AbnormalThree-VesselView on Sonography: A Clue to the Diagnosis of Congenital Heart Disease in the Fetus

Transcription

1 rt Pictorial Essay bnormalthree-vesselview on Sonography: Clue to the Diagnosis of Congenital Heart Disease in the Fetus screening tool for major congenital heart diseases [I. 2J. However, anomalies of the ventricular outflow tracts or the great arteries (or both) can be missed by screening with a fourchamber view alone 13-Si- Thus, inclusion of Shi-Joon Yoo3, Young Ho Lee1, Kyoung Sik Cho3 E xamination of the fetal heart with a ventricular outflow tract views in screening fetal four-chamber view is an excellent sonography is advised. However. some researchers believe that the ventricular outflow tracts are difficult to examine 16, 71. The three-vessel view is an orthogonal transverse view of the fetal upper media.stinum, where the main pulmonary artery, ascending B aorta. and superior vena cava are arranged in a straight line and sized in decreasing order 181 (Fig. I). This view can be easily obtained by moving the transducer cephalad from the fourchamber plane, and little time is needed to obtam this view. The three-vessel view provides important clues to the diagnosis of anomalies of Fig. 1.-Normal relationship of three vessels (ascending aorta (l, main pulmonary artery [P1, superior vena cava IV]). a = descending aorta, d ductus arteriosus, c = carina, It = left, rt = right, Diagram of healthy heart seen from front shows normal relationship of main pulmonary artery, ascending aorta, and superior vena cava. Horizontal line indicates level of transverse section shown in B and C. LV = left ventricle, RV = right ventricle. B and C, Diagram of three-vessel view (B) and corresponding sonogram (C) from fetus of 24 weeks gestation. Oblique section of main pulmonary artery and cross sections of ascending aorta and superior vena cava are aligned and sized in decreasing order. Descending aorta is seen on left anterior aspect of spine (S), suggesting left aortic arch. (C reprinted with permission from [81) C Received July io, 1998; accepted after revision September 2, Department of Ultrasound, Samsung Cheil Hospital and Women s Healthcare Center, Sungkyunkwan University, 1-19 Mookjung-dong, Chung-ku, Seoul, , Korea. ddress correspondence to S.-J. Yoo at Department of Diagnostic Imaging, Hospital for Sick Children, University of Toronto, 555 University ve., Toronto, Ontario, M5G ix8, Canada. 2Department of Radiology, Sejong Heart Institute, 91-i2i Sosa-bon 2-dong, Sosa-ku, Puchon, Kyunggi-do, , Korea. 3Department of Diagnostic Radiology, san Medical Center, Ulsan University, 388-i Pungnap-dong, Songpa-ku, Seoul, , Korea. JR i999;i72: O36i-803X/99/i merican Roentgen Ray Society JR:172, March

2 Yoo et al. Fig. 2.-Relationship of three vessels (ascending aorta [], main pulmonary artery [P], superior vena cava [VI) in tetralogy of Fallot. a = descending aorta, It = left, rt = right, Diagram of heart with tetralogy of Fallot seen from front shows abnormal relationship of dilated ascending aorta and small main pulmonary artery. Horizontal line mdicates level of transverse section shown in B and C. LV = left ventricle, RV = right ventricle, d = ductus arteriosus. B and C, Diagram of three-vessel view (B) and corresponding sonogram (C) from fetus of 25 weeks gestation show anterior displacement of large ascending aorta and posterior displacement of small main pulmonary artery. c = carina, S = spine. the ventricular outflow tracts or the great arteries (or both) because most of them show abnormal size, position, or relationship between the ascending aorta and main pulmonary artery, as illustrated in Figures 2-4. This view also provides clues to the diagnosis of abnormalities of the superior vena cava. Because the anatomy seen on the three-vessel view is simple, subtle distortion of vessel alignment, arrangement, or size is readily discernible. This pictorial essay illustrates the abnormalities seen on the threevessel view in fetuses with various fetal congenital heart diseases. The abnormalities shown were proven by postnatal echocardiography or by autopsy after termination of pregnancy in all cases except one. bnormal Vessel Size Usually the size of the vessel reflects the amount of blood flow passing through it. Thus, a reciprocal relationship exists between the size of the ascending aorta and that of the main B pulmonary artery. small ascending aorta and large main pulmonary artery suggest diversion of the blood flow from the left to the right side of the heart. Preferential flow into the right heart occurs when an obstructive lesion or lesions exist in the left heart, such as diminutive foramen ovale, dividing membrane within the left atrium, mitral stenosis or atresia, and left ventricular outflow tract obstruction. These lesions are characterized by a variable degree of hypoplasia of the left heart or obstructive le- C Fig. 3.-Relationship of three vessels (ascending aorta [], main pulmonary artery [P1, superior vena cava [VI) in complete transposition of great arteries. a = descending aorta, d = ductus arteriosus, It = left, rt = right., Diagram of heart with complete transposition seen from front shows that ascending aorta is located to right and anterior to main pulmonary artery and to left and anterior to superior vena cava. Horizontal line indicates level of transverse section shown in B and C. LV = left ventricle, RV = right ventricle. B and C, Diagram of three-vessel view (B) and corresponding sonogram (C) from fetus of 20 weeks gestation show gross distortion of three-vessel alignment. scending aorta is located to right and anterior to main pulmonary artery. S = spine. 826 JR:172, March 1999

3 Sonography of Fetal Congenital Heart Disease -- 1., rt Fig. 4.-Relationship of three vessels (ascending aorta [l, main pulmonary artery [P1, superior vena cava [VI) in corrected transposition of great arteries. a = descending aorta, LV = left ventricle, RV = right ventricle, It = left, rt = right., Diagram of heart with corrected transposition seen from front shows that ascending aorta is located to left and anterior to main pulmonary artery. Horizontal line mdicates level of transverse section shown in B and C. B and C, Diagram of three-vessel view (B) and corresponding sonogram (C) from fetus of 22 weeks gestation show that positions of ascending aorta and main pulmonary artery are reversed compared with normal positions. d = ductus arteriosus, S = spine. sion of the aortic arch (or both) (Fig. 5). Preferential flow into the right heart also occurs when an anomalous pulmonary venous connection exists and when the blood flow through the tricuspid valve is increased because of an unknown cause. small main pulmonary artery and large ascending aorta suggest diversion of the blood flow from the right to the left side of the heart. Preferential flow into the left heart occurs with tricuspid stenosis, tricuspid regurgitation, and an obstructive lesion within the right ventricle. Ebstein s anomaly is the most common tricuspid valve lesion that shows a small main pulmonary artery because oftricuspid regurgitation (Fig. 6). The main pulmonary artery is characteristically small in tetralogy of Fallot. In pulmonary atresia with an intact ventricular septum, the main pulmonary artery may be normal in size or small. Isolated dilatation of the ascending aorta occurs with aortic valve stenosis because of thejet flow through the stenotic valve (Fig. 7). By the same token, isolated dilatation of the main pulmonary artery occurs with pulmonary valve stenosis (Fig. 8). Dilatation of the B great artery may also occur with valvar regurgitation. Dilatation of the ascending aorta and aortic sinus of Valsalva may be a feature of fetal Marfan syndrome. Dilatation of the superior vena cava occurs when there is an interruption of the inferior vena cava with azygos or hemiazygos continuation or when there is right heart failure. bnormal Vessel lignment bnormal alignment is a condition in which the three vessels are not aligned in a straight line, but their overall left-right order is preserved., - -:. ;;:.:....., ; #{149},-. 1 Fig. 5.-Fetus of22 weeks gestation with severe tubular hypoplasia ofaortic arch and Fig. 6.-Fetus of 22 weeks gestation with Ebstein s anomaly of tricuspid valve. ventricular septal defect Three-vessel view on sonography shows small ascending Three-vessel view on sonography shows that main pulmonary artery (P) is smaller aorta () with size resembling that of superior vena cava (V). Main pulmonary artery than ascending aorta (). a = descending aorta, d = ductus arteriosus, It = left, rt = (P) is enlarged. Note minimal distortion of three-vessel alignment a = descending right, S = spine, v = superior vena cava. aorta, d = ductus arteriosus, It = left, rt = right, S = spine. JR:172, March

4 Yoo et al. :; $ :.*,., : a.; : r+ Fig. 1.-Fetus of 31 weeks gestation with aortic valve stenosis and bilateral supenor venae cavae. Three-vessel view on sonography shows that ascending aorta () is enlarged because of poststenotic dilatation. Right superior vena cava (v) is small. Note additional superior vena cava (v*) on left side. P = main pulmonary artery, It = left, rt = right, S = spine. (Reprinted with permission from [8]) bnormal alignment is more commonly caused by anterior displacement of the ascending aorta with or without posterior displacement of the main pulmonary artery. This form of abnormal alignment is seen in most cases of tetralogy of Fallot in which the dilated ascending aorta is displaced anteriorly and the small main pulmonary artery is displaced posteriorly (Fig. 2). It is also seen in double-outlet right ventricle in which the great arteries are commonly located side-by-side (Fig. 9). Occasional cases of complete transposition of the great arteries may show a similar arterial relationship. Fig. 8.-Fetus of 27 weeks gestation with pulmonary valve stenosis. Three-vessel view on sonography shows that main pulmonary artery (P) is enlarged because of poststenotic dilatation. = ascending aorta, a = descending aorta, It = left, rt = right, S = spine, v = superior vena cava. Less commonly, abnormal alignment is caused by posterior displacement of the ascending aorta. This displacement suggests a severe form of left-sided obstructive lesion, such as hypopla.stic left heart syndrome (Fig. 10) and interruption ofthe aortic arch. bnormal Vessel rrangement bnormal arrangement is a condition in which the left-right order of the three vessels is grossly distorted. When the ascending aorta is located to the right and anterior or directly anterior to the r. -..I main pulmonary artery, the three vessels are aligned in a triangle. This arrangement is most commonly seen in complete transposition of the great arteries (Fig. 3) and is less commonly seen in double-outlet right ventricle. Location of the ascending aorta to the left and anterior to the main pulmonary artery strongly suggests corrected transposition of the great arteries (Fig. 4). similar arterial relationship also occurs in cases ofdouble-inlet left ventricle and transposition. Rarely, the superior vena cava is missing on the right but is present on the left side (Fig. 1 1).. : : -!. ==. Fig. 9.-Fetus of 23 weeks gestation with double-outlet right ventricle. Three-vessel Fig. 10.-Fetus of 33 weeks gestation with hypoplastic left heart syndrome caused view on sonography shows that ascending aorta () and main pulmonary artery (P) by mitral and aortic atresia. Three-vessel view on sonography shows that ascendhave side-by-side relationship. It = left, rt = right, S = spine, v = superior vena cava. ing aorta () is tiny and is displaced posteriorly. Main pulmonary artery (P) is markedly dilated. It = left, rt = right, S = spine, v = superior vena cava. 828 JR:172, March 1999

5 Sonography of Fetal Congenital Heart Disease Ii_._---_ -:- c.._ - -, T7:T,.., Fig. 11.-Fetus of 20 weeks gestation with persistence of left superior vena cava and absence of right superior vena cava. Three-vessel view on sonography shows that superior vena cava (v) is seen on left side of small pulmonary artery (P). rrow mdicates tip of left atrial appendage. = ascending aorta, a = descending aorta, It = left, rt = right, S = spine. bnormal Vessel Number The three-vessel view shows only two yessels in truncus arteriosus, which is characterized by a single arterial trunk that gives rise to the aorta and pulmonary artery (Fig. 12). Only two vessels can be seen also in pulmonary atresia with a ventricular septal defect when the main pulmonary artery is atretic or absent. Four vessels are seen when bilateral superior venae cavae are present (Figs. 7 and I 3). In late gestation, the ductus may become tortuous and its cross section may be seen as an additional vessel at the left posterior aspect of the main pulmonary artery (Fig. 14). bnormal Location of Descending orta The descending aorta is seen normally in the posterior mediastinum at the left anterior corner of the spine. When the descending aorta Fig. 12.-Fetus of 34 weeks gestation with truncus arteriosus. Three-vessel view on sonography shows only two vessels: superior vena cava (v) on right (rt) and common arterial trunk (Tr) on left (It). a = descending aorta, S = spine. is seen on the right, this location is strongly suggestive of right aortic arch (Fig. I 5). The descending aorta may be located on the right, on the left, or in the midline when a double aortic arch exists. cknowledgment We thank Eul Kyung Kim for making the illustrations. Fig. 13.-Fetus of2oweeks gestation with bilateral superiorvenae cavae. Three-vessel Fig. 14.-Fetus of 35 weeks gestation with tortuous ductus arteriosus. Three-vessel view on sonography shows four vessels. Normal right superior vena cava (v) is small. view on sonography shows tortuous ductus arteriosus (d), which forms vascular loop at dditional vessel, persistent left superior vena cava (v*), is seen at left posterior aspect left posterior aspect of main pulmonary artery (P) and should not be mistaken for abnorof main pulmonary artery (P). = ascending aorta, a = descending aorta, It = left, rt = mal additional vessel. = ascending aorta, a = descending aorta, It = left, rt = right, S = right, S = spine. spine, v = superior vena cava. JR:172, March

6 Yoo et al. References 1. Copel J, Pilu G, Green J, Hobbins JC, Kleinman CS. Fetal echocardiographic screening for congeniwl heart disease: the importance of the four-chamber view. m J Obstet Gvnecol 1987:157: Fig. 15.-Fetus of 30 weeks gestation with tetralogy of Fallot and right aortic arch. Threevessel view on sonography shows descending aorta (a) at right anterior aspect of spine (S). Note abnormal vessel alignment and small main pulmonary artery (P) that are characteristic oftetralogy offallot = ascending aorta, It = left, rt = right, v = superior vena cava. 2. McGahan JP. Sonography of the fetal heart: findings on the four-chamber view. ir 1991:156: Bromley B, Estroff J, Sanders SP, et al. Fetal echocardiography: accuracy and limitations in a population at high and low risk for heart defects. m J Obstet Gvnecol 1992; 166: Sharland GK, llan LD. Screening for congenital heart disease prenatally: results of a 2 and 1/2- year study in the South East Thames region. Br J Obstet Gvnaeeol 1992;99: Benacerraf BR. Sonographic detection of fetal anomalies of the aortic and pulmonary arteries: value of four-chamber view vs direct images. ir 1994; 163: Wigton TR, Sabbagha RE, Tamura RK, Cohen L, Minogue JP, Strasburger if. Sonographic diagnosis of congenital heart disease: comparison between the four-chamber view and multiple views. Obstet Ginecol 1993:82: Rustico M. Benettoni, D Ottavio G, et al. Fetal heart screening in low-risk pregnancies. Ultrasound Obstet Gwzeol 1995:6: Yoo S-J, Lee Y-H, Kim E-S, et al. Three-vessel view ofthe fetal upper mediastinum: an easy means of detecting abnormalities of the stntricular outflow tracts and great arteries during obstetric screening. Ultrasound Obstet Gynecol 1997:9: JR:172, March 1999