1. Cardiac Malpositions
Dr Sreejith A G

2. 1606 -The malposition was mentioned by Hieronymus
1858 -Thomas Peacock2 : “The heart may be congenitally misplaced in various ways, occupying either an unusual position within the thorax, or being situated external to that cavity.”
1915- Maude Abbott described ectopia cordis.
In Maria de la Cruz-embryologic basis of the malpositions
1966 -Elliott et al’s radiologic classification
1977 -landmark observations Van Praagh
Dextrocardia was 1 of the first congenital malformations
of the heart to be recognizedEstimated prevalence is
0.10 per 1,000 live births.

3. Terminology
Cardiac malposition : An abnormal intra-thoracic position of the heart.
Situs : Site or position of the viscera or atria.
Solitus : Normal or usual.
Situs solitus : Normal position
Depends on abdominal Situs and position of heart in the thorax . two logical Situs these are Situs Solitus (Normal) and its opposite Situs Inversus

4. Situs inversus: Mirror image / inversion or right/left reversal
of visceral or atrial site or position
Situs ambiguous : because of symmetric
or indeterminate anatomy bilaterally
uncertain or
indeterminate visceral or atrial
position

5. Terminology The intrathoracic Cardiac position
( levocardia / dextrocardia / mesocardia)
Dextrocardia : the location of the heart in the right hemithorax with the base to apex axis to the right

6. Mesocardia :
cardiac base to apex axis directed to the midline
ventricular apices equally directed to both right and left sides
Levocardia :
apex (base to apex axis) pointing to the left.
malposition with situs inversus and situs ambiguus .

7. Situs Solitus

9. abdominal Situs and position of heart in the thorax
abdominal Situs and position of heart in the thorax. There are two logical Situs these are Situs Solitus (Normal) and its opposite Situs Inversus. So they are two logical cardiac positions Levocardia and Dextrocardia.

11. Terminology
Displacement (dextroposition) : secondary to eventration of a hemidiaphragm, agenesis of a lung, or congenital complete absence of the pericardium

12. Terminology
Ectopia cordis : Location of the heart outside the thoracic cavity

13. Terminology
Great arterial designations: The ascending aorta and pulmonary trunk defined by their ventricle of origin and by their morphology
Heterotaxy : Greek “heteros” : different and “taxis” : arrangement
Isomerism : Greek “isos” : equal and “meros” part.
The similarity of bilateral structures that are normally dissimilar
Chamber designations: Right and left, as in right and left atrium and right and left ventricle.

14. Juxtaposition of the atrial appendages (JAA)
malposition of one of the two atrial appendages.
In situs solitus, juxtaposition of the morphologically right atrial appendage places both atrial appendages on the left side of the great arteries
Importance-balloon atrial septostomy
Diagnosis of JAA prior to the procedure
is important as positioning the balloon in the atrial
appendage can cause rupture during balloon inflation and pullback
with potential catastrophic consequences

15. Concordance Latin “concordare” : to agree.
Atrioventricular concordance:
Connection of a morphologic atrium to a corresponding morphologic ventricle.
Ventriculoarterial concordance:
Connection of a morphologic right ventricle to a pulmonary trunk and a morphologic left ventricle to an aorta.
A loop that agrees with the visceroatrial situs

16. Discordance Latin “dis” : apart / Inappropriate.
Atrio-ventricular discordance:
A morphologic RA to LV LA to RV.
Ventriculo-arterial discordance:
A morphologic RV gives rise to the aorta, and LV to the pulmonary trunk
Double discordance:
Atrio-ventricular discordance together with ventriculo-arterial discordance.
The result is physiologically correct circulatory flow.

17. Isolated ventricular inversion
Transposition:
Each great artery arises from an anatomically discordant ventricle
malposition of the great arteries:
Abnormal spatial relations of great arteries
arises from the anatomically correct ventricle.
Isolated ventricular inversion
not associated with transposition of the great arteries
Inversion : Mirror imagery

18. Looping of heart D-loop: Rightward (“dextro”) bend.
L-loop: Leftward (“levo”) bend
late fourth week and early fifth week
The straight heart tube of the embryo forms the left ventricle of the definitive heart. Looping is the consequence of the addition of new material at the arterial pole of the developing heart

19. Looping
 heart tubes forms constrictions defining separate components of the heart (cranial to caudal): Bulbus cordis, ventricle and atrium.
The bulbus cordis is continuous with the truncus arteriosus which connects cranially to the aortic sac.
The primitive atrium is still paired and connects caudally to the paired sinus venosus. Both the atrium and sinus venosus are outside the pericardial sac

20. The straight heart tube elongates with simultaneous growth in the bulbus cordis and primitive ventricle.
bend ventrally and rotate to the right, forming a C-shaped loop with convex side situated on the right.

21. The ventricular bend moves caudally
atrium and sinus venosus become dorsal to the heart loop
The embryonic straight heart tube initially bends to the right (d-loop), then moves to the left until the ventricular portion occupies a normal left thoracic positionThe atrial and outflow poles converge and myocardial cells are added, forming the truncus arteriosus

23. does not address other lesions discussed in chapters dealing with double-inlet ventricles, double-outlet ventricles, or single-outlet hearts

24. Situs solitus with Dextrocardia
Isolated dextrocardia with AV concordance and NRGA
The base-to-apex axis points to the right
the right hemidiaphragm is lower than the left
The embryonic straight heart tube initially bends rightward (d-loop) but fails to move into the left chest.
the lungs and abdominal viscera are normally positioned
the ascending aorta and aortic knuckle are normally located
the descending aorta runs its normal course along the left side of the vertebral column,

25. Congenital heart defects:
ventricular septal defect
left SVC to the coronary sinus
coarctation of the aorta
secundum atrial septal defect
anomalous pulmonary venous connections
complete AV septal defect
Clinical presentation depends on associated lesions

26. Radiographic findings
ECG
atrial activation is normal - P-wave nl
QRS - right-axis deviation
progressive reduction in R-wave voltage
Q waves at standard left precordial sites.
Radiographic findings
heart positioned in the right chest.
Bronchial branching patterns are normal.
left-sided stomach bubble and right-sided liver.

27. Corrected Transposition of the Great Arteries
Isolated Dextrocardia with AV and VA Discordance and Left Anterior Aorta
most common form of dextrocardia
High incidence of associated cardiac anomalies
VSD and PS
Pulmonary atresia,
complete AV septal defect,
mitral atresia (right AV valve),
tricuspid regurgitation (left AV valve) with Ebstein anomal “like malformation, .

28. X-RAY & ECG findings are similar to those observed in dextrocardia with NRGA
CLUE TO TGA :
Absence of septal q, Q in III,aVF, rt precordium
abnormal septal depolarization associated with AV discordance.

29. Situs inversus with Dextrocardia
incidence 1 in 8,000
The thoracic and abdominal viscera are mirror images of normal
usually occurs with a structurally normal heart
SIGNIFICANCE :
The pain of angina pectoris is in the right anterior chest and radiates to the right shoulder and right arm.
The pain of appendicitis is in the left lower quadrant.
Biliary colic is assigned to the left upper quadrant.

30. Situs inversus with Dextrocardia
CHD :
VSD
TOF
pulmonary atresia
complete AV septal defect
OS ASD.
X-ray : visceral situs inversus and dextrocardia.
2. the atria, ventricles, and great arteries are all inverted from their normal location and spatial relationships
Common form of dextrocardia in normal hearts and situs inversus totalis

31. Isolated Levocardia Normal position and base to apex cardiac axis
implies that either situs inversus or situs ambiguus is present.
The lungs and abdominal viscera are mirror images of normal.
Associated with complex
congenital heart disease

32. Mesocardia
longitudinal axis of the heart lies in the mid sagittal plane, with the heart possessing no distinct apex.
very low incidence
Mostly with situs solitus
consisted of
normal hearts
corrected TGA
complete transposition of the great arteries

33. Physical examination Apex beat Percussion : Cardiac borders
Right sided liver
Left-sided stomach
In situs solitus with a right thoracic heart, the apical right ventricle retracts, and the systemic morphologic left ventricle generates an outward systolic impulse adjacent to the lower right sternal border

34. Auscultation signs should be compared along the left and right
Splitting of the second sound is prominent on same side of cardiac situs
right sternal borders and at the cardiac apices,
alternating from side to side to compare analogous right and left thoracic sites.

35. ECG
P wave :
The direction of the P wave is determined by atrial situs unless the atrial pacemaker is ectopic
In situs solitus, atrial depolarization from a right sinus node results in normal P-wave axis.
In situs inversus, atrial depolarization is initiated by a left sinus node, P waves are inverted in leads 1 and aVL and upright in lead aVR.
More distinctive but less common is a

36. ECG Right axis deviation
Positive QRS complexes (with upright P and T waves) in aVR
Lead I: inversion of all complexes, ‘global negativity’ (inverted P wave, negative QRS, inverted T wave)
Absent R-wave progression in the chest leads (dominant S waves throughout)
Low voltage in leads V3-V6

37. ECG situs solitus with dextrocardia :
Q waves in leads 1 and aVL.
prominent R waves in leads V1and V2
prominent RS complexes in most of the remaining right precordial leads.
For “correcting” : limb leads unchanged, chest leads recorded from right precordial sites.
Correcting : because atrial situs is normal and the base-to-apex axis points to the right

38. Chest x-ray The first identify the orienting letters L and R.
Situs dermination
Establish the cardiac axis
The relative levels of the 2 hemidiaphragms
Identify concordant bronchial morphology
The ascending aorta is convex at the left basal aspect of the heart
From the radiologic point of view, that is all that is needed to recognize complete situs inversus
Situs inversus with a right thoracic heart is missed if the film is inadvertently reversed when read, because the x-ray then appears “correct.”
LEVEL of hemidiaphragms determined by the location of the cardiac apex, not by the location of the liver.
the descending thoracic aorta runs a course parallel to the left border of the vertebral column

39. echo
apical 4-chamber view: probe is placed on the right chest with the pointer to the left.
For the parasternal long-axis view : right chest with the pointer to the left shoulder.
right parasternal short-axis view: the probe is rotated clockwise from the parasternal long axis, pointing to the left hip

40. Echocardiography Sequential segmental analysis
5 major cardiovascular segments
(visceral,venous,atrial,ventricular , great arteries)
Connections between major segments
(venoatrial,atrio ventricular,ventricular-great arterial)

41. Standard subcostal view 

42. Cardiac position
1 location : most of the cardiac mass left / right / midline
Levoposition or dextroposition or mesoposition
2. cardiac base to apex axis in subcostal four-chamber view

43. Visceral situs
Images of liver,hepatic veins,IVC, stomach, spleen, abd aorta
Spleen-
posterolateral to the stomach
denser appearance than liver
coma shaped curvilinear splenic vein

44.  Situs inversus with dextrocardia is identified by the left atrium to the right of the aorta, the right atrium to the left of the aorta, the aorta to the right of the spinal column
In isomerism, the great vessels lie to the same side of the spine. In left isomerism, the inferior vena cava lies posterior to aorta and is interrupted and continued via a hemi-azygos vein in majority of cases. In right isomerism, the IVC is anterior to the aorta.

45. the hepatic veins will connect directly to the atrium
The visceral situs is considered ambiguous because it does not conform to the classical patterns
Polysplenia : interruption of suprahepatic portion the IVC with azygous continuation,
the hepatic veins will connect directly to the atrium
midline location of abdominal aorta
Atrial and visceral situs inversus. Subcostal short-axis scan of the abdomen provides right-to-left spatial orientation

46. Atrial situs Atrial and visceral situs -usually concordant
Systemic and pulmonary venous connections
  1. Caval position and connection   2. Hepatic veins   3. Coronary sinus   4.Pulmonary venous connection
Pulmonary venous connections often define the left atrium
suprahepatic inferior vena cava defines the right atrium
venous connections and visceral situs may not necessarily agree with the apparent atrial situs in situs ambiguous
The pancreas and spleen are generally located on the same side of the vertebral column as the stomach

47. Atrial Morphology Left Atrium Right Atrium
Triangular, broad based, anterior appendage .
Receives IVC, SVC & coronary sinus.
Septum secundum (limbus of fossa ovale) lies on RA side.
Crista Terminalis is in RA.
Extensive pectinate muscles
Left Atrium
Narrow, fingerlike posterior appendage .
LA receives all 4 pulmonary veins
Septum primum lies on LA side .
LA is smooth with fewer trabeculations
The right & left atria are identified morphologically by their respective atrial appendages and veins emptying into them.

48. Atrial Morphology

49. Pulmonary veins to LA

51. Atrial Situs Atrial Situs Solitus (S) Atrial Situs Inversus (I)
Atrial Situs Ambiguous (A)
Right isomerism (bilateral right atria) or
Left isomerism (bilateral left atria).

52. Identification of the ventricles
AV valve morphology directly correlates with ventricular type
Mitral valve ⇒ LV
No septal chordal attachments
Basal septal annular attachments
2 leaflet
2 large papillary muscles
Elliptical orifice.
Tricuspid Valve ⇒ RV
Septal chordal attachments
Apical septal annular attachment
3 leaflet
Multiple small papillary muscles
Triangular orifice

53. RV Morphology Large apical trabaculations Coarse septal surface
Moderator bands
Cresentic in cross section
Tricuspid – pulmonary discontinuity by crista supraventricularis

54. LV Morphology Small apical trabeculations Smooth upper surface
No moderator band
Mitral – Aortic continuity

56. VENTRICULAR TOPOLOGY
Right hand
Left hand

57. Atrio-ventricular Connections
Concordant ( Normal : RA to RV & LA to LV)
Discordant ( RA to LV & LA to RV)
Univentricular AV connections
Absent AV connection
Common AV valve
Double inlet connections

58. Univentricular AV connections

59. Overriding & Straddling
Biventricular emptying of AV Valve or biventricular origin of a semilunar valve.
Straddling :
Chordae or papillary muscle of the valve attach to contralateral ventricle.
Involve AV Valves and requires presence of VSD.

60. Arterial Morphology
Aorta : artery that gives rise to the coronary arteries and the brachiocephalic vessels.
Pulmonary artery : branches into two but does not give rise to any vessels.

61. Ventriculo-Arterial Connection
Concordant :
Aorta connected to LV and pulmonary artery to RV .
Discordant :
Aorta connected to RV and pulmonary artery to LV .
Double Outlet : Both great arteries arise from a single ventricle.
If more than 50% of an artery overrides a ventricle it is said to be committed to it.

62. Possible Great vessel relations

63. Relation b/w semilunar Valves
Solitus : Aorta posterior and to right.
Inversus : mirror image : Aorta posterior and to left
D-malposition : aortic valve anterior and to the right.
L-malposition : aortic valve anterior and to the left.
Anterior malposition : aortic valve anterior in the middle.
Parasternal and high parasternal short axis and subcostal short axis views are used to recognize the positions of AV and PV.

64. Segmental Expression 1 . Visceroatrial situs : S , I or A.
2 . Ventricular situs : D or L
3 . Position of great vessels : S , I , D , L or A
Normal : S , D , S
Situs inversus Dextrocardia : I , L , I
D TGA : S , D , D
L TGA with situs solitus : S , L , L

65. spatial orientation
the position and orientation of the ventricular septum
levocardia, the ventricles are right anterior and left posterior.
in dextrocardia they usually are right posterior and left anterior
Mesocardia is characterized by a vertical midline septum

66. Pulmonary situs
defined by the relationship of the pulmonary arteries to their adjacent bronchi
morphologic right lung- the pulmonary artery travels anterior to the upper lobe and intermediate bronchi.
morphologic left lung -pulmonary artery courses over the main bronchus and posterior to the upper lobe bronchus
the distance from the carina to the origin of the upper lobe bronchus is 1.5 to 2 times greater for the morphologic left lung

67. Situs Ambiguus
right atrial (asplenia) or left atrial (polysplenia) isomerism
Dextrocardia with situs ambiguus was the most common

68. Criteria for visceral heterotaxy and abnormal visceral symmetry
1 Thoraco-abdominal situs inconsistency
2 Abnormally symmetric lung lobes
3 Abnormally symmetric bronchial branching pattern
4 Abnormal symmetry of the liver
5 Unusual or abnormal systemic venous connections
6 Unroofed coronary sinus
7 Abnormal pulmonary venous connections or drainage
8 Similarities in the shape and morphology of the atrial appendages
9 Abnormal mesenteric attachments
10 Abnormal bowel location +/– malrotation
11 Asplenia, polysplenia or single right-sided spleen
12 Abnormal position and/or size of the pancreas

69. Heterotaxy with right isomerism
a morphologic right bronchus, a trilobed right lung, and a morphologic right atrial appendage
Arrest in cardiac development during the fifth week of gestation
resemblance to the heart of a normal embryo at 35 days of gestation.
growth of the endocardial cushions, septation of the conotruncus, lobation of the lungs and rotation of the gut begin between days 28 and 35 of gestation

70. Situs ambiguus with asplenia
Cardiac :
The sinus nodes are paired
bilateral superior vena cavae are attached to bilateral morphologic right atria.
The P-wave axis is normal
The AVconduction system is equipped with 2 nodes connected by a sling of tissue
Supraventricular tachycardia is attributed to reentry between paired atrioventricular nodes.
serious recurrent infections because of the many immunologic functions of the spleen.
Asplenia is accompanied by

71. Asso.with congenital heart disease
common atrium,
common atrioventricular valve,
morphologicsingle ventricle,
pulmonary stenosis or atresia,
total anomalous pulmonary venous connection
Ventricular and great arterial connections are usually discordant.

72. Noncardiac midline abnormalities
tracheoesophageal fistula, meningomyelocele, encephalocele, cerebellar agenesis, cleft lip, cleft palate, and horseshoe kidney.
Abdomen :
5% of cases, spleen resides in the right upper quadrant.
Howell-Jolly bodies and Pitted red cells in peripheral blood smears
A wandering spleen
Gastrointestinal disorders :biliary atresia and intestinal malrotation, transverse liver
Lungs : bilateral morphologic right bronchi, bilateral trilobed lungs
The spleen is the only organ that is left-sided from its inception, because it develops in the left side of the dorsal mesogastrium.

73. Asplenia / Ivemark syndrome
normal birth weight
male predominance
Neonatal cyanosis is conspicuous, and often evident in the first 24 hours
Survival is determined largely by coexisting congenital heart disease and noncardiac disorders
Most deaths occur within the first few months

74. X-ray : discloses a transverse liver, bilaterally symmetric bronchi
overpenetrated chest x-ray to determine the bronchi
Echocardiography- identifies morphologic right and left atrial appendages
Abdominal USG -a transverse liver, an aorta that is anterior to or on the same side of the spine as the inferior vena cava. A spleen cannot be detected.

75. Heterotaxy with left isomerism:
more prevalent in women
bilateral morphologic left lungs
bilateral morphologic left atrial appendages, bilateral superior vena cavae attached to left atria
an absent or atretic sinoatrial node, common atrium, common atrioventricular valve, atrioventricular septal defect, and partial anomalous pulmonary venous connection.
but it is questionable whether this should be considered partial anomalous drainage

76. polysplenia syndrome
inferior vena caval interruption with azygous continuation,
suprarenal segment of the inferior cava is absent, and the infrarenal segment continues as the azygos or hemiazygous vein
Fetal complete heart block
Intrauterine loss for fetuses
Polysplenia- characterized by a cluster of multiple splenules

77. noncardiac anomalies-gastrointestinal(malrotation, biliary atresia, esophageal atresia and congenital short pancreas)
20% die as neonates; 50% survive adolescence
sinus node is absent or hypoplastic.
The atrial pacemaker is ectopic
Atrial fibrillation and atrial flutter seen
Complete atrioventricular block occurs in approx. 1 in 5 cases
blocked at the level of the penetrating bundle, resulting in nodoventricular discontinuity and a narrow QRS interval

78. Cxr &Usg transverse liver is accompanied by symmetric left bronchi,
The stomach tends to be on the side opposite the descending aorta.
The aorta and inferior vena cava lie anterior to or on the same side of the spine.
hepatic veins connect directly to the atrium without joining the inferior cava

79. Treatment depend on the specific lesion encountered
conotruncal abnormalities (TGA/DORV), surgical correction
two-ventricular-type repair such as an arterial switch procedure

80. complex malformations associated with situs ambiguous
surgical palliation -function as a single ventricle
special efforts toward surgical establishment of appropriate venous connections or relief of venous stenosis
Medical management of complications - progressive hypoxia and polycythemia, progressive ventricular fibrosis, and ventricular failure, stroke, and brain abscess

81. MCQ

82. Interrupted IVC is seen in
Situs inversus
Situs solitus
Right isomerism
Left isomerism

83. 2. Morphological feature of right atrium
Finger like posterior appendage
Smooth surface
Presence of cristae terminalis
D) Septum primum lies on RA side

84. 3. True about right atrial appendage
Narrow based
Triangular
Posterior
None of the above

85. 4.True about ventricular morphology
LV is cresentic in cross section
Moderator band is seen in RV
Trabaculations are less in RV
RV has smooth septal surface

86. 5. Straddling means
Papillary muscle of the valve attached to contralateral ventricle.
Papillary muscle attached to septum
Absence of papillary muscle
Fusion of papillary muscle

87. 6. In d TGA true about connection is
A) AV discordant , VA concordant
B) AV concordant , VA discordant
C) Both AV and VA concordant
D) Both AV and VA discordant

88. 7. In d malposition of great arteries
Aorta posterior and to right
Aorta posterior and to left
Aorta anterior and to right
Aorta anterior and to left

89. 8.Segmental expression of L TGA is
S , D , S
I , L , I
S, D , D
S , L , L

90. false for CAG in dextrocardia
Use JR for LMCA
Clockwise rotation for LMCA
Anticlockwise for RCA

92. THANK YOU