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Background: Subjective assessment of right ventricular (RV) function by neonatal echocardiography lacks validation. Incorrect diagnostic assignment in patients with suspected pulmonary hypertension (PH) may lead to unnecessary treatment or missed treatment opportunities. Methods: Six evaluators (experts [n = 3], novice [n = 3]) were asked to independently rate RV characteristics (global function, dilation, and septal flattening) based on standardized echocardiography images. We randomly selected 60 infants, ≥35 weeks gestation at birth, of whom 30 were clinically unwell with acute pulmonary hypertension (aPH) and 30 were healthy controls. aPH was defined by echocardiography presence of right‐left shunting across transitional shunts or elevated right ventricular systolic pressure as estimated by the magnitude of the regurgitant jet across the tricuspid valve with impaired oxygenation. Inter‐rater comparative evaluation within groups and between groups was performed using Kappa statistics. Results: Global agreement between evaluators for subjective assessment of RV function (0.3 [0.03], P < 0.001), size (0.14 [0.02], P < 0.001), and septal flattening (0.2 [0.02], P < 0.001) was uniformly poor. Agreement in RV function assessment was marginally better for both expert (0.32 [0.08], P < 0.001 vs 0.13 [0.081], and P < 0.001) and novice (0.4 [0.08], P < 0.001 vs 0.06 [0.07], and P < 0.001) evaluators. Overall, the diagnosis of aPH vs control was misclassified in 18% of cases. Conclusion: This study demonstrated significant variability in qualitative assessment of RV size and function by trained evaluators, regardless of level of expertise attained. The reliability of objective measures of RV hemodynamics requires prospective evaluation. [ABSTRACT FROM AUTHOR]

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Objective This article compares hemodynamic characteristics of neonates with hypoxic ischemic encephalopathy (HIE) receiving therapeutic hypothermia (TH) with normal versus abnormal brain magnetic resonance imaging (MRI). Methods Serial echocardiography (echo) was performed within 24 hours, after 48 to 72 hours of cooling, within 24 hours of normothermia, and after starting feeds. Pulmonary hemodynamics, cardiac output, and ventricular function were evaluated. All neonates underwent brain MRI (day 4-5), per clinical standard of care. Clinical cardiovascular and echocardiography characteristics were compared between patients with normal versus abnormal MRI. Cardiovascular changes during TH and after rewarming were identified. Results Twenty neonates at median gestation and birth weight of 40 weeks (inter-quartile range [IQR]: 39, 41) and 3,410 g (IQR: 2,885, 4,093), respectively, were enrolled. Increased median left ventricular output (LVO) (106-159 mL/kg/min, p < 0.001) and reduced isovolumic relaxation time (IVRT) (48-42 ms, p < 0.001) were seen after rewarming. Echocardiography evidence of pulmonary hypertension (PH) was identified in five neonates. Eight neonates (40%) had brain injury identified on MRI (watershed [n = 4], basal ganglia [n = 4]); this subgroup were more likely to have echo evidence of PH at 24 hours. Conclusion Longitudinal changes in cardiac output were noted in neonates with HIE during TH and rewarming. Echocardiography evidence of PH, however, was associated with abnormal MRI brain. The prognostic relevance of these physiologic changes requires more comprehensive delineation. [ABSTRACT FROM AUTHOR]

Background The transitional circulation and its effect on myocardial performance are poorly understood in preterm infants. Aims We assessed myocardial performance in infants less than 29 weeks gestation in the first 48 h of life using a comprehensive echocardiographic assessment. Design Infants < 29 weeks gestation were prospectively enrolled. Small for gestation, infants on inotropes and/or inhaled nitric oxide and septic infants were excluded. Conventional echocardiography, left ventricular (LV), septal and right ventricular (RV) tissue Doppler imaging (TDI) and tissue Doppler-derived strain and strain rate (SR), tricuspid annular plane systolic excursion (TAPSE) and global RV fractional area change (FAC) were assessed at a median of 10 and 45 h post-delivery. Results Fifty-four infants with a median [IQR] gestation and birth weight of 26.5 weeks [25.8–28.0 weeks] and 915 g [758–1142 g] were included. There was no change in shortening or ejection fraction across the two time points. Systolic and diastolic TDI of the LV, septum and RV increased across the two time points (all p values ≤ 0.01). There was an increase in septal peak systolic and early diastolic SR (p = 0.002). Septal systolic strain and late diastolic SR did not change. With the exception of RV strain and early diastolic SR, all RV functional parameters including SR, late diastolic SR, TAPSE, and FAC increased across the two time points (all p values < 0.01). Conclusion Describing the normal hemodynamic adaptations in stable preterm infants during the transitional period provides the necessary information for the assessment of those parameters in various disease states. [ABSTRACT FROM AUTHOR]