Role of patent ductus arteriosus in preterms in long-term outcome.

OBJECTIVE: This study aimed to determine long-term neurodevelopmental outcome and cerebral oxygenation in extremely preterm infants, comparing those with a hemodynamic significant patent ductus arteriosus (hsPDA) to those without. STUDY DESIGN: We included infants born before 28 weeks of gestation from 2008 to 2010 with routine echocardiography. Prior to echocardiography, regional cerebral oxygen saturation was measured. At 5 years of age, we evaluated neurodevelopmental outcomes using the Movement Assessment Battery for Children 2nd Dutch edition for motor skills and the Wechsler Preschool and Primary Scale of Intelligence 3rd Dutch edition for cognition. RESULTS: A total of 66 infants (gestational age 26.6 ± 0.9 weeks, birth weight 912 ± 176 g) were included, 34 infants with a hsPDA (including treatment). The group infants with hsPDA showed lower pre-closure cerebral saturation levels (58.2 % ±7.8 % versus 62.8 % ±7.0 %; p = 0.01). At 5 years, impaired motor outcome occurred more often in infants with hsPDA (17 (53 %) vs. 7 (23 %); p = 0.01). In multivariate analysis existence of hsPDA remained unfavourably related to the motor subdomain "aiming and catching". There were no potential effects of hsPDA on cognitive performance at 5 years of age. CONCLUSION: Treatment-receiving infants with hsPDA appear to exhibit motor deficits, specifically in "aiming and catching", by the age 5. Persistent ductal patency could be a contributing factor.

Cardiac Valve Annulus Diameters in Extremely Preterm Infants: A Cross-Sectional Echocardiographic Study.

BACKGROUND: With the increasing incidence of births of very preterm very-low-birth-weight infants, there is a demand for echocardiographic reference values of cardiac dimensions. OBJECTIVES: The aim of this study was to provide reference values of cardiac valve annulus diameters in a cohort of extremely preterm very-low-birth-weight neonates and to correlate these with patient characteristics. METHODS: Valve diameters of 376 infants of < 32 weeks' gestation and with a birth weight of ≤2,000 g were measured using 2-dimensional echocardiography. Correlations between valve diameters and patient characteristics (birth length/weight, body surface area, gestational age, and sex) were assessed. Birth weight was used to establish linear regression models. Inter- and intraobserver agreement was assessed through intraclass correlation coefficient (ICC) analysis. RESULTS: Substantial variability was found (aortic valve mean [standard deviation; range]: 5.0 mm [0.6; 3.7-6.5]; pulmonic valve: 5.8 mm [0.8; 3.4-7.9]; mitral valve: 8.0 mm [1.0; 5.5-10.5]; tricuspid valve: 7.6 mm [1.2; 4.9-10.6]). There was a moderate correlation between birth weight and valve diameter (R2 aortic valve: 0.36; pulmonic valve: 0.20; mitral valve: 0.24; tricuspid valve: 0.24). Adequate intraobserver (ICC range 0.74-0.91) and interobserver agreement (ICC range 0.77-0.89) was found. CONCLUSIONS: Our study provides ready-to-use reference values for cardiac valve annulus diameters for extremely preterm infants.

Additional value of three-dimensional rotational angiography in the diagnostic evaluation and percutaneous treatment of children with univentricular hearts.

AIMS: Complex single ventricle topography, changes in vessel geometry after surgical steps and subsequent stenoses are difficult to visualise with biplane conventional angiography (CA). This study aimed to investigate the additional value of three-dimensional rotational angiography (3DRA) compared to CA for diagnostic and interventional purposes in children with univentricular hearts. METHODS AND RESULTS: Demographic data, clinical data and catheterisation details of both imaging techniques were collected retrospectively. Image quality, interventional success and the additional value of 3DRA were reviewed and scored. Between January 2003 and March 2017, 140 patients underwent 183 CAs and 107 3DRAs. 3DRA image quality was superior to CA with fewer diagnostic angiographies performed (p<0.001). Intervention rate (p<0.001) and interventional success (p=0.03) were higher with 3DRA, while complication rates were similar. Mean radiation was lower in the 3DRA group, reaching significance pre-PCPC. 3DRA was considered of additional value in imaging of cardiovascular anatomy, collaterals, stenoses, and vessel-vessel and vessel-bronchi interactions. CONCLUSIONS: In univentricular hearts, 3DRA provides superior image quality when compared to CA. Furthermore, 3DRA is performed with fewer diagnostic angiographies, less radiation and higher interventional success.

Normative Values of Aortic Arch Structures in Premature Infants.

BACKGROUND: Aortic arch abnormalities represent 5% to 8% of all congenital heart disease. Measurements of the aortic arch dimensions on two-dimensional echocardiographic images remain of critical importance in the diagnosis of aortic arch pathology. To define aortic hypoplasia or coarctation, measured dimensions must be compared with normal values. Normal values have been described for children of all ages in earlier studies. However, normative data for premature infants are not yet available. Therefore, the aim of this study was to develop normative data in a cohort of premature infants, which could be used in the diagnosis of aortic arch abnormalities. METHODS: A single-center study was conducted in a large population of premature infants with gestational ages of ≤32 weeks without hemodynamically important congenital heart disease, chromosomal abnormalities, and/or major cerebral congenital malformations. Two-dimensional echocardiographic measurements of four aortic arch structures were made on the second, fourth, and sixth days after birth. RESULTS: Three hundred eighty-five preterm patients were included. No differences in dimensions were found among days 2, 4, and 6. The dimension of the isthmus showed no significant relation to the existence of a patent ductus arteriosus. Reference intervals with mean and SD were calculated across the range of birth weight. Regression analysis was performed with multiple determinants in different models. The best predictive value was found for birth weight in a cubic model. CONCLUSIONS: This work provides regression equations for the calculation of Z scores and reference intervals for aortic arch dimensions in a cohort of preterm infants born at gestational ages of ≤32 weeks. The normative data can be used in diagnosis and decision making involving aortic arch pathology in premature infants.

Early detection of prenatal cardiocirculatory compromise in small for gestational age infants.

BACKGROUND: Impairment of gas and substrate exchange through the placenta leads to fetal hypoxia and growth restriction. Oxygenation of vital organs is maintained with preferential perfusion at the expense of less vital organs, challenging the fetal cardiovascular system. OBJECTIVES: To identify cardiovascular compromise in preterm small for gestational age (SGA) infants using the cardiac biomarker B-type natriuretic peptide (BNP), which indicates the workload of the myocardium. METHODS: In this retrospective case-control study, 26 SGA infants born at less than 32 weeks of gestation from October 2009 to October 2010 were matched for gestational age and month of birth with 26 appropriate for gestational age (AGA) infants. Antenatal Doppler ultrasound was used to identify fetal hemodynamic changes by determination of the pulsatility index (PI) of the middle cerebral artery (MCA-PI), umbilical artery (UA-PI) and veins of the ductus venosus (DV-PIV). These indices were compared with BNP levels obtained within 6 h after birth. RESULTS: Antenatal PIs of MCA, UA and DV were significantly related to elevated BNP levels after birth in SGA infants, but not in AGA infants (SGA: MCA-PI = r(2) 0.23, p < 0.05; UA-PI = r(2) 0.46, p < 0.01; DV-PIV = r(2) 0.31, p < 0.05). Furthermore, signs of perinatal (chronic) asphyxia coincided with elevated levels of BNP. SGA was related to more postnatal cardiocirculatory complications. No significant relations between postnatal cardiac ultrasound measurements, placenta size and BNP were found. CONCLUSION: BNP levels were elevated early after birth in SGA infants and corresponded positively with Doppler indices of circulatory compromise. This suggests an increased workload of the myocardium.

Early end-tidal carbon monoxide levels, patency of the ductus arteriosus and regional cerebral oxygenation in preterm infants.

BACKGROUND: Carbon monoxide (CO), a relaxant regulator of muscle tone and marker of oxidative stress and inflammation, can be measured in exhaled air by determination of end-tidal CO corrected for CO in ambient air (ETCOc). OBJECTIVE: Increased endogenous production of CO may influence patency of the ductus arteriosus, cerebral perfusion and, subsequently, cerebral oxygenation. The aim was to study the relation between early ETCOc levels, hemodynamically significant patent ductus arteriosus (hsPDA) and cerebral oxygenation (rScO2) in preterm infants <32 weeks' gestational age and determine predictive values of ETCOc for hsPDA. METHODS: ETCOc was measured in 91 infants within the first 24 h after birth. A hsPDA was diagnosed according to echocardiographic indices. In 78/91 infants, rScO2 was monitored with near-infrared spectroscopy to assess cerebral oxygenation. RESULTS: ETCOc values were significantly higher in infants who subsequently developed hsPDA (2.3 ± 0.7 ppm) vs. no-hsPDA (1.7 ± 0.6 ppm), p < 0.001. With a cut-off value of 2.5 ppm, positive and negative predictive values of ETCOc for hsPDA were 55 and 88%, respectively. rScO2 values were not different between the two groups (64 ± 1 vs. 65 ± 3%, NS). CONCLUSIONS: The higher ETCOc values in hsPDA infants early after birth reflect the early relaxant state of ductal muscular tone. ETCOc <2.5 ppm within 24 h after birth may predict the subsequent absence of hsPDA. ETCOc showed no correlation with cerebral oxygenation in both groups.

Is cerebral oxygen supply compromised in preterm infants undergoing surgical closure for patent ductus arteriosus?

BACKGROUND: A haemodynamically important patent ductus arteriosus (PDA) is a risk factor for brain damage in preterm infants. The authors previously reported lower regional cerebral oxygen saturation (rScO(2)) in infants with PDA, which recovered after administration of indomethacin. However, PDA ligation has been reported to pose an even higher risk of neurodevelopmental impairment. OBJECTIVE: To investigate the impact of surgical closure of PDA on rScO(2) and cerebral fractional tissue oxygen extraction (cFTOE), measured by near-infrared spectroscopy, and on amplitude-integrated electro-encephalography (aEEG) measured brain activity. DESIGN/METHODS: In 20 preterm infants (gestational age 24.7-30.4 weeks; birth weight 630-1540 g), blood pressure, arterial saturation, rScO(2), cFTOE and aEEG were monitored before, during and up to 24 h after surgery. RESULTS: Before surgery, median (range) rScO(2) was 53% (41-68%), and during surgery, but before ductal clipping, it was 46% (31-89%). Eleven infants showed a drop in blood pressure and 13 infants a drop in rScO(2) during surgery (range 2-21%), accompanied by a decrease in aEEG amplitude. Twelve infants had rScO(2) values below 50% during surgery, with five being below 40%. Only at 24 h after surgery was rScO(2) higher (61% (36-85%), p<0.05) and cFTOE values lower (0.38 (0.09-0.61); p<0.05) compared with preclipping values. CONCLUSION: Ductal ligation poses a risk for a further decrease in already compromised cerebral oxygenation in preterm infants.