Impact of Transcatheter Occlusion of a Patent Ductus Arteriosus on Atrial Septal Defect Diameter in Children

Background. A persistent patent ductus arteriosus (PDA) may delay closure of a coexisting atrial septal defect (ASD) due to volume loading and enlargement of the left atrium. The purpose of this study was to investigate the natural history of ASD size in patients with a PDA following transcatheter PDA occlusion. Methods. All patients with an ASD and a PDA who underwent transcatheter PDA occlusion at Texas Children’s Hospital were identified. Patients with ASD diameter <3 mm, or additional cardiac defects were excluded. Eight patients (7 females) with small‐ to moderate‐sized ASDs and a PDA were identified. Patient demographics, echocardiographic data, and cardiac catheterization data were recorded. Data were analyzed by 1‐tailed t‐test. Results. Following PDA occlusion, ASD diameter decreased in 6 of 8 patients by a mean of 3.8 mm (±2.3 mm), including 2 that closed. The median duration of follow‐up was 689 days. One ASD remained unchanged and 1 increased in size. The mean maximum ASD diameter decreased from 6.4 mm (±2.2 mm) to 3.9 mm (±3.4 mm) (P = .03). Two patients underwent subsequent transcatheter ASD occlusion. Conclusion. Following transcatheter PDA occlusion, small‐ to moderate‐sized ASDs have significant probability to decrease in size, and possibly close. In infants and children, we recommend transcatheter PDA occlusion, and serial follow‐up of the size of the ASD. This will allow many small‐ to moderate‐sized ASDs to either close, or become smaller, obviating the need for future intervention.     

In normal development pulmonary veins are connected to the sinus venosus segment in the left atrium

Background: Classic theories descibe that the common pulmonary vein develops as an outgrowth from either the sinus venosus or atrial segment. Recent studies show that the pulmonary veins are connected to the sinu-atrial region before its differentiation into a sinus venosus and atrial segment. Methods: The development of the sinu-atrial region with regard to the developing common pulmonary vein and the growth of the atrial septum was investigated in avian embryos, using both scanning electron microscopy and immunohistochemistry. Embryos ranging between stage HH12 and HH28 were incubated with QH-1 that recognizes quail endothelial cells and precursors, HNK-1, that appears in this study to detect the myocardium of the sinus venosus, or with HHF-35, being specific for muscle actins. Also vascular casts of the heart were produced by injecting prepolymerized Mercox into the vascular system. Results: In preseptation stages the common pulmonary vein drains into the left part of the sinus venosus, that is clearly demarcated by the sinuatrial fold and HNK-1 expression. During atrial septation the left part of the sinus venosus, in contrast to the right part, loses its HNK-1 antigen from stage HH23 onwards, while at the same time the sinu-atrial fold in the left atrial dorsal wall flattens and disappears. From stage HH25 onwards HNK-1 expression is restricted to the right part of the sinus venosus, which contributes to the right atrium. The myocardial atrial septum never expresses the HNK-1 antigen, suggesting that the septum is of atrial origin. Discussion: It appeared that the sinus venosus does not only contribute to the sinus venarum of the right atrium, but also to the left atrium. © 1995 Wiley-Liss, Inc.     

Morphometric study of the ductus arteriosus during human development

During prenatal life, the ductus arteriosus connects the left pulmonary artery and the descending aorta. Morphometric features (length, external diameter, volume) of the ductus arteriosus in 131 human fetuses (65 males, 66 females) were studied by means of anatomical, digital and statistical methods. Regression analysis was used to investigate the growth of the ductus arteriosus during gestation. The values of the length of the ductus arteriosus ranged from 3.95 mm for the 15 week gestational group to 12.20 mm for the 34th week of gestation. The length of the ductus arteriosus related to fetal age (x) increased according to the linear function y = -3.0726 + 0.4381x. The mean values of the diameter of the ductus arteriosus ranged from 1.34 to 3.49mm for the 15 and 34 week gestational groups, respectively. The growth of the ductus arteriosus diameter followed in accordance with the linear function y = 0.2072 + 0.0935x. The mean values of the ductus arteriosus volume ranged from 5.08 mm3 for the 15 week group to 117.30 mm3 of the 34 week gestation group. The volume growth increased according to the function y = 0.0007x3.3782. Positive correlation coefficients between arterial parameters and fetal age were statistically significant (P < or = 0.01) and reached the following values: r1 = 0.98 for Length, r2 = 0.90 for diameter and r3 = 0.94 for volume. Despite the increase in absolute diameter, the relative diameter of the ductus arteriosus (ductus arteriosus-to-aortic bulb diameter ratio) decreased from 0.80 to 0.48.     

Coarctation of the Left Pulmonary Artery: Effects on the Pulmonary Vasculature of Infants

At autopsy, two infants had unsuspected coarctation of the left pulmonary artery (CoLPA), which was produced by an extension of ductal tissue into the wall of the left pulmonary artery. The first case, a 4-month-old girl, also had a ventricular septal defect and an anomalous branching pattern of the innominate arterial trunk. Pulmonary arterial hypertensive changes were noted in the right lung. In contrast, the left lung showed thin-walled pulmonary arteries. The second case, a term female newborn, had exhibited severe unexplained respiratory distress since birth. Histologic sections of the right lung showed dilated pulmonary arteries with thinned media, whereas the left lung showed a persistent fetal arterial pattern. It is believed that the peripheral pulmonary arterial changes are age-dependent and associated with asymmetric blood flow between the right and left pulmonary arteries. CoLPA is a rare pulmonary artery defect, and early diagnosis of this abnormality is important.     

Ultrasonographic study of ductus venosus in healthy neonates

AIM—To assess ultrasonographically the flow pattern and the time of postnatal closure of ductus venosus related to the other fetal shunts.
METHODS—Fifty healthy, term neonates were studied from day 1 up to day 18 using a VingMed CFM 800A ultrasound scanner.
RESULTS—Ductus arteriosus was closed in 94% of the infants before day 3. Ductus venosus, however, was closed in only 12% at the same time, in 76% before day 7, and in all infants before day 18. A closed ductus venosus or ductus arteriosus did not show signs of reopening. Pulsed and colour Doppler flow could be detected across the foramen ovale in all infants during the sequential investigation. At day 1, when the pulmonary vascular resistance was still high, a reversed Doppler flow velocity signal was seen in ductus venosus in 10 infants (20%) and a bidirectional flow in ductus arteriosus in 26 (52%). Closure of the ductus venosus was not significantly correlated with closure of the ductus arteriosus nor related to sex nor weight loss.
CONCLUSIONS—The time of closure of the ductus venosus evaluated by ultrasonography is much later than that of the ductus arteriosus. The flow pattern in ductus venosus reflects the portocaval pressure gradient and the pressure on the right side of the heart and in the pulmonary arteries. Both the flow pattern in the ductus venosus as well as that in the ductus arteriosus may be an indication of compromised neonatal haemodynamics.

     

Aortic Stenosis and Patent Ductus Arteriosus: Pressure Gradients Pre- and Posttranscatheter Ductal Occlusion

Three patients with patent ductus arteriosus and moderate aortic stenosis had a marked reduction in aortic valve gradient following transcatheter ductal occlusion. The hemodynamic effects of an aortopulmonary shunt on the severity of left ventricular outflow obstruction and the implications on intervention are discussed.     

应用可回收与非回收弹簧圈装置堵塞动脉导管未闭的比较

目的比较应用可回收（ｄｅｔａｃｈａｂｌｅｃｏｉｌ）与非回收弹簧圈（ｎｏｎｄｅｔａｃｈａｂｌｅｃｏｉｌ）堵塞动脉导管未闭（ＰＤＡ）的效果，并探讨影响效果的因素。方法经导管堵塞１８例ＰＤＡ患儿，男４例，女１４例；年龄３～１２岁。ＰＤＡ最狭窄处直径为１．２～３．６ｍｍ（平均２．３ｍｍ）。其中３例ＰＤＡ外科结扎后再通，１例ＰＤＡ伴肺动脉瓣狭窄。结果１８例患儿中７例应用非回收弹簧圈堵塞法，其中５例获成功；１１例应用可回收弹簧圈装置，堵塞均获成功，其中９例应用双圆锥形弹簧圈，另２例采用Ｃｏｏｋ可回收弹簧圈。彩色多普勒显示９例堵塞术２４小时后无分流，２例随访发现极少量分流。结论应用可回收弹簧圈堵塞ＰＤＡ，其效果优于非回收弹簧圈；可适用未经手术及外科结扎后再通的ＰＤＡ患儿。该法简便、有效、安全、并发症少，为堵塞中小型（直径≤３．５ｍｍ）ＰＤＡ值得推荐的方法     

正常及右位心胎儿的静脉导管超声多普勒血流波形变化

目的探讨胎儿静脉导管(DV)超声波血流波形随孕周变化的规律,检查右位心胎儿DV波形并随访其妊娠结局。方法采用Acuson128xp/10彩色多普勒超声仪测定142名正常妊娠日本妇女胎儿DV多普勒血流阻力指数(DV-RI),随访1例右位心胎儿DV超声多普勒血流波形变化及分娩结局。结果DV-RI与孕周呈负相关(r=-0．247,P=0．003 3)。右位心胎儿DV多普勒血流波形的心房收缩波近缺失。结论随孕周增加,DV-RI呈下降趋势。DV多普勒血流波形心房收缩波形缺失提示心脏前负荷增加、右心功能不良。     

Does first-trimester nuchal cord affect the blood flow in the ductus venosus? A prospective observational study

Introduction: Main objective of the present study was to investigate the association between the presence of nuchal cord (NC) and the measurement of the ductus venosus pulsatility index for veins (ductus venosus (DV) PIV).

Methods: This was a prospective study of 1974 singleton pregnancies that underwent first-trimester screening at 11–13⁺⁶ gestational weeks. Color Doppler was used to demonstrate the presence of a NC in all cases and the DV PIV was calculated routinely, as part of the standard scan. The association between the presence of a NC and the DV PIV was then examined overall and at each gestational week.

Results: A NC was demonstrated in 17.1% of cases. The incidence of nuchal cord was significantly higher at 13–13⁺⁶ weeks (24.7%, n?=?119) compared to the one at 12–12⁺⁶ (16.5%, n?=?192) and 11–11⁺⁶ weeks (7.9%, n?=?26) (p?p?=?.344). The DV PIV was 0.99 (± 0.15) for patients without NC versus 0.99 (± 0.15) for patients with NC (p?=?.34).

Conclusions: There was no association between the presence of a NC at 11–13⁺⁶ gestational weeks and the DV PIV.     

Umbilical artery Doppler velocimetry in normal pregnancies from 11+0 to 13+6 gestational weeks: A Taiwanese study

ObjectiveThe aim of this study is to investigate the relationship between umbilical artery flow and gestational age (GA) at 11–13⁺⁶ weeks in normal pregnancy in the Taiwanese population.Materials and methodsTwo hundred and fifty-three normal singleton pregnancies with GA ranging from 11 to 13⁺⁶ weeks were included in this study. The velocity of systolic, diastolic, and pulsatility index (PI) of the umbilical artery, and the mean velocity of the umbilical vein were recorded.ResultsOne hundred and eighty-seven participants fulfilling the inclusion and exclusion criteria were analyzed. The mean maternal age was 31 (range 19–45) years, with a corresponding GA of 12⁺⁴ (range 11–13⁺⁶) weeks. The absence of end-diastolic velocity of the umbilical artery was observed in most of our cases (90.1%). No significant change was found in the vascular indices with GA for the mean velocity of the umbilical vein (mean velocity = 0.923 × GA − 1.594, r = 0.1497, p = 0.115). The systolic velocity of the umbilical artery and PI, however, behaved differently from the other variables. There was a significant increase in systolic velocity with GA [systolic wave (S wave) velocity = 0.237 × GA + 2.267; r = 0.149, p = 0.041]. By contrast, the PI showed a significant decrease in relation to the GA (PI = −0.016 × GA + 4.068; r = 0.196, p = 0.007).ConclusionThe S-wave velocity of the umbilical artery increased with GA. By contrast, the PI of the umbilical artery showed a decreasing trend with GA. This may ensure optimal placental perfusion, which is necessary to accommodate the increased blood flow to the developing fetus. Furthermore, an absence of end-diastolic velocity in the first trimester and early second trimester was usually seen.