1. Case Study A. Swartbooi Diagnostic Radiology, UFS 9 March 2012

2. Patient Info 46 yr old male pt Known cardiac pt Previous Mitral valve replacement Complaint of dyspnoea and orthopnoea

3. Clinical Presentation Chronically ill (RVD on Rx) Pulse & Temp N BP 110/80 Blood results N

4. Imaging CXR

5. Findings: –Dextrocardia –Cardiomegaly –Post Sternotomy wires –Right gastric air bubble –Left sided liver –Left lower pleural disease

6. Imaging Heart Sonar Findings –Dextrocardia –Global hypokinesia –EF 32%

7. Diagnosis Dextrocardia with situs inversus

8. Investigations Further evaluation in pt with abovementioned chest findings include: –Abdominal ultrasound If inconclusive –CT abdomen –MRI –Angiography

9. Imaging Critical structures for evaluation of situs –Cardiac apex –Atria –Lungs (bi- or trilobed) –Subdiaphragmatic venous Drainage –Aorta relative to midline –Stomach position (? malrotation) –Liver and gallbladder –Spleen (presence, appearance, number)

10. Imaging modalities Chest x-ray –Plain chest and abdominal x-rays are the first imaging modalities –Presence or absence of normal situs Evaluate heart Stomach air bubble Liver outline

11. Imaging modalities Ultrasound –Evaluate intra-abdominal solid organs Spleen Liver –Vasculature Relation of large vessels

12. Imaging modalities Transthoracic echocardiography –Directly visualize cardiovascular anomalies CT MRI Angiocardiography (Less commonly used)

13. Introduction Situs anomalies are often confusing, in part because of the overlapping features of some anomalies NB to understand the terminology Situs refers to the position of the heart and viscera relative to midline.

14. Terminology Situs Solitis Situs inversus Situs ambiguous/Heterotaxy

15. Situs Solitus Situs solitus –Represents the normal position of the heart and abdominal viscera, with the cardiac apex, spleen, stomach, and aorta located on the left and the liver and inferior vena cava (IVC) located on the right –Congenital heart disease occurs in less than 1% of individuals with situs solitus –In case of dextrocardia 95% chance of CHD

16. Situs Solitus

17. Situs Inversus –Indicates mirror-image location of the organs compared to situs solitus –NB to recognize May help avoid mishaps at surgery or other interventions, particularly in the emergency setting –Two major subcategories Situs inversus with dextrocardia Situs inversus with levocardia

18. Situs Inversus

19. Situs inversus with dextrocardia –Situs inversus totalis –More common –Heart and viscera relative to situs solitus –Cardiac apex, spleen, stomach, and aorta located on the right and the liver and IVC located on the left –3-5 % chance of CHD

20. Situs Inversus

21. Situs inversus with levocardia –Extremely rare –Mirror-image location of the viscera relative to situs solitus and a left-sided cardiac apex –95 % chance of CHD

22. Heterotaxy Heterotaxy syndrome –Rare condition that occurs in approximately 0.8% of patients with congenital heart disease –Abnormal arrangement of organs and vessels as opposed to the orderly arrangement typical of situs solitus and situs inversus

23. Heterotaxy Patients with heterotaxy syndrome have a high probability of having severe complex cardiovascular anomalies (50 – 100%) Characterized not by a single set of abnormalities but by a spectrum of abnormalities Encompasses 2 groups of diseases Asplenia Polysplenia

24. Heterotaxy Situs ambiguous with asplenia aKa Right isomerism or bilateral right-sidedness Findings include –Bilat Trilobed lungs (minor fissures bilat) –Eparterial bronchi –Bilat left atria –Central liver –Stomach position indeterminate –Absent spleen –IVC and Aorta on same side of vertebra **

25. Heterotaxy

26. Situs ambiguous with asplenia –99%–100% prevalence of congenital heart disease –Common cardiac anomalies Common atrioventricular canal Univentricular heart TGA TAPVR –More in males –Death in 1 st yr of life up to 80% –Asplenia related to greater risk for sepsis Carefull search for spleen NB

27. Heterotaxy Asplenia

28. Heterotaxy Situs ambiguous with polysplenia aKa Left isomerism or bilateral left-sidedness Findings include –Bilat bilobed lungs –Bilat pulm atria –Central liver –Stomach position indeterminate –Multiple spleens –IVC interuption with continuation of azygos system No single anomaly is pathognomonic

29. Heterotaxy

30. Situs ambiguous with polysplenia –Cardiac anomalies less common and less complex (50-90%) –Most common cardiac anomalies PAPVR ASD Atrioventricular canal –More in females

31. Heterotaxy Polysplenia

32. Summary

33. Situs anomalies are often detected incidentally, with ⇧ frequency, in adults during imaging evaluation for unrelated conditions It is important for radiologists to become familiar with these anomalies, the spectrum of their manifestations, and their significance Not all patients with heterotaxy present with the classic features of either asplenia or polysplenia

34. Summary Nb to utilize an individualized approach in these patients reflecting the unique anatomy –eg. Heterotaxy syndrome (bilateral bilobed lungs, levocardia, left sided malrotated stomach) A complete, correct anatomic diagnosis cannot only lead to earlier intervention, but also provide some indication of prognosis

35. THANK YOU

36. References RadioGraphics 2002; 22:1439–1456 RadioGraphics 1999; 19:837-852 American Journal of Cardiology Volume 81, Issue 2, Pages 188-194, 15 January 1998 Dahnert. Radiology Review Manual, page 593-594 Weisleder. Primer of Diagnostic Radiology, page 139-140