Protocols for High-Risk Pregnancies. Группа авторов
for abnormal four‐chamber views actually having cardiac anomalies. Current recommendations from US medical societies, including the American College of Obstetricians and Gynecologists (ACOG), the American Institute of Ultrasound in Medicine (AIUM), and the International Society of Ultrasound in Obstetrics and Gynecology, all call for including outflow tract views in the standard (or so‐called “Level 1”) obstetric scan.
Table 6.1 Indications for fetal echocardiography
| Familial risk factors |
| History of congenital heart disease (CHD) |
| Previous sibling with CHD |
| Paternal CHD |
| Second‐degree relative to fetus with CHD |
| Mendelian syndromes that include congenital heart disease (e.g., Noonan, tuberous sclerosis) |
| Maternal risk factors |
| Congenital heart disease |
| Cardiac teratogen exposure: |
| Lithium carbonate |
| Phenytoin |
| Valproic acid |
| Trimethadione |
| Carbamazepine |
| Isotretinoin |
| Paroxetine |
| Maternal metabolic disorders: |
| Diabetes mellitus |
| Phenylketonuria |
| In vitro fertilization |
| Fetal risk factors |
| Suspected cardiac anomaly |
| Extracardiac anomalies |
| Chromosomal |
| Anatomical |
| Fetal cardiac arrhythmia |
| Irregular rhythm |
| Tachycardia (greater than 200 bpm) in absence of chorioamnionitis |
| Fixed bradycardia |
| Nonimmune hydrops fetalis |
| Lack of reassuring four‐chamber view during basic obstetric scan |
| Monochorionic twins |
| Increased nuchal translucency space at 11–14 weeks of gestation |
Full fetal echocardiography includes obtaining all the views in the fetus routinely obtained in postnatal echocardiography (Table 6.2) using both real‐time gray‐scale and color Doppler imaging. Additionally, spectral Doppler, cardiac biometry, and M‐mode data can be obtained as indicated. Fetal echocardiographers use these latter techniques variably. The two‐dimensional examination should be sufficient to exclude significant heart disease in the vast majority of affected individuals. The more sophisticated studies are especially useful in cases of suspected structural or functional abnormalities.
In a recent Practice Parameter, the AIUM has described required and optional components of the detailed fetal echocardiographic examination, shown in Table 6.3.
Table 6.2 Standard fetal echocardiographic views and what to see
| Four chamber |
| Situs: check fetal position and stomach |
| Axis of heart to the left |
| Intact interventricular septum |
| Atria approximately equal sizes |
| Ventricles approximately equal sizes |
| Free movement of mitral and tricuspid valves |
| Heart occupies about one‐third of chest area |
| Foramen ovale flap (atrial septum primum) visible in left atrium |
| Long‐axis left ventricle |
| Intact interventricular septum |
| Continuity of the ascending aorta with mitral valve posteriorly |
| Interventricular septum anteriorly |
| Short axis of great vessels |
| Vessel exiting the anterior (right) ventricle bifurcates, confirming it is the pulmonary artery |
| Aortic arch |
| Vessel exiting the posterior (left) ventricle arches and has three head vessels, confirming it is the aorta |
| Pulmonary artery–ductus arteriosus |
| Continuity of the ductus arteriosus with the descending aorta |
| Venous connections |
| Superior and inferior vena cavae enter right atrium |
| Pulmonary veins entering left atrium from both right and left lungs |
Table 6.3 AIUM recommended components of detailed fetal echocardiographic exam
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Gray‐scale imaging Four‐chamber view including pulmonary veinsLeft ventricular outflow tractRight ventricular outflow tractBranch pulmonary artery bifurcationThree‐vessel view (including view with PA bifurcation and more superior view with ductal arch)Short‐axis views (“low” for ventricles, “high” for outflow tracts)Long‐axis view (if clinically relevant)Aortic archDuctal archSuperior (SVC) and inferior vena cava (IVC) Color Doppler sonography Systemic veins (including superior and inferior vena cava and ductus venosus)Pulmonary veins (at least two, one right vein and one left vein)Atrial septum and foramen ovaleAtrioventricular valvesVentricular septumSemilunar valvesDuctal archAortic arch Pulsed Doppler sonography Right and left atrioventricular valvesRight and left semilunar valvesPulmonary veins (at least two; one right vein and one left vein)Ductus venosusSuspected structural or flow abnormality on color Doppler sonography Heart rate and rhythm assessmentCardiac biometry (z‐scores recommended) Aortic and pulmonary valve annulus in systole (absolute size with comparison of left‐ to right‐sided valves)Tricuspid and mitral valve annulus in diastole (absolute size with comparison of left‐ to right‐sided valves) Optional biometry Right and left ventricular lengthsAortic arch and isthmus diameter measurements from the sagittal arch view or three vessels and trachea view with comparison of aortic isthmus to ductus |