diastolic function, with greater dependence on atrial contraction, the latter of which persists despite nearing term. These findings may be relevant to the management of preterm infants and may relate to the longer term myocardial dysfunction observed in affected adults., (Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background: The long-term prognosis of hypoplastic left heart syndrome is limited by progressive right ventricular dysfunction. The aim of this study was to determine the trends in single right ventricular systolic function between staged palliative surgeries using speckle-tracking and conventional echocardiography., Methods: There were 76 patients with functionally single right ventricles at the (1) pre-Norwood (n = 26), (2) pre-bidirectional cavopulmonary anastomosis (BCPA; n = 19), (3) pre-Fontan (n = 16), and (4) post-Fontan (n = 15) stages, compared with 30 controls of similar ages. Speckle-tracking-derived longitudinal and circumferential strain and strain rate, postsystolic strain index, and mechanical dyssynchrony index were compared with conventional measures of ventricular function. Differences between stages were analyzed using analysis of variance (P < .05)., Results: Strain rate was highest at the pre-Norwood stage and decreased at the other stages (longitudinal P < .0001, circumferential P = .0002), as opposed to controls, in whom strain rate was maintained. Longitudinal strain was significantly decreased at the pre-BCPA stage compared with the pre-Norwood stage (P = .004), but circumferential strain was maintained, resulting in a corresponding decrease in the ratio of longitudinal to circumferential strain, which failed to resemble that of controls. Longitudinal (P = .003) and circumferential (P = .002) postsystolic strain indices were greatest at the pre-BCPA stage., Conclusions: A decline in contractility occurred at the pre-BCPA stage. Although there was evidence of adaptation of the single right ventricle, this failed to resemble the normal left ventricle and may be insufficient to handle the chronic volume load or insult from previous surgery. These findings suggest an intrinsic inability of the single right ventricular myocardium to fully adapt to chronic systemic pressures., (Copyright © 2014 American Society of Echocardiography. All rights reserved.)

Background: Single ventricle (SV) exercise performance is impaired and limited by reduced ventricular preload reserve. The atrium modulates ventricular filling, and enhancement of atrial compliance can increase cardiac performance. We aimed to study atrial mechanics in SV hearts across staged surgical palliation compared with healthy children by using novel speckle-tracking echocardiography techniques., Methods: A cross-sectional study of 81 patients with SV (1 day to 6.5 years) at 4 stages of surgical palliation (presurgery, 22; prebidirectional cavopulmonary anastomosis, 23; pre-Fontan, 22; post-Fontan, 14). The dominant atrium was assessed with speckle-tracking echocardiography for active (εact), conduit (εcon), and reservoir (εres) strain; strain rate (SR); and εact/εres ratio before each stage of surgical palliation. Findings were compared with the left atrium of 51 healthy children (1 day to 5.5 years)., Results: Single ventricle atrial size was increased (P < .01), and atrial εres was decreased (P < .01) compared with healthy controls. SV atrial εcon (P < .01) and SRcon (P < .0001) was decreased, increased εact persisted (P < .05), and εact/εres was increased (P < .001) between surgical stages. Although the expected maturational trend of increasing εcon, decreasing εact, and εact/εres occurred in SV, they lagged behind healthy maturational changes (P < .0001)., Conclusion: Single ventricle atrium is dilated, has deceased compliance, decreased early diastolic emptying, and increased reliance on active atrial contraction for ventricular filling. This deviates from normal early childhood maturational changes and appears to parallel those of an atrium facing early ventricular diastolic dysfunction., (Crown Copyright © 2013. Published by Mosby, Inc. All rights reserved.)

Background: Differences in single right ventricle (SRV) and single left ventricles (SLV) function are poorly described, although myocardial dysfunction is an important risk factor for morbidity and mortality. The aims of this study were to compare function between patients with SRVs and those with SLVs using newer echocardiographic techniques and to determine differences across staged palliation., Methods: In this cross-sectional study comparing 30 patients with SRVs and 30 with SLVs of similar ages (2.5 ± 1.7 vs 2.6 ± 1.6 years), patients were matched for surgical stage (20 pre-bidirectional cavopulmonary anastomosis, 20 pre-Fontan, and 20 post-Fontan patients). Circumferential and longitudinal strain, strain rate (SR), early diastolic SR, postsystolic strain index, and myocardial dyssynchrony index were measured. Comparisons between SRV and SLV parameters were made as a whole group and by subanalysis at each surgical stage., Results: Patients with SRVs had reduced systolic SRs (circumferential: -1.0%/sec vs -1.2%/sec, P = .01; longitudinal: -1.1%/sec vs -1.3%/sec, P = .002), reduced early diastolic SRs (circumferential: 1.4%/sec vs 1.9%/sec, P = .03; longitudinal: 1.6%/sec vs 2.2%/sec, P = .001), and increased circumferential postsystolic strain indexes (8% vs 0%, P < .0001). Subanalysis at each surgical stage showed that the greatest disparity in systolic parameters occurred before bidirectional cavopulmonary anastomosis (longitudinal SR, P = .009; postsystolic strain index, P = .005) and that parity was regained after the Fontan procedure, while traditional diastolic parameters (E velocity, P = .004; E/E' ratio, P = .0003) were reduced in patients with SRVs after the Fontan procedure., Conclusions: The SRV has reduced contractility and diastolic function compared with the SLV. Ventricular systolic performance in patients with SRVs was poorest before bidirectional cavopulmonary anastomosis, while differences in diastolic function were more prominent after Fontan completion., (Crown Copyright © 2012. Published by Mosby, Inc. All rights reserved.)

Background: The systemic right ventricle in palliated hypoplastic left heart syndrome (HLHS) has relatively reduced longitudinal compared with circumferential deformation, a pattern of contraction more akin to the normal left ventricle, which presumably improves right ventricular (RV) pumping efficiency. The aim of this study was to test the hypothesis that these changes in the RV contraction pattern in infants with HLHS are present prenatally., Methods: Echocardiograms from 48 fetuses with HLHS were retrospectively compared with those from appropriately grown RV and left ventricular controls. Ventricular function was assessed using Velocity Vector Imaging velocity, tissue deformation, two-dimensional echocardiography, and Doppler flow parameters., Results: Fetuses with HLHS demonstrated reduced peak global RV longitudinal velocity (P < .01), strain (P < .001), and displacement (P < .05), while radial displacement was increased (P < .001) compared with the normal fetal right ventricle. Mean RV diameter was increased in HLHS (P < .001), but length was unchanged. The ratio of longitudinal to circumferential deformation was reduced in HLHS compared with the normal right ventricle (P < .001) and equivalent to the normal left ventricle. Tricuspid inflow peak A-wave velocity (P < .01), A-wave duration, A-wave inflow fraction, RV Tei index (P < .05 for all), and inferior vena cava A-wave reversal (P < .0001) were increased in HLHS., Conclusions: The fetal right ventricle in HLHS becomes more spherical because of increased RV diameter. It has relatively reduced longitudinal compared with circumferential deformation and an increased reliance on atrial contraction for ventricular filling. These findings are similar to postnatal changes observed in the systemic right ventricle in palliated congenital heart disease, suggesting that ventricular remodeling is initiated in fetal life., (Copyright © 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)