Sensitivity and Specificity of Prenatal Features of Physiological Shunts to Predict Neonatal Clinical Status in Transposition of the Great Arteries

Abstract

Background-Although prenatal diagnosis of transposition of the great arteries (TGA) reduces neonatal mortality, the preoperative course can be complicated in infants with a restrictive foramen ovale (FO) or a ductus arteriosus (DA) constriction. We sought to determine the specificity and sensitivity of prenatal features of physiological shunts in predicting postnatal clinical status in prenatally diagnosed TGA in babies delivered in a tertiary care center providing all facilities for neonatal urgent care. Methods and Results-The outcomes of 130 fetuses with TGA were reviewed over a period of 5.5 years. Restriction of the FO and/or constriction of the DA could be analyzed in 119/130 fetuses at 36Ϯ2.7 weeks of gestation. Twenty-four out of 119 had at least 1 abnormal shunt (23 FO, 5 DA, and 4 both). Thirteen of 130 neonates had profound hypoxemia (PaO 2 Ͻ25 mm Hg) and metabolic acidosis (pH Ͻ7.15) in the first 30 minutes and required immediate balloon atrioseptostomy. Two who had abnormal FO and DA died despite aggressive resuscitation. The specificity and sensitivity of the fetal echo in predicting neonatal emergency were 84% and 54%, respectively. The specificity and sensitivity of a combination of restrictive FO and DA constriction were 100% and 31%, respectively. Conclusions-Restriction of the FO and/or of the DA has a high specificity to predict the need for emergency neonatal care in fetuses with TGA, but the sensitivity is too low to detect all high-risk fetuses. Exceptional procedures should be considered for fetuses that have a combination of restrictive FO and DA constriction. Key Words: heart defects, congenital Ⅲ transposition of great vessels Ⅲ echocardiography P renatal detection of transposition of the great arteries (TGA) has been well established. [1][2][3][4] Of those neonates admitted with TGA, mortality is estimated around 4% and is mostly due to inadequate interatrial mixing despite prostaglandin E1 infusion. 5 We have previously reported that prenatal diagnosis of TGA reduced neonatal mortality and morbidity. 3 However, early demise of neonates with TGA has been reported even after a prenatal diagnosis, suggesting that there was no site available for mixing immediately after birth. 3,[5][6][7][8] Indeed, antenatal restriction of the foramen ovale and/or the ductus arteriosus were found predictive of significant neonatal morbidity and mortality. 9 Because the surgical mortality for the arterial switch operation is as low as 2% in many institutions, 10 -13 the preoperative mortality is a major issue in the management and outcome of infants with TGA. Here, we reviewed the prenatal features of the foramen ovale and of the ductus arteriosus in all our cases of prenatally diagnosed TGA to address the relation between prenatal echo features and need for urgent intervention. Methods PopulationOne hundred thirty consecutive patients with a prenatal diagnosis of TGA were identified over a period of 5.5 years (November 1, 1997 to February 28, 2003. TGA was suspected during routine prenatal ultrasonogra...

Diagnosis and Treatment of Fetal Cardiac Disease

“…Management of these fetuses, who are at significant risk of compromise with foramen ovale restriction or closure, can benefit from coordination of care in the delivery room. 175,176,481,547,572,584,585,[588][589][590][591][592][593][594] Fetuses with HLHS identified to have a severely restrictive or intact atrial septum are at increased risk for compromise in the delivery room if fetal pulmonary vein flow shows significant reversed flow suggesting severe left atrial hypertension in the third trimester. 175,176,481,549,572 In 2 studies, 176,481 the ratio of pulmonary vein forward to reversed velocity-time integral was used to determine potential need for intervention.…”

“…Fetal echocardiogram features that predict the risk of postnatal closure of the foramen ovale by assessing the anatomy and flow across both the foramen ovale and ductus arteriosus have been reported. 547,585,588,591,592 The foramen ovale was found to be at risk for closure in 1 study 585 if the angle of septum primum was <30° to the atrial septum, if there was bowing of the septum primum into the left atrium >50%, or if there was a lack of normal swinging motion of the septum primum. In another study, 547 a hypermobile septum primum, especially in the presence of an abnormal ductus arteriosus, was shown to be predictive of compromise.…”

“…IIa/B d-TGA Reported FO findings predictive of restriction: Angle of septum primum <30° to the atrial septum 585 Bowing of septum primum into the left atrium >50% 585 Lack of normal swinging motion of septum primum 585 Hypermobile septum primum 547 (Note: all fetuses with d-TGA and concerning septum primum should be considered at risk CHB indicates complete heart block; COR, classification of recommendation; CVP, cardiovascular profile; d-TGA, transposition of the great arteries; DA, ductus arteriosus; ECMO, extracorporeal membrane oxygenation; EFE, endocardial fibroelastosis; FO, foramen ovale; HLHS, hypoplastic left heart syndrome; IAS, intact atrial septum; ICU, intensive care unit; LOE, level of evidence; MRI, magnetic resonance imaging; RFO, restrictive foramen ovale; TAPVR, total anomalous pulmonary venous return; and TOF with APV, tetralogy of Fallot with absent pulmonary valve.…”

Aortopulmonary Transposition in the Fetus: Speculation on Pathophysiology and Therapy

“…At that time it was not possible to examine the fetus in utero. However, with the advent of ultrasonography, two reports have described the presence of abnormalities of the foramen ovale and/or the ductus arteriosus in some fetuses with aortopulmonary transposition (2,3). The possible role of increased pulmonary arterial oxygen saturation in causing these changes was reiterated (2).…”

Early discontinuation of intravenous prostaglandin E1 after balloon atrial septostomy is associated with an increased risk of rebound hypoxemia

“…This association has been supported by studies showing improved stability in extremely hypoxemic infants with the use of iNO. 14,15 Premature closure of the foramen ovale and/or ductus arteriosus also has been shown to be associated with severe postnatal hypoxemia [16][17][18] and pulmonary hypertension, thought to occur as a result of pulmonary vascular remodeling. 18 The rationale to discontinue the PGE 1 infusion is based on a theoretical risk that if the left ventricle (LV) is exposed to a lower PVR preoperatively, it is less likely to adapt to the sudden increase in LV afterload that occurs following the arterial switch procedure.…”