What do we know about Heterotaxy Syndrome? - An illustrated guide.

Transcription

1 What do we know about Heterotaxy Syndrome? - An illustrated guide. Poster No.: C-2369 Congress: ECR 2015 Type: Educational Exhibit Authors: M. C. Ageitos Casais, A. X. Martínez de Alegría Alonso, C. Valeiras Crujeiras, A. Arango Díaz, M. V. Trujillo Ariza ; 1 2 Santiago de Compostela/ES, Ribeira/ES Keywords: Anatomy, Cardiovascular system, Abdomen, CT, Education, elearning, Arteriovenous malformations, Congenital DOI: /ecr2015/C-2369 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 26

2 Learning objectives We describe the anatomic disorders that can be seen in the different imaging techniques in the Heterotaxy syndrome. This entity is part of the situs anomalies that can be present in humans, causing different visceral and vascular malpositions classically classified in situs inversus or situs ambiguus depending on the disorganization of the organs. We review the key imaging findings in each entity because they may be misleading due to the great variability. Subtle variations in the anatomic arrangement can be misreaded and not detected causing a misdiagnosis. This is why is so important for the radiologist to understand the different presentations of this spectrum to make the accurate diagnosis. Background Heterotaxy syndrome is a rare anomaly of the anatomic body arrangement that unless its uncommon frequency it is well-known in the pediatric age. In adults this syndrome is rarely diagnosed because this patients usually have severe congenital cardiac anomalies that are a cause of early death. Within the patients that reach the adult age, the cardiac anomalies usually are mild and the diagnosis is an incidental finding. TERMINOLOGY Situs means the position of the heart and abdominal viscera according to the median line. Situs solitus is the cardiac and abdominal normal disposition, with the cardiac apex, spleen, stomach and aorta to the left and liver and inferior vena cava to the right. Situs inversus is a mirror image of the situs solitus, occuring in about 0.01% of the population. It presents with congenital cardiac anomalies in 3-5%, with atrioventricular discordance and transposition of the great vessels being the most frequent alterations. Another frequent association of situs inversus is the respiratory involvement in the Kartagener syndrome occuring in 20%. Situs ambiguus, also known as Heterotaxy syndrome consists in the desorganized and unpredictable arrangement of the organs, without a patognomonic feature. This entitiy is classically classified in polyesplenia and asplenia or in right isomerism and left isomerism. Page 2 of 26

3 Isomerism refers to the situation where the morfologically right or left organs are located in both sides of the body in the same patient. Fig. 12: Spectrum of radiological presentations in the Heterotaxy syndrome References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES In left isomerism both atria have the morphology of the left atrium, usually both with pulmonary veins and lungs bilaterally bilobar with long main bronchi. This type presents with polyesplenia and inferior vena cava interruption and clinically is unsuspected because it has inespecific symptoms and low mortality. In right isomerism both atria are morphologically right, lungs are bilaterally trilobar with short main bronchi and absence of spleen. Most of the patients have pulmonary outflow obstruction and 40% pulmonary atresia. This isomerism is frequently diagnosed during the early years due to occur with cyanotic cardiac disease or severe respiratory distress associated with immunologic complications due to the asplenia reaching a mortality of 85% in the first year. Page 3 of 26

4 Fig. 1: Draw of both types of isomerism in Heterotaxy syndrome. References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES A recent study estimated that asian population have a higher prevalence (about 32%) than occidental population. SPLEEN: Heterotaxy syndrome with Asplenia: In this group a congenital absence of the spleen is found, causing a severe immunologic disorder. Heterotaxy syndrome with Polyesplenia: Multiple small spleens or more rarely, a lobulated spleen are found usually located proximal to the stomach (frequently along the greater curvature) due to its dorsal mesogastric embryologic origin. They can be in the left or right hypochondrium. Page 4 of 26

5 Fig. 2: Patient with right-sided polyesplenia (arrows). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES LUNGS AND BRONCHI: Heterotaxy syndrome with Asplenia: It is known a strong association with the presence of right isomerism: both lungs are trilobar with bilateral minor fissures and eparterial bronchi, meaning that both main bronchi are short and located superiorly to the pulmonary artery branches. Heterotaxy with Polyesplenia: Usually associated with left isomerism: bilobar lungs with hyparterial bronchi (long bronchi running inferiorly to the pulmonary artery branches). Page 5 of 26

6 Fig. 4: Bilaterally trilobated lungs showing minor fissures but with main bronchi in the normal arrangement (right eparterial bronchus and left hyparterial bronchus). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES Page 6 of 26

7 Fig. 3: There is minor fissures in both lungs (yellow arrows), being trilobated (right isomerism). There is also basal bronchiectasis (red arrow). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES Page 7 of 26

8 Fig. 9: Left isomerism: Absence of minor fissure in the right lung (both lungs are bilobated). Also, both main bronchi are long and hyparterial (red arrows) References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES HEART: Page 8 of 26

9 Heterotaxy with asplenia: Patients with asplenia usually have severe cardiac malformations associated, so only few of them reach the adult age. The most common malformations are common atrioventricular channel, univentricular heart and transposition of great vessels. All of them present with anomaly of the pulmonary drainage. Heterotaxy with Polyesplenia: In this group cardiac malformations are milder and less common. Fig. 6: Patient with dextrocardia and right sided aortic arch. Both atria are elongated and narrow (yellow arrows in b), a finding of left isomerism. Pulmonary veins can be seen originated from the right atrium (figures c and d), with a dense material in the left pulmonary vein ostium (long arrow) from prior surgery. A morphologically left ventricle Page 9 of 26

10 is in the right side of the heart (red asterisk) while the morphologically right is in the left side (yellow asterisk). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES IVC, AZYGOS AND AORTA: In Heterotaxy with polyesplenia the most frequent anomaly is the interruption of the inferior vena cava with continuation through the azygos vein or the hemiazygos associated with a short intrahepatic course of the IVC. In plain radiography, this can be seen as an absence of the normal IVC silhouette in the lateral projection in the posteroinferior border of the heart. Also, a prominent azygos vein in the PA projection is found. Fig. 5: Patient with dextrocardia and interruption of IVC with Azygos vein continuation. The PA projection shows a prominent Azygos (blue arrows) and the lateral projection shows the absence of the IVC silhouette (yellow arrowhead). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES LIVER: In both Asplenia and Polyesplenia groups, the presence of a bridge liver is a common feature but is more common in the Asplenia type. Page 10 of 26

11 Fig. 7: Variability of the liver arrangement. In figures a and b the liver has a bridge configuration with left polyesplenia. In figure c there is also a bridge liver but with right polyesplenia. In figure d the liver is left sided. References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES PANCREAS: In most of the cases described in the existent literature, pancreas is truncated or incomplete. Page 11 of 26

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13 Fig. 10: Figure a: Truncated pancreas but only the head is present (yellow arrow). Figure b: Truncated pancreas with head and also a small portion of the pancreatic body present (red arrow). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES GASTROINTESTINAL TRACT: Intestinal malrotation is a common feature in both asplenia and polyesplenia types of Heterotaxy syndrome. Fig. 8: Patient with right sided polyesplenia with the stomach in the right side and intestinal malrotation: all the colon is located in the left hemiabdomen (blue arrows) while the small intestine is in the right hemiabdomen (red arrows). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES Page 13 of 26

14 Fig. 11: Polyesplenia with intestinal malrotation: the colon is completely right sided (blue arrows) and the small intestine is on the left side (red arrows). References: Complexo Hospitalario Universitario de Santiago de Compostela (CHUS) - Santiago de Compostela/ES Images for this section: Page 14 of 26

15 Fig. 1: Draw of both types of isomerism in Heterotaxy syndrome. Fig. 2: Patient with right-sided polyesplenia (arrows). Page 15 of 26

16 Fig. 3: There is minor fissures in both lungs (yellow arrows), being trilobated (right isomerism). There is also basal bronchiectasis (red arrow). Page 16 of 26

17 Fig. 4: Bilaterally trilobated lungs showing minor fissures but with main bronchi in the normal arrangement (right eparterial bronchus and left hyparterial bronchus). Page 17 of 26

18 Fig. 5: Patient with dextrocardia and interruption of IVC with Azygos vein continuation. The PA projection shows a prominent Azygos (blue arrows) and the lateral projection shows the absence of the IVC silhouette (yellow arrowhead). Page 18 of 26

19 Fig. 6: Patient with dextrocardia and right sided aortic arch. Both atria are elongated and narrow (yellow arrows in b), a finding of left isomerism. Pulmonary veins can be seen originated from the right atrium (figures c and d), with a dense material in the left pulmonary vein ostium (long arrow) from prior surgery. A morphologically left ventricle is in the right side of the heart (red asterisk) while the morphologically right is in the left side (yellow asterisk). Fig. 7: Variability of the liver arrangement. In figures a and b the liver has a bridge configuration with left polyesplenia. In figure c there is also a bridge liver but with right polyesplenia. In figure d the liver is left sided. Page 19 of 26

20 Fig. 8: Patient with right sided polyesplenia with the stomach in the right side and intestinal malrotation: all the colon is located in the left hemiabdomen (blue arrows) while the small intestine is in the right hemiabdomen (red arrows). Page 20 of 26

21 Fig. 9: Left isomerism: Absence of minor fissure in the right lung (both lungs are bilobated). Also, both main bronchi are long and hyparterial (red arrows) Page 21 of 26

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23 Fig. 10: Figure a: Truncated pancreas but only the head is present (yellow arrow). Figure b: Truncated pancreas with head and also a small portion of the pancreatic body present (red arrow). Fig. 11: Polyesplenia with intestinal malrotation: the colon is completely right sided (blue arrows) and the small intestine is on the left side (red arrows). Fig. 12: Spectrum of radiological presentations in the Heterotaxy syndrome Page 23 of 26

24 Findings and procedure details We reviewed the diagnosed situs anomalies in the last 5 years at our institution, finding 5 cases with Heterotaxy syndrome. FINDINGS: SPLEEN: All of our 5 patients presented with polyesplenia with multiple spleens located adjacent to the stomach, being 3 in the right side of the body and 2 in the left. LUNGS AND BRONCHI: One of them showed trilobar lungs with minor fissures but with an eparterial right bronchus and a hyparterial left bronchus, corresponding with the normal bronchi arrangement. In another patient we found left isomerism, with both lungs bilobated and hyparterial bronchi. Another case showed trilobulated lungs (that may correspond to right isomerism) but both bronchi had a long course (that may indicate left isomerism). In this patient basal bronchiectasis are also found that may indicate a Kartagener syndrome. In the fourth patient we found both lungs and bronchi with the normal distribution. In the fifht patient we cannot accurately precise the pulmonary anatomy due to the lack of thoracic imaging scan. HEART: In our serie 2 patients showed dextrocardia, 4 a normal atrioventricular morphology and one had left isomerism with both atria morphologically left with pulmonary veins at birth. IVC, AZYGOS AND AORTA: All our patients have IVC interruption with continuation through the Azygos vein with 3 of them having a infrahepatic right IVC and 2 left IVC. In 4 patients the IVC continuates with an ipsilateral Azygos vein but one had a contralateral Azygos vein. Page 24 of 26

25 Aortic arch is located to the right in 2 patients and to the left in the other 3. LIVER: 2 of our patients had a bridge liver, 2 with a left located liver and the last one with a right located liver. PANCREAS: All our cases had truncated pancreas. GASTROINTESTINAL TRACT: 3 of our patients had intestinal malrotation, with 2 of them with de small intestine arranged to the left and all the colon in the right side. The other malrotation case had the inverse disposition. One of our patients have a mirror-distribution of the gastrointestinal tract. Conclusion After reviewing our serie and the existent medical literature, we can conclude without doubts that there is no patognomonic common feature. However, the common features in our group of Heterotaxy with Polyesplenia patients is the interruption of the inferior vena cava with continuation through the Azygos vein and the truncated pancreas. This variability is the reason why the radiological report must not only stablish the Heterotaxy syndrome with or without polyesplenia, but to detailed describe de disposition of each organ, avoiding future complications. Personal information References 1. Applegate KE, Goske MJ, Pierce G, Murphy D. Situs revisited: imaging of the heterotaxy syndrome. RadioGraphics 1999; 19: Page 25 of 26

26 2. Kim SJ, Kim WH, Lim HG, Lee JY. Outcome of 200 patients after an extracardiac Fontan procedure. J Thorac Cardiovasc Surg 2008; 136: Ann S. Fulcher, MD # Mary Ann Turner, MD. Abdominal manifestations of Anomalies in Adults. Radiographics 2002; 22: : Van Mierop LHS, Gessner IH, Schiebler GL. Asplenia and polysplenia syndromes. Birth Def 1972; 8: Jacobs JP, Anderson RH, Weinberg PM, et al. The nomenclature, definition and classification of cardiac structures in the setting of heterotaxy. Cardiol Young 2007;17(Suppl 2):S Calder A.L. Thoracic Situs As an Indicator of Atrial Appendage Morphology: A Postmortem Study of 306 Specimens With Situs Solitus in 250 and Heterotaxy in 56 Cases. Pediatr Cardiol (2011) 32: Lehner S., Kozlik-Feldmann R., Herrmann F., Dalla-Pozza R., Netz H., Malec E., JAnuszewska K. An Unusual Form of Supracardiac Total Anomalous Pulmonary Venous Return Via a Right-Sided Vertical Vein in a Heterotaxy Syndrome Case. Pediatric Cardiology 2012, Feb Kobayashi D., Edwards H., Singh J., Nadkarni M., Lantz P., Cook A. Portopulmonary Hypertension Secondary to Congenital Extrahepatic Portosystemic Shunt With Heterotaxy and Polysplenia: A Cause of Sudden Death in an Infant. Pediatr Pulmonol. 2011;46: Imamura T., Momoi N., Go H., Ogasawara K., Sato M., Hosoya M. Rare case of isolated levocardia with polysplenia including normally structured lung without cardiac anomaly. Congenital Anomalies 2011; 51, Page 26 of 26