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Clinical and ultrasonographic features of dextroposition of the fetal heart
Clinical and ultrasonographic features of dextroposition of the fetal heart Adam F. Borgida, MD, Anthony Odibo, MB, BS, James F.X. Egan, MD, Danielle Esters, MD, and Winston A. Campbell, MD Farmington and Hartford, Connecticut OBJECTIVE: Our purpose was to characterize the findings associated with dextroposition of the fetal heart. STUDY DESIGN: A fetal echocardiography database was retrospectively searched from January 1990 through December 1996 to identify all cases referred or diagnosed with dextroposition of the fetal heart. Dextroposition was defined as most of the normally connected fetal heart found on the right side of the fetal chest. Intracardiac and extracardiac fetal anomalies were reviewed. All available karyotypes and postnatal examinations were reviewed. RESULTS: During the study period 2882 fetal echocardiograms were performed, of which 297 (10.3%) were abnormal. Of these, 14 had dextroposition. Associated anomalies included atrioventricular canal (29%), diaphragmatic hernia (21%), and aneuploidy (14%). Isolated dextroposition with no other significant anomalies was seen in only 1 case. In another, no anomalies were noted except for suspected agenesis of 1 lobe of the right lung; karyotype and postnatal evaluation revealed no other abnormalities in both cases. CONCLUSIONS: Dextroposition of the fetal heart was seen in 0.5% of our fetal echocardiograms and was associated with significant anomalies in 86% of our cases. When diagnosed, a targeted ultrasonogram, fetal echocardiogram, and karyotype should be offered. (Am J Obstet Gynecol 1998;179:982-4.)
Key words: Fetal echocardiogram, congenital heart disease, dextroposition
Fetal echocardiography will diagnose congenital heart disease in the antepartum period in 40% to 85% of cases.1-3 A four-chamber view is an essential part of a fetal ultrasonogram and has been reported to be a useful screening tool for detecting congenital heart disease.4 The axis of the fetal heart in the chest has also been reported to be useful in screening for congenital heart disease.5, 7 When the fetal heart is displaced from the normal position in the chest, intracardiac and extracardiac fetal anomalies may be present. The purpose of this study was to evaluate the associated anomalies in cases of dextroposition of the fetal heart detected at the time of fetal echocardiogram.
Francis Hospital and Medical Center. Both institutions are tertiary level referral centers for prenatal diagnosis. For the purposes of this study, dextroposition of the fetal heart was defined as most of a normally connected fetal heart found on the right side of the fetal chest (Fig 1). True dextrocardia, situs inversus in the thorax, was an exclusion for the study. Intracardiac and extracardiac fetal anomalies were reviewed from patient reports and by reviewing ultrasonograms. All available karyotypes and postnatal examinations were reviewed. Data were analyzed using descriptive statistics. Results
Methods Our fetal echocardiography database was retrospectively searched from January 1990 through December 1996 to identify all cases referred or diagnosed with dextroposition of the fetal heart. The database is maintained by the Divisions of Maternal-Fetal Medicine at the University of Connecticut Health Center and Saint
From the Departments of Obstetrics and Gynecology, University of Connecticut School of Medicine, and Saint Francis Hospital and Medical Center. Presented at the Eighteenth Annual Meeting of the Society of Perinatal Obstetricians, Miami Beach, Florida, February 2-7, 1998. Reprints not available from the authors. Copyright © 1998 by Mosby, Inc. 0002-9378/98 $5.00 + 0 6/6/92572
982
During the study period 2882 fetal echocardiograms were performed with a mean gestational age of 25.3 weeks. Sixty percent of the fetal echocardiograms were performed at the University of Connecticut (1734 of 2882), the remainder were performed at Saint Francis Hospital and Medical Center. Fourteen cases of dextroposition were identified (0.5%); 9 cases were identified at the University of Connecticut and 5 cases at Saint Francis Hospital and Medical Center. The referral indications for all the fetal echocardiograms performed during the study period are shown in Table I. Intracardiac anomalies were noted in 9 of 14 (64%) cases, whereas extracardiac anomalies were noted in 6 of 14 (43%) cases. Fetal karyotype was available in 11 of 14 (79%) cases. An abnormal karyotype was found in 2
Borgida et al 983
Volume 179, Number 4 Am J Obstet Gynecol
Table I. Indications for fetal echocardiogram in study population (N = 2882) Reason
No.
%
Family history of congenital heart disease Diabetes mellitus Dysrhythmia Medication exposure Suspected congenital heart disease Advanced maternal age Fetal anomalies Chromosomal anomalies Other
605
21
432 318 317 260
15 11 11 9
258 202 87 403
9 7 3 14
Fig 1. Four-chamber view of dextroposition of fetal heart.
Table II. Findings in study cases Case No.
Gestational age (wk)
Referral diagnosis
Intracardiac findings
Extracardiac findings
1 2 3 4 5 6 7 8 9 10 11 12 13 14
21.7 19.1 25.7 25.0 34.9 21.7 32.7 30.3 20.6 19.0 20.5 20.4 23.6 20.1
Advanced maternal age Diabetes Fetal anomaly Dysrhythmia Cardiac position Fetal anomaly Fetal anomaly Fetal anomaly Diabetes Cardiac position Cardiac position Advanced maternal age Diabetes Cardiac position
AV canal HPLH VSD AV canal AV canal None None None VSD transposition None None HPLH AV canal VSD
Trisomy 18, hydrocephalus None Hydrocephalus, multiple defects None None CCAML type II Diaphragmatic hernia Diaphragmatic hernia Diaphragmatic hernia None Absent lower lobe right lung Translocation X, 19 None None
AV, Atrioventricular; HPLH, hypoplastic left heart; VSD, ventriculoseptal defect; CCAML, congenital cystic adenomatoid malformation of the lung.
(14%) cases. The cases are summarized in Table II. The most common intracardiac anomaly was an atrioventricular canal defect noted in 29% of cases. Congenital diaphragmatic hernia was the most common extracardiac defect noted in 21% of cases. All the congenital diaphragmatic hernias (cases 7, 8, and 9) were left sided as was the 1 case of congenital cystic adenomatoid malformation of the lung (case 6). There were multiple ultrasonographically detected findings in the 1 case of trisomy 18 (case 1). These included choroid plexus cysts, hypotelorism, micrognathia, hand clenching, and rocker bottom feet. In the other chromosomally abnormal case (case 12) hypoplastic left heart syndrome was the only ultrasonographic finding. Overall, 13 of 14 (86%) cases had major associated congenital anomalies that were confirmed by postnatal examination or autopsy. In one case (case 11) the only anomaly was an absent right lower lobe of the lung noted on computed tomography scan after birth. There was
only 1 case in which no intracardiac or extracardiac anomalies were noted on prenatal or postnatal examination (case 10). Comment Dextroposition of the fetal heart is an uncommon finding on prenatal ultrasonography. It may be caused by a variety of fetal abnormalities. A reported cause is external compression of the fetal heart and mediastinum, shifting the heart toward the right side of the fetus.8 This was shown in our cases of left-sided congenital diaphragmatic hernia in which the fetal stomach and intestines displaced the heart into the right side of the chest. Another cause of compression and mass effect noted in this series was congenital cystic adenomatoid malformation of the lung. Dextroposition can also be due to hypoplasia of the right lung, with a resultant shift of the heart to the right to fill the void in the right hemithorax. This has been re-
984 Borgida et al
ported in association with the scimitar syndrome, which is described by dextroposition of the heart, maldevelopment of the right lung, and anomalous pulmonary venous return that drains into the vena cava.9 Intracardiac anomalies were also common in our cases of dextroposition, indicating a possible developmental link. Comstock et al10 have hypothesized that the right-sided fetal heart may be due to abnormal looping during cardiac development. Although only 2 cases in this study had chromosomal abnormalities (14%), the finding of dextroposition warrants amniocentesis for karyotype. There was only 1 case in which dextroposition was an isolated finding. Other authors have reported on the significance of an abnormal fetal cardiac axis deviation. In a series of 24 fetuses noted to have a right fetal cardiac axis, numerous intracardiac and extracardiac anomalies were noted.10 Similar findings have also been reported with a left fetal cardiac axis.6 This report of our clinical and sonographic findings may be important information for patient counseling because, to our knowledge, no other series of fetal dextroposition has been reported. On the basis of the review of our fetal echocardiogram database, dextroposition of the fetal heart is an unusual finding frequently associated with intracardiac and extracardiac anomalies. When dextroposition is noted, a targeted ultrasound, fetal echocardiogram, and fetal karyotype should be offered.
October 1998 Am J Obstet Gynecol
REFERENCES
1. Ott WJ. The accuracy of antenatal fetal echocardiography screening in high-risk and low-risk populations. Am J Obstet Gynecol 1995;172:1741-7. 2. Sinclair BG, Sandor GG, Farquharson DF. Effectiveness of primary level antenatal screening for severe congenital heart disease: a population based assessment. J Perinatol 1996;16:336-40. 3. Stumpflen I, Stumpflen A, Wimmer M, Bernaschek G. Effect of detailed fetal echocardiography as part of routine prenatal ultrasonographic screening on detection of congenital heart disease. Lancet 1996;348:854-7. 4. Copel JA, Pilu G, Green J, Hobbins JC, Kleinman CS. Fetal echocardiographic screening for congenital heart disease: the importance of the four-chamber view. Am J Obstet Gynecol 1987;157:648-55. 5. Crane JM, Ash K, Fink N, Desjardins C. Abnormal fetal cardiac axis in the detection of intrathoracic anomalies and congenital heart disease. Ultrasound Obstet Gynecol 1997;10:90-3. 6. Smith RS, Comstock CH, Kirk JS, Lee W. Ultrasonographic left cardiac axis deviation: a marker for fetal anomalies. Obstet Gynecol 1995;85:187-91. 7. Shipp TD, Bromley B, Hornberger LK, Nadel A, Benacerraf BR. Levorotation of the fetal cardiac axis: a clue for the presence of congenital heart disease. Obstet Gynecol 1995;85:97-102. 8. Sherer DM, Eglinton GS, Goncalves LF, Lewis KM, Queenan JT. Prenatal and pulsed Doppler sonographic documentation of intrathoracic umbilical vein and ductus venosus, confirming extensive hepatic herniation in left congenital diaphragmatic hernia. Am J Perinatol 1996;13:159-62. 9. Grisaru D, Achiron R, Lipitz S, Yahav J, Hegesh J, Rotstein Z. Antenatal sonographic findings associated with scimitar syndrome. Ultrasound Obstet Gynecol 1996;8:131-3. 10. Comstock CH, Smith R, Lee W, Kirk JS. Right fetal cardiac axis: clinical significance and associated findings. Obstet Gynecol 1998;91:495-9.
Key words: Fetal echocardiogram, congenital heart disease, dextroposition
Fetal echocardiography will diagnose congenital heart disease in the antepartum period in 40% to 85% of cases.1-3 A four-chamber view is an essential part of a fetal ultrasonogram and has been reported to be a useful screening tool for detecting congenital heart disease.4 The axis of the fetal heart in the chest has also been reported to be useful in screening for congenital heart disease.5, 7 When the fetal heart is displaced from the normal position in the chest, intracardiac and extracardiac fetal anomalies may be present. The purpose of this study was to evaluate the associated anomalies in cases of dextroposition of the fetal heart detected at the time of fetal echocardiogram.
Francis Hospital and Medical Center. Both institutions are tertiary level referral centers for prenatal diagnosis. For the purposes of this study, dextroposition of the fetal heart was defined as most of a normally connected fetal heart found on the right side of the fetal chest (Fig 1). True dextrocardia, situs inversus in the thorax, was an exclusion for the study. Intracardiac and extracardiac fetal anomalies were reviewed from patient reports and by reviewing ultrasonograms. All available karyotypes and postnatal examinations were reviewed. Data were analyzed using descriptive statistics. Results
Methods Our fetal echocardiography database was retrospectively searched from January 1990 through December 1996 to identify all cases referred or diagnosed with dextroposition of the fetal heart. The database is maintained by the Divisions of Maternal-Fetal Medicine at the University of Connecticut Health Center and Saint
From the Departments of Obstetrics and Gynecology, University of Connecticut School of Medicine, and Saint Francis Hospital and Medical Center. Presented at the Eighteenth Annual Meeting of the Society of Perinatal Obstetricians, Miami Beach, Florida, February 2-7, 1998. Reprints not available from the authors. Copyright © 1998 by Mosby, Inc. 0002-9378/98 $5.00 + 0 6/6/92572
982
During the study period 2882 fetal echocardiograms were performed with a mean gestational age of 25.3 weeks. Sixty percent of the fetal echocardiograms were performed at the University of Connecticut (1734 of 2882), the remainder were performed at Saint Francis Hospital and Medical Center. Fourteen cases of dextroposition were identified (0.5%); 9 cases were identified at the University of Connecticut and 5 cases at Saint Francis Hospital and Medical Center. The referral indications for all the fetal echocardiograms performed during the study period are shown in Table I. Intracardiac anomalies were noted in 9 of 14 (64%) cases, whereas extracardiac anomalies were noted in 6 of 14 (43%) cases. Fetal karyotype was available in 11 of 14 (79%) cases. An abnormal karyotype was found in 2
Borgida et al 983
Volume 179, Number 4 Am J Obstet Gynecol
Table I. Indications for fetal echocardiogram in study population (N = 2882) Reason
No.
%
Family history of congenital heart disease Diabetes mellitus Dysrhythmia Medication exposure Suspected congenital heart disease Advanced maternal age Fetal anomalies Chromosomal anomalies Other
605
21
432 318 317 260
15 11 11 9
258 202 87 403
9 7 3 14
Fig 1. Four-chamber view of dextroposition of fetal heart.
Table II. Findings in study cases Case No.
Gestational age (wk)
Referral diagnosis
Intracardiac findings
Extracardiac findings
1 2 3 4 5 6 7 8 9 10 11 12 13 14
21.7 19.1 25.7 25.0 34.9 21.7 32.7 30.3 20.6 19.0 20.5 20.4 23.6 20.1
Advanced maternal age Diabetes Fetal anomaly Dysrhythmia Cardiac position Fetal anomaly Fetal anomaly Fetal anomaly Diabetes Cardiac position Cardiac position Advanced maternal age Diabetes Cardiac position
AV canal HPLH VSD AV canal AV canal None None None VSD transposition None None HPLH AV canal VSD
Trisomy 18, hydrocephalus None Hydrocephalus, multiple defects None None CCAML type II Diaphragmatic hernia Diaphragmatic hernia Diaphragmatic hernia None Absent lower lobe right lung Translocation X, 19 None None
AV, Atrioventricular; HPLH, hypoplastic left heart; VSD, ventriculoseptal defect; CCAML, congenital cystic adenomatoid malformation of the lung.
(14%) cases. The cases are summarized in Table II. The most common intracardiac anomaly was an atrioventricular canal defect noted in 29% of cases. Congenital diaphragmatic hernia was the most common extracardiac defect noted in 21% of cases. All the congenital diaphragmatic hernias (cases 7, 8, and 9) were left sided as was the 1 case of congenital cystic adenomatoid malformation of the lung (case 6). There were multiple ultrasonographically detected findings in the 1 case of trisomy 18 (case 1). These included choroid plexus cysts, hypotelorism, micrognathia, hand clenching, and rocker bottom feet. In the other chromosomally abnormal case (case 12) hypoplastic left heart syndrome was the only ultrasonographic finding. Overall, 13 of 14 (86%) cases had major associated congenital anomalies that were confirmed by postnatal examination or autopsy. In one case (case 11) the only anomaly was an absent right lower lobe of the lung noted on computed tomography scan after birth. There was
only 1 case in which no intracardiac or extracardiac anomalies were noted on prenatal or postnatal examination (case 10). Comment Dextroposition of the fetal heart is an uncommon finding on prenatal ultrasonography. It may be caused by a variety of fetal abnormalities. A reported cause is external compression of the fetal heart and mediastinum, shifting the heart toward the right side of the fetus.8 This was shown in our cases of left-sided congenital diaphragmatic hernia in which the fetal stomach and intestines displaced the heart into the right side of the chest. Another cause of compression and mass effect noted in this series was congenital cystic adenomatoid malformation of the lung. Dextroposition can also be due to hypoplasia of the right lung, with a resultant shift of the heart to the right to fill the void in the right hemithorax. This has been re-
984 Borgida et al
ported in association with the scimitar syndrome, which is described by dextroposition of the heart, maldevelopment of the right lung, and anomalous pulmonary venous return that drains into the vena cava.9 Intracardiac anomalies were also common in our cases of dextroposition, indicating a possible developmental link. Comstock et al10 have hypothesized that the right-sided fetal heart may be due to abnormal looping during cardiac development. Although only 2 cases in this study had chromosomal abnormalities (14%), the finding of dextroposition warrants amniocentesis for karyotype. There was only 1 case in which dextroposition was an isolated finding. Other authors have reported on the significance of an abnormal fetal cardiac axis deviation. In a series of 24 fetuses noted to have a right fetal cardiac axis, numerous intracardiac and extracardiac anomalies were noted.10 Similar findings have also been reported with a left fetal cardiac axis.6 This report of our clinical and sonographic findings may be important information for patient counseling because, to our knowledge, no other series of fetal dextroposition has been reported. On the basis of the review of our fetal echocardiogram database, dextroposition of the fetal heart is an unusual finding frequently associated with intracardiac and extracardiac anomalies. When dextroposition is noted, a targeted ultrasound, fetal echocardiogram, and fetal karyotype should be offered.
October 1998 Am J Obstet Gynecol
REFERENCES
1. Ott WJ. The accuracy of antenatal fetal echocardiography screening in high-risk and low-risk populations. Am J Obstet Gynecol 1995;172:1741-7. 2. Sinclair BG, Sandor GG, Farquharson DF. Effectiveness of primary level antenatal screening for severe congenital heart disease: a population based assessment. J Perinatol 1996;16:336-40. 3. Stumpflen I, Stumpflen A, Wimmer M, Bernaschek G. Effect of detailed fetal echocardiography as part of routine prenatal ultrasonographic screening on detection of congenital heart disease. Lancet 1996;348:854-7. 4. Copel JA, Pilu G, Green J, Hobbins JC, Kleinman CS. Fetal echocardiographic screening for congenital heart disease: the importance of the four-chamber view. Am J Obstet Gynecol 1987;157:648-55. 5. Crane JM, Ash K, Fink N, Desjardins C. Abnormal fetal cardiac axis in the detection of intrathoracic anomalies and congenital heart disease. Ultrasound Obstet Gynecol 1997;10:90-3. 6. Smith RS, Comstock CH, Kirk JS, Lee W. Ultrasonographic left cardiac axis deviation: a marker for fetal anomalies. Obstet Gynecol 1995;85:187-91. 7. Shipp TD, Bromley B, Hornberger LK, Nadel A, Benacerraf BR. Levorotation of the fetal cardiac axis: a clue for the presence of congenital heart disease. Obstet Gynecol 1995;85:97-102. 8. Sherer DM, Eglinton GS, Goncalves LF, Lewis KM, Queenan JT. Prenatal and pulsed Doppler sonographic documentation of intrathoracic umbilical vein and ductus venosus, confirming extensive hepatic herniation in left congenital diaphragmatic hernia. Am J Perinatol 1996;13:159-62. 9. Grisaru D, Achiron R, Lipitz S, Yahav J, Hegesh J, Rotstein Z. Antenatal sonographic findings associated with scimitar syndrome. Ultrasound Obstet Gynecol 1996;8:131-3. 10. Comstock CH, Smith R, Lee W, Kirk JS. Right fetal cardiac axis: clinical significance and associated findings. Obstet Gynecol 1998;91:495-9.