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We aimed to evaluate the accuracy and reproducibility of right ventricular output (RVO) using different anatomical landmarks: the internal pulmonary valve diameter (PVD) between the valve hinge points (hinge-PVD) according to the traditional technique, and PVD between the valve leaflet tips (tip-PVD). This was a retrospective analysis of prospective collected data. All neonates with echocardiographic measurements of RVO and left ventricular output (LVO) without congenital heart disease, including patent ductus arteriosus and patent foramen ovale > 3 mm, were included. Accuracy was assessed by comparison with LVO. Intra- and inter-observer reproducibility of the off-line analysis were assessed. Forty-five neonates were included. RVO calculation with tip-PVD was more accurate than hinge-PVD in comparison with LVO, r2 0.712 versus 0.464, bias (95% limits of agreement) 1.4 mL/kg/min (−26–29 mL/kg/min) versus 61 mL/kg/min (−11–132 mL/kg/min), respectively. Both hinge-PVD and tip-PVD presented similar reproducibility, with an intra-observer bias (95% LOA) of 0.3 (−1.0–0.5) and –0.2 (−0.8–0.5) respectively, and an inter-observer bias of 0.1 (−1.3–1.6) and 0.1 (−1.4–1.6). RVO calculation using tip-PVD was more accurate than the conventional technique, with similar reproducibility.

Objective The perfusion index (PI) is a noninvasive marker derived from photoelectric plethysmographic signals in pulse oximetry in the evaluation of peripheral perfusion. This study was aimed to determine the correlation between PI and left ventricular output (LVO) in healthy late preterm infants at 48 th hour of life. Study Design With new generation pulse oximeter (MASIMO Rad 7 Oximeter) pre- and post-ductal PI values were recorded from healthy late preterm babies at the 48 th hour of life. PI was determined simultaneously with LVO as measured by transthoracic echocardiography. Results A total of 50 late preterm babies were included in the study. The mean gestational age of the cases was 35.4 ± 0.7 weeks and the birth weight was 2,586 ± 362 g. Mean pre- and post-ductal PI values at the postnatal 48 th hour of babies' life were found to be 2.0 ± 0.9 and 1.7 ± 1.1. The mean LVO value was 438 ± 124, LVO/kg 175 ± 50. When the LVO value was normalized according to the babies' body weight, there was no statistically significant correlation between the pre- and post-ductal PI and the LVO/kg value (r <0.2, p >0.05 in both comparisons). Conclusion There was no correlation between pre- and post-ductal PI and LVO values in healthy late preterm infants. This may be due to the failure of the LVO, a systemic hemodynamic parameter, to accurately reflect microvascular blood flow due to incomplete maturation of the sympathetic nervous system involved in the regulation of peripheral tissue perfusion in preterm babies. Key Points No correlation found between PI and LOV in preterm babies. LVO cannot adequately reflect peripheral blood flow. Sympathetic nervous system is immature in preterm infants. [ABSTRACT FROM AUTHOR]

Background: Assessment of systemic blood flow helps in choosing the appropriate drug for managing critically ill neonates with poor perfusion. Superior vena cava (SVC) flow has the potential to become a bedside gold standard method for this purpose. Aims and Objectives: To find out normal superior vena cava (SVC) flow and its correlation with left ventricular output (LVOT) in late preterm and term neonates. Materials and Methods: A cross sectional observational study was carried out at a tertiary care teaching hospital where SVC flow and left ventricular output were measured in hundred intramural healthy neonates (50 late pre-term, weighing 1500g or more and 50 term, weighing 2500g or more). SVC flow was correlated with LV output in both groups. Pearson correlation coefficient was calculated to correlate between two variables. p < 0.05 was considered significant. Results: Median SVC flow in late pre-term group was 57.83ml/kg/min, and in term neonates was 56ml/kg/min. In late pre-term babies correlation of SVC flow with LV output was better in comparison to term group (r-0.56, p

Background: Despite the widespread use of superior vena cava (SVC) flow as a marker of systemic blood flow from the upper body, no previous studies have systematically evaluated the correlation between SVC flow and other echocardiography measures of systemic blood flow in the context of different patterns of patent ductus arteriosus (PDA) shunt direction Methods: A retrospective cohort study of preterm infants (< 30 weeks, < 21 days of life) who underwent comprehensive targeted neonatal echocardiography (TnECHO) was performed. Patients were categorized as follows: (i) Hemodynamically significant left‐to‐right shunt; (ii): Bidirectional shunt; (iii) No PDA or insignificant shunt. SVC flow, as measured by two distinct methods, was compared to left and right ventricular outputs (LVO and RVO). Intra‐ and inter‐observer reliability testing was performed Results: In total, 45 patients were included (15 in each group) with a median [IQR] weight of 720 [539, 917] grams at the time of assessment. SVC dimensions and flow measurements were not different between the groups, although patients with left‐to‐right shunt had higher LVO/RVO ratio. SVC flow, as estimated using the modified method, had a strong correlation with LVO (r =.63, p = 0.012) and RVO (r =.635, p = 0.011) in patients with no PDA. Inter‐ and intra‐observer reliability were both stronger for LVO and RVO when compared to SVC flow measurements Conclusion: SVC flow was comparable across all three groups irrespective of higher LVO and LVO/RVO ratio in patients with left‐to‐right shunts. This may reflect poor measurement reliability or compensation for left‐to‐right ductal shunt by increased LVO to maintain systemic perfusion. [ABSTRACT FROM AUTHOR]

Background: Assessment of systemic blood flow helps in choosing the appropriate drug for managing critically ill neonates with poor perfusion. Superior vena cava (SVC) flow has the potential to become a bedside gold standard method for this purpose. Aims and Objectives: To find out normal superior vena cava (SVC) flow and its correlation with left ventricular output (LVOT) in late preterm and term neonates. Materials and Methods: A cross sectional observational study was carried out at a tertiary care teaching hospital where SVC flow and left ventricular output were measured in hundred intramural healthy neonates (50 late pre-term, weighing 1500g or more and 50 term, weighing 2500g or more). SVC flow was correlated with LV output in both groups. Pearson correlation coefficient was calculated to correlate between two variables. p < 0.05 was considered significant. Results: Median SVC flow in late pre-term group was 57.83ml/kg/min, and in term neonates was 56ml/kg/min. In late pre-term babies correlation of SVC flow with LV output was better in comparison to term group (r-0.56, p<0.0001, and r-0.40, p=0.0024respectively). Conclusions: SVC flow better represents systemic blood flow in late preterm neonates in comparison to term neonates. [ABSTRACT FROM AUTHOR]

Reversal of shunting across the ductus arteriosus from right-to-left to left-to-right is a characteristic feature of the birth transition. Given that immediate cord clamping (ICC) followed by an asphyxial cord clamp-to-ventilation (CC-V) interval may augment left ventricular (LV) output and central blood flows after birth, we tested the hypothesis that an asphyxial CC-V interval accelerates the onset of postnatal left-to-right ductal shunting. High-fidelity central blood flow signals were obtained in anesthetized preterm lambs (gestation 128 ± 2 days) after ICC followed by a nonasphyxial (~40 s, n = 9) or asphyxial (~90 s, n = 9) CC-V interval before mechanical ventilation for 30 min after birth. Left-to-right ductal flow segments were related to aortic isthmus and descending aortic flow profiles to quantify sources of ductal shunting. In the nonasphyxial group, phasic left-to-right ductal shunting was initially minor after birth, but then rose progressively to 437 ± 164 ml/min by 15 min (P < 0.001). However, in the asphyxial group, this shunting increased from 24 ± 21 to 199 ± 93 ml/min by 15 s after birth (P < 0.001) and rose further to 471 ± 190 ml/min by 2 min (P < 0.001). This earlier onset of left-to-right ductal shunting was supported by larger contributions (P < 0.001) from direct systolic LV flow and retrograde diastolic discharge from an arterial reservoir/windkessel located in the descending aorta and its major branches, and associated with increased pulmonary arterial blood flow having a larger ductal component. These findings suggest that the duration of the CC-V interval after ICC is an important modulator of left-to-right ductal shunting, LV output and pulmonary perfusion at birth. [ABSTRACT FROM AUTHOR]

Perfusion index (PI) is a non-invasive marker of peripheral perfusion which is detected by an oximeter. We aimed to assess the correlation between PI and left ventricular output (LVO) in healthy term infants at the time of the screening for congenital heart disease (CHD). PI was measured at 48±2 h of life in the infant's right hand (PIrh) and in one foot (PIf) contemporary to SpO2 for CHD screening. Heart ultrasound was performed immediately after the screening procedure for measuring LVO. Forty-nine healthy term infants were studied. PIrh and PIf were 1.9 ± 0.6 and 1.9 ± 0.8, respectively, and their values were significantly correlated (p < 0.0001) with a coefficient r = 0.8. Bland-Altman analysis shows a mean difference of -0.06 ± 0.47 (95%LOA -0.98-0.86). PIrh correlates with LVO (r = 0.68) and LVO/kg (r = 0.61) with an increase of 151 mL/min (95%CI 103-198) of LVO and 42 mL/kg/min (95%CI 26-58) of LVO/kg per point of PIrh. PIf correlates with LVO (r = 0.74) and LVO/kg (r = 0.73) with an increase of 123 mL/min (95%CI 90-155) of LVO and 37 mL/kg/min (95%CI 27-47) of LVO/kg per point of PIf.Conclusion: PI is significantly correlated with LVO in healthy term infants. These results support the theoretical potential role of PI in the CHD screening. What is Known: • Perfusion index is an indirect measure of perfusion which depends on cardiac output and peripheral vascular resistance whose normal values have been documented in term and preterm infants in the first days of life. • Perfusion index has been proposed for the screening of congenital heart disease with duct-dependent systemic circulation in term infants. What is New: • Perfusion index shows a significant correlation with the left ventricular output in term infants at the moment of the screening for congenital heart disease. • Perfusion index might have a theoretical role in improving the accuracy of pulse oximetry in the screening of CHD associated to low systemic flow. [ABSTRACT FROM AUTHOR]

Background: During neonatal transition, ductus arteriosus (DA) flow changes from right-to-left to left-to-right and contributes considerably to the increase in pulmonary blood flow. Large transpulmonary pressures generated by crying at birth can influence the DA shunt. Objective: This study aimed to assess differences in DA shunt during quiet breathing and crying directly after birth. Methods: In healthy term infants born by caesarean section, echocardiography was performed at 2, 5 and 10 min after birth. The velocity time integral of DA flow, DA flow ratio (right-to-left/left-to-right flow) and left ventricular output were assessed using echocardiography. Shunting was compared within each patient during crying and quiet breathing, and between time points. Results: A total of 23 infants were studied. The velocity time integral of left-to-right shunting was significantly larger during the inspiratory phase of crying than during quiet breathing [12.8 (9.2-17.4) vs. 5.9 (3.9-7.7) cm at 2 min, p < 0.0001; 14.3 (11.5-22.3) vs. 6.7 (4.1-11.1) cm at 5 min, p < 0.0001, and 18.6 (14.8-22.5) vs. 6.7 (4.4-10.7) cm at 10 min, p < 0.0001, after birth]. The increase in left-to-right shunting during crying was independent from the cardiac cycle as the QRS start of shunt interval time was 138 (82) ms during crying and 156 (35) ms during quiet breathing (n.s.). The DA flow ratio was lower in infants who cried at 0-1 time points versus those who cried at 2-3 time points (n.s.) out of the 3 time points measured. Left ventricular output was higher in infants who cried at 2-3 time points versus 0-1 time points (n.s.). Conclusion: Crying at birth significantly influences the DA shunt during transition. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Non-invasive cardiac output monitoring (NICOM; NICOM™) may be useful in the management of extremely premature preterm infants. Objectives: To evaluate a new bioreactance-based method of continuous NICOM in preterm infants following patent ductus arteriosus (PDA) ligation. Methods: Infants underwent three paired NICOM and echocardiography assessments of stroke volume (SV) and left ventricular output (LVO) in the postoperative period: at 1, 6-8, and 16-18 h postoperatively. NICOM- and echocardiography-measured SV and LVO during those periods were compared using Bland-Altman analysis and the intraclass correlation coefficient (ICC). Results: Twenty-five infants with a median (interquartile range) gestational age and birth weight of 25.0 weeks (24.5-25.9) and 700 g (615-775), respectively, were included. The overall systematic bias (limits of agreement) across all time points between the NICOM and echocardiography SV readings was 39% (8-69) with NICOM consistently underestimating echocardiography values. There was moderate consistency between NICOM and echocardiography SV values (ICC 0.78, p < 0.001). Compared with the 1-hour scans, the 6- to 8- and 16- to 18-hour scans had increased biases of 7.9% (95% CI 2.5-13.2) and 9.7% (95% CI 3.6-15.8), respectively. Conclusion: Continuous LVO measurement using NICOM was feasible and demonstrated a consistent systematic bias compared with echocardiography in unstable extremely preterm infants without a PDA ligation. NICOM may be used as a trending tool for continuous monitoring in this population, but wide limits of agreement and increasing bias over time suggest it is not interchangeable with echocardiography. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Targeted milrinone treatment for low left ventricular output (LVO) reduces the incidence of acute cardiorespiratory instability following ligation of patent ductus arteriosus (PDA) in preterm infants. Despite this, some infants continue to experience postoperative deterioration. Adrenal insufficiency related to prematurity has been postulated as a possible mechanism. Objectives: To describe adrenal function in premature infants undergoing PDA ligation and to investigate its association with pre- and postoperative clinical and echocardiography-derived indices of disease severity. Methods: A retrospective cohort study was conducted over a 2-year period on infants who underwent PDA ligation and had preoperative adrenocorticotropic hormone (ACTH) stimulation. All infants were screened by echocardiography for low LVO at 1 h after surgery and treated with intravenous milrinone if LVO <200 ml/kg/min. The primary outcome evaluated was low LVO at 1 h after surgery. Secondary outcomes included hypotension and oxygenation and ventilation failure occurring within 24 h. Results: A total of 35 infants at a median gestation of 25.4 (24.5-26.4) weeks and weight at birth of 700 (600-810) g were included. Baseline median cortisol measured preoperatively was 202 (137-403) nmol/l. Following the ACTH stimulation test, 3 infants had cortisol ≤500 nmol/l while 15 had ≤750 nmol/l. There was no association seen between any cortisol value and low LVO postoperatively. Post-ACTH cortisol ≤750 nmol/l was significantly associated with hypotension (p = 0.03) and oxygenation (p = 0.04) and ventilation (p = 0.008) failure. Receiver-operator characteristic curve showed a high predictive value of post-ACTH cortisol for all clinical outcomes. Conclusions: Post-ACTH cortisol (≤750 nmol/l) may be associated with clinical indices of postoperative cardiorespiratory instability. Relative adrenal insufficiency may play a role in the etiology of post-PDA ligation hemodynamic and respiratory instability. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objectives: Non-invasive cardiac output monitoring is a potentially useful clinical tool in the neonatal setting. Our aim was to evaluate a new method of non-invasive continuous cardiac output (CO) measurement (NICOM™) based on the principle of bioreactance in neonates. Methods: In this prospective observational study, 10 neonates underwent 97 paired NICOM and echocardiography (echo) assessments of left ventricular output (LVO). For each neonate, NICOM measurements of left ventricular stroke volume (SV) and LVO over a 2- to 4-hour period were correlated with blinded, simultaneous, discrete echo measurements of SV and LVO. The precision and accuracy of the NICOM monitor relative to echo during periods of steady state were assessed. Results: The infants' median birth weight was 2.72 kg (IQR 1.56-3.23 kg, range 1.44-4.00) and their median gestation was 37 weeks (IQR 31-40 weeks, range 31-41). Median NICOM SV and LVO readings were consistently lower than echo (2.6 ml [IQR 1.4-3.2, range 0.6-5.3] vs. 3.5 ml [IQR 2.1-4.4, range 1.1-6.8], and 400 ml/min [IQR 233-476] vs. 559 ml/min [IQR 386-652], p < 0.001). The NICOM LVO readings were lower than the echo readings by a mean of 153 ± 56 ml/kg. NICOM consistently under-read LVO by 31 ± 8%, and this systematic difference was constant across the range of LVOs obtained. There was a strong correlation between NICOM and echo measurements of LVO (r = 0.95, p < 0.001). Conclusion: Non-invasive cardiac output monitoring is feasible in neonates. Further validation studies in neonatal animal experimental models and human neonates need to be conducted before routine clinical use. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the short-term cardiorespiratory effects of a standard red cell transfusion in very low birth weight (<1500 g) infants undergoing intensive care. A total of 37 infants (birth weight 920±230 g, gestational age 27.8±2.1 weeks, age at study 6.1±3.9 days) with indwelling arterial lines were studied when 10 ml/kg of packed donor red cells were transfused based on clinical judgment. Infants with patent ductus arteriosus and/or inotropic treatment were excluded from the study. Oxygen saturation, left ventricular output, stroke volume, systolic, diastolic and mean arterial pressure, heart rate, and capillary refill time were assessed immediately prior to the transfusion and within an hour after the transfusion was completed. Capillary refill time after the transfusion was significantly shorter than prior to the transfusion (2.1±0.9 versus 2.4±1.0 s, P =0.033). Left ventricular output, stroke volume and arterial pressures remained unaltered. Oxygen saturation after the transfusion was lower than before the transfusion (94.0±3.8 versus 95.3±2.5%, P =0.014) despite unaltered oxygen supply. Conclusion: the data suggest that although a red cell transfusion of 10 ml/kg may marginally improve peripheral perfusion, it does not influence cardiac output and arterial blood pressure in normotensive preterm infants. It may, however, cause a transient decrease in oxygen saturation. [ABSTRACT FROM AUTHOR]

Aim: To determine cerebral blood flow using near infrared spectroscopy in extremely preterm infants undergoing high-frequency oscillatory ventilation during the first three days of life. Low cerebral blood flow has been associated with both intra-ventricular haemorrhage and periventricu-lar leucomalacia. It is well established that cerebral blood flow increases over the first three days of life in extremely preterm infants who are conventionally ventilated with intermittent positive pressure ventilation. However, there is no information about cerebral blood flow in preterm babies undergoing high-frequency oscillatory ventilation. In addition, there are concerns that high-frequency oscillatory ventilation may be associated with an increased incidence of intra-ventricular haemorrhage in premature infants. Methods: Thirteen appropriately grown, preterm infants of less than 28 wk gestation who were admitted to the neonatal unit at University College Hospital, London were studied using near infrared spectroscopy. Left ventricular output and right ventricular output were assessed echocardiographically. Results: Extremely preterm infants undergoing high-frequency oscillatory ventilation have remarkably low cerebral blood flow in the first 12 h of life, median 6.7 (range 4.4-11) mls. 100 g -1 min -1 followed by an increase over the subsequent three days. Left ventricular output also increased over the first three days of life, whereas right ventricular output showed no clear relationship with time. Despite low cerebral blood flow only one infant had evidence of major cerebral injury. Conclusion: Cerebral blood flow is extremely low in this group of preterm babies. Despite this extremely low cerebral blood flow, the clinical outcome is good. There was an increase in cerebral blood flow and a corresponding increase in left ventricular output over the first few days of life. [ABSTRACT FROM AUTHOR]

Abstract Background : Cardiocirculatory effects of hemodynamically significant patent ductus arteriosus (hsPDA) have not been systematically studied in extremely low-birth-weight (ELBW) infants with respiratory distress syndrome (RDS). The objective of the present study was to evaluate the effects of hsPDA on the left ventricular output (LVO) and organ blood flows in ELBW infants with RDS. Methods : Extremely low-birth-weight infants (birth-weight <1000 g) treated with surfactant for RDS were studied by serial Doppler flow examinations. Doppler flow variables in 19 infants in whom hsPDA developed (hsPDA group) were compared with those in 19 infants without hsPDA matched for gestational age, birth-weight, and postnatal age (non-hsPDA group). All infants in the hsPDA group had pharmacologic closure of ductus arteriosus when hsPDA developed. Results : Before pharmacological closure of PDA, the hsPDA group had significantly higher LVO, lower blood flow volume of the abdominal aorta, and lower mean blood flow velocities in the celiac artery, superior mesenteric artery, and renal artery than the non-hsPDA group. These alterations in the hsPDA group reverted to the levels in the non-hsPDA group after the closure of PDA and had no deleterious effects on the cardiorespiratory status. No significant differences between the groups were found in mean blood flow velocities of the anterior cerebral artery throughout the study period. Conclusion : These results indicate that although LVO is increased, the splanchnic and renal blood flows are decreased when hsPDA develops in ELBW infants with RDS. The effects of these alterations of LVO and organ blood flows on the cardiorespiratory course seem to be minor when early pharmacologic closure of PDA is done. [ABSTRACT FROM AUTHOR]

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Objective: To assess ductus arteriosus (DA) blood flow directly after birth in healthy term infants after elective caesarean section., Design: In healthy term newborns, echocardiography was performed at 2, 5 and 10 min after birth to monitor cardiac output and DA blood flow. Heart rate (HR) was assessed using ECG., Setting: The delivery rooms of the Leiden University Medical Center., Patients: 24 healthy term infants born after a caesarean section were included in this study., Results: Mean (SD) HR did not change (158 (18) beats per minute (bpm), 5 min (159 (23) bpm) and 10 min (156 (19) bpm). DA diameter decreased from 5.2 (1.3) mm at 2 min to 4.6 (1.3) mm at 5 min (p=0.01) to (3.9 (1.2) mm) (p=0.01) at 10 min. Right-to-left DA shunting was unaltered (median (IQR) 95 (64-154) mL/kg/min to 90 (56-168) mL/kg/min and 80 (64-120) mL/kg/min, respectively (ns)), whereas left-to-right shunting significantly increased between 2 and 5 min (41 (31-70) mL/kg/min vs 67 (37-102) mL/kg/min (p=0.01)) and increased significantly between 2 and 10 min (93 (67-125)) mL/kg/min (p<0.001). Right-to-left/left-to-right shunting ratio decreased significantly from 2.1 (1.4-3.1) at 2 min to 1.4 (1.0-1.8) at 5 min (p<0.0001) and to 0.9 (0.6-1.1) at 10 min (p<0.0001)., Conclusions: DA shunting changes swiftly from predominantly right-to-left shunting to predominantly left-to-right shunting at 10 min after birth, reflecting differential changes in pulmonary and systemic vascular resistance., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objective: To investigate whether changes in cardiac function and cerebral blood flow (CBF) precede the occurrence of peri/intraventricular hemorrhage (P/IVH) in extremely preterm infants., Study Design: In this prospective observational study, 22 preterm infants (gestational age 25.9 ± 1.2 weeks; range 23-27 weeks) were monitored between 4 and 76 hours after birth. Cardiac function and changes in CBF and P/IVH were assessed by ultrasound every 12 hours. Changes in CBF were also followed by continuous monitoring of cerebral regional oxygen saturation (rSO2) and by calculating cerebral fractional oxygen extraction., Results: Five patients developed P/IVH (1 patient grade II and 4 patients grade IV). Whereas measures of cardiac function and CBF remained unchanged in neonates without P/IVH, patients with P/IVH tended to have lower left ventricular output and had lower left ventricle stroke volume and cerebral rSO2 and higher cerebral fractional oxygen extraction during the first 12 hours of the study. By 28 hours, these variables were similar in the 2 groups and myocardial performance index was lower and middle cerebral artery mean flow velocity higher in the P/IVH group. P/IVH was detected after these changes occurred., Conclusions: Cardiac function and CBF remain stable in very preterm neonates who do not develop P/IVH during the first 3 postnatal days. In very preterm neonates developing P/IVH during this period, lower systemic perfusion and CBF followed by an increase in these variables precede the development of P/IVH. Monitoring cardiac function and cerebral rSO2 may identify infants at higher risk for developing P/IVH before the bleeding occurs., (Copyright © 2014 Mosby, Inc. All rights reserved.)

Background: The echocardiographic assessment of circulatory function in sick newborn infants has the potential to improve patient care. However, measurements are prone to error and have not been sufficiently validated. Phase-contrast magnetic resonance imaging (MRI) provides highly validated measures of blood flow and has recently been applied to the newborn population. The aim of this study was to validate measures of left ventricular output and superior vena caval flow volume in newborn infants., Methods: Echocardiographic and MRI assessments were performed within 1 working day of each other in a cohort of newborn infants., Results: Examinations were performed in 49 infants with a median corrected gestational age at scan of 34.43 weeks (range, 27.43-40 weeks) and a median weight at scan of 1,880 g (range, 660-3,760 g). Echocardiographic assessment of left ventricular output showed a strong correlation with MRI assessment (R(2) = 0.83; mean bias, -9.6 mL/kg/min; limits of agreement, -79.6 to +60.0 mL/kg/min; repeatability index, 28.2%). Echocardiographic assessment of superior vena caval flow showed a poor correlation with MRI assessment (R(2) = 0.22; mean bias, -13.7 mL/kg/min; limits of agreement, -89.1 to +61.7 mL/kg/min; repeatability index, 68.0%). Calculating superior vena caval flow volume from an axial area measurement and applying a 50% reduction to stroke distance to compensate for overestimation gave a slightly improved correlation with MRI (R(2) = 0.29; mean bias, 2.6 mL/kg/min; limits of agreement, -53.4 to +58.6 mL/kg/min; repeatability index, 54.5%)., Conclusions: Echocardiographic assessment of left ventricular output appears relatively robust in newborn infant. Echocardiographic assessment of superior vena caval flow is of limited accuracy in this population, casting doubt on the utility of the measurement for diagnostic decision making., (Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Objective: To investigate the differences in cardiac function and arterial biophysical properties between term-born appropriate for gestational age (AGA) infants and small for gestational age (SGA) infants. Our hypothesis was that adaptation to intrauterine growth restriction induces changes in cardiac and arterial indices., Study Design: This was a prospective observational echocardiographic evaluation of cardiac and arterial indices in SGA infants and AGA infants. Demographic and echocardiographic data were compared between 20 inborn term SGA infants with birth weight <3rd percentile for gestational age and 20 AGA infants., Results: The Ponderal index was significantly lower and blood pressure was significantly higher in the SGA infants compared with the AGA infants. Left ventricular output was lower in the SGA infants (170 ± 31 mL/kg/min vs 197 ± 39 mL/kg/min). Diastolic dysfunction was greater in the SGA infants (ie, reduced E and A wave velocities, higher E/A ratio [1.08 ± 0.16 vs 0.85 ± 0.07], and prolonged isovolumic relaxation time [73 ± 6.2 ms vs 62.6 ± 3.6 ms]). Aortic intima-media thickness was significantly greater in the SGA infants (822 ± 105 μm vs 694 ± 52 μm), as were arterial wall stiffness index and input impedance., Conclusion: Cardiac function and arterial biophysical properties were altered in the SGA infants. The findings complement the information on the association between in utero growth and cardiovascular morbidity in later life., (Copyright © 2013 Mosby, Inc. All rights reserved.)