Fetal Cardiology

Umbilical Cord Blood Gas in Newborns with Prenatal Diagnosis of Congenital Heart Disease: Insight into In-Utero and Delivery Hemodynamicsv

Umbilical Cord Blood Gas in Newborns with Prenatal Diagnosis of Congenital Heart Disease: Insight into In-Utero and Delivery Hemodynamics. Adams AD, Aggarwal N, Iqbal SN, Tague L, Skurow-Todd K, McCarter R, Donofrio MT. Pediatr Cardiol. 2019 Dec;40(8):1575-1583. doi: 10.1007/s00246-019-02189-x. Epub 2019 Aug 30. PMID: 31471626 Similar articles   Take Home Points: Newborns with a prenatal diagnosis of congenital heart disease are not at increased risk of acidosis at the time of delivery when compared to gestational age-matched controls. No difference was noticed in the umbilical arterial (UA) pH between those with single ventricle vs two-ventricle disease and those with and without aortic arch obstruction. In pregnancies complicated by congenital heart disease, spontaneous vaginal delivery with prolonged labor seems to impact the fetal outcome as noted by the significant decline in UA pH with increasing duration of labor in this group when compared to other modes such as induced vaginal delivery and C-Section post-labor. Commentary from Dr. Venu Amula (Salt Lake City), section editor of Fetal Cardiology Journal Watch: The American College of Obstetricians and Gynecologists and the American Academy of Pediatrics recommend performing umbilical artery blood acid-base analysis after certain high-risk deliveries in which a fetal metabolic abnormality is suspected to assess fetal well-being. Adams et al conducted this single-center, retrospective observational study to determine if newborns with congenital heart disease are at a higher risk for acidosis at delivery as determined by the umbilical cord blood analysis. The control group included singleton deliveries without CHD matched by date of birth and gestational age. The authors also sought to determine if specific fetal cardiac diagnosis, type, and duration of labor are associated with acidosis. The cases included all forms of complex congenital heart disease. Given the unique physiological challenges faced by single ventricle heart lesions and those with systemic outflow obstruction – the lesions were divided into 4 categories – Single Ventricle lesions with and without aortic arch obstruction, and Biventricular lesions with and without aortic arch obstruction. Class, I was defined as patients with two ventricles without aortic arch obstruction Class II as patients with two ventricles with arch obstruction, Class III as patients with a single ventricle without arch obstruction and Class IV as patients with a single ventricle with arch obstruction. The study cohort consisted of 134 cases with an equal number of gestational and calendar year matched healthy newborns. Overall there was no difference in the median UA pH in the cases with congenital heart disease versus the control group. There was also no difference by physiological class nor by single ventricle vs two ventricle type nor by the presence or absence of aortic arch obstruction. The authors conclude that fetuses with congenital heart disease have well-compensated hemodynamics and inutero oxygen delivery owing to fetoplacental circulation regardless of the subtype of congenital heart disease. They also evaluated the effect of mode of delivery on UA pH and found that in the congenital heart disease group there was a significant decline in the median UA pH with increasing duration of labor in those with spontaneous vaginal delivery when compared to those with induced vaginal and C-Section Post-Labor. However, it is to be noted that even in this group pathological fetal acidemia, a practical pH threshold where neonatal morbidity increases i.e. umbilical artery pH <7, was rare. The study is limited by a sampling bias given no umbilical arterial blood analysis data was present for those with hemodynamically unstable neonates with congenital heart lesions. Maternal characteristics were also not completely matched given the placental health may impact umbilical cord gas analysis even though venous sampling would be more reflective of that. Duration of labor in fetuses with the diagnosis of congenital heart disease planned for spontaneous vaginal delivery may impact the outcome as evidenced by declining UA pH and needs planned perinatal management.      

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Isolated ventricular septal defects demonstrated by fetal echocardiography: prenatal course and postnatal outcome

Isolated ventricular septal defects demonstrated by fetal echocardiography: prenatal course and postnatal outcome. Raucher Sternfeld A, Sheffy A, Tamir A, Mizrachi Y, Assa S, Shohat M, Berger R, Lev D, Gindes L. J Matern Fetal Neonatal Med. 2020 Jan 12:1-5. doi: 10.1080/14767058.2020.1712710. [Epub ahead of print] PMID: 31928261 Similar articles Select item 31940858   Take Home Points: Small muscular VSDs are common in fetal life with almost 50% closing before birth and over 90% closing by 2 years of life Muscular VSDs were not associated with any chromosomal abnormalities or genetic mutations on microarray analysis, but only a small number of patients underwent testing The high incidence and frequency of spontaneous closure along with no genetic abnormality may suggest that the presence of small muscular VSDs may be a delayed physiological process as opposed to something pathologic, but this premise should be studied further Perimembranous VSDs are less likely to close and more likely to be associated with a genetic abnormality Commentary from Dr. Jared Hershenson (Greater Washington DC), section editor of Pediatric Cardiology Journal Watch:  VSDs are the most common congenital cardiac malformation and often diagnosed prenatally. Most VSDs will have little hemodynamic effect prenatally due to equal pressure in both ventricles and limited shunting and many close during fetal life or within a few years after birth. This was a retrospective study looking at prenatal course and postnatal outcomes in fetuses diagnosed with VSDs over a 4 year study period of 7466 fetal echocardiograms. 59 cases of complicated CHD was seen (0.79%). 86 isolated VSDs were diagnosed (1.17%) with 11 cases excluded due to loss of follow up. 64/75 patients had muscular VSDs with a mean size of 1.1 mm and median maximal size of 1 mm. In comparison, perimembranous VSDs had a mean size of 2.5 mm and a median size of 3.5 mm. The authors note that all fetuses with a VSD are referred for genetic consultation at this study center and each family can decide on testing. 19 fetuses subsequently had a karyotype and 4 fetuses had a complete microarray. All fetuses had normal testing except for 1 with Down Syndrome who had a perimembranous VSD. Spontaneous closure occurred in 92% of the muscular VSDs during the study period (up to 2 years) and 48.4% closed before birth. This contrasted with perimembranous VSDs, with 45.5% closing over 2 years and 27% before birth (see Table 1). Amongst all VSDs, those that closed spontaneously were significantly smaller than those that remained open (1.48 +/- 0.68 mm vs. 2.6 +/- 1.25 mm). The authors conclude that muscular VSDs are common, are not associated with chromosomal aberrations, and often close spontaneously. They suggest that the presence of these VSDs may actually represent a delayed physiologic process rather than something pathologic. A significant caveat to this would be that very few patients in their study actually underwent genetic testing (specifically microarray) and it is possible that there may be some genetic mutations that would be associated with VSDs. However, invasive genetic testing such as amniocentesis should likely not be recommended for this patient population. Additionally, the overall number of patients was small and while they mention size as a significant factor for spontaneous closure, nearly all of those patients had muscular VSDs anyway. I do think that this study adds to the objective ability of fetal cardiologists to reassure patients when small muscular VSDs are seen even though most of us have recognized this by experience.  

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Coronary Intimal Thickening Begins in Fetuses and Progresses in Pediatric Population and Adolescents to Atherosclerosis

Coronary Intimal Thickening Begins in Fetuses and Progresses in Pediatric Population and Adolescents to Atherosclerosis. Guerri-Guttenberg R, Castilla R, Cao G, Azzato F, Ambrosio G, Milei J. Angiology. 2020 Jan;71(1):62-69. doi: 10.1177/0003319719849784. Epub 2019 May 14. PMID: 31088126 Similar articles Select item 31475425   Take Home Points: Coronary intimal thickening (IT) can be found in infants, children and adolescents. The prevalence of IT is higher with older age. IT is rarely seen in fetuses, suggesting that it is probably not related to embryological or fetal development. Comment from Dr. Inga Voges (Kiel, Germany), section editor of Fetal Cardiology Journal Watch: In this autopsy study the authors assessed the prevalence of coronary intimal thickening (IT) and types of coronary alterations in 63 hearts from fetuses, infants, older children (1-11 y) and adolescents (11-18 y) without structural heart disease. None of the deaths were related to coronary artery alterations. Histomorphometric and planimetric analyses were performed and maximal intima thickness, media thickness, as well as intima to media ratio were measured. IT was defined as musculoelastic thickening characterized by proliferation of smooth muscle cells, scarce monocytes and lymphocytes embedded by amorphous deposits within the internal elastic membrane and morphologically intact endothelium above the lesion. In addition, immunophenotyping of cells in the vessel wall was performed with monoclonal antibodies against macrophages, smooth muscle cells, transforming growth factor b1 (TGF-b1), apolipoprotein B and endothelial cells. An automated immunohistochemical system was used for stem cells(CD34/CD117), fibroblasts (vimentin), endothelial cells (CD34/vimentin), endothelial cells and monocytes/macrophages (vascular endothelial growth factor), and cellular proliferation (Ki67). In the group of fetuses (n=20) only two cases were found to have IT. In the group of infants (n=18), older children (n=15) and adolescents (n=10) the authors found an increasing frequency of coronary alterations with increasing age (see Table I and figure I). The extent of IT correlated with patient age (see figure 3) but was not related to gender or causes of death. Intimal thickening was more commonly found near bifurcation sites in the left anterior descending coronary artery and in zones free of bifurcation in the right coronary artery. The authors also found that the thicker the intima, the more disrupted the internal elastic membrane. Immunohistochemical studies with a-SMC actin could demonstrate, that in IT, smooth muscle cells lose polarity and orient in a perpendicular manner towards the internal elastic membrane or in a disarranged form. The authors nicely summarize that their results suggest that 1) IT is not a “remnant” of changes derived from embryological development, 2) IT cannot be a consequence of alterations in fetal circulation/oxygenation and 3) the effects of maternal risk factors or other maternal conditions during pregnancy are not evident during fetal life.

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Imaging of the pulmonary vasculature in congenital heart disease without gadolinium contrast: Intraindividual comparison of a novel Compressed SENSE accelerated 3D modified REACT with 4D contrast-enhanced magnetic resonance angiography

Imaging of the pulmonary vasculature in congenital heart disease without gadolinium contrast: Intraindividual comparison of a novel Compressed SENSE accelerated 3D modified REACT with 4D contrast-enhanced magnetic resonance angiography. Pennig L, Wagner A, Weiss K,...

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