Since herniation and strangulation ofleft atrial appendage or herniation ofLA/LV may occur
Foraminal defect requires surgery
Cardiac MalpositionsHeterotaxySyndromes
Cardiac MalpositionsHeterotaxySyndromes
Trilobed and Bilobed Lungs
Trilobedlung
Liver
Bilobedlung
Spleen
Naming Rules
Since anatomic side (i.e. “left” or“right”) in complex lesions is frequentlyreversed or indeterminate
Naming conventions for
Atria
AV valves
Ventricles
Ventricular outflow tracts
The RulesHow the atria are named
Anatomic right atrium is on side of trilobedlung and liver
Shape of atrial appendage-broad and pyramidal
Same side as IVC
Anatomic left atrium is on side of bilobedlung and spleen
Shape of atrial appendage-thin c narrow neck
Same side as aortic arch
The RulesHow the ventricles are named
Anatomic right ventricle is trabeculatedventricle
Coarse in both systole and diastole
Has tricuspid AV valve
Anatomic left ventricle is smooth-walledventricle
In diastole; fine trabeculations in systole
Has bicuspid AV valve
Anatomic Ventricles
Trabeculated ventricle-Anatomic Right
Smooth ventricle-Anatomic Left
The RulesMitral and tricuspid valves
Tricuspid valve belongs to anatomicright ventricle
Not right atrium
Mitral valve belongs to anatomic leftventricle
Not left atrium
AV ConnectionsConcordance
Ventricles are concordant to the atria
When R atrium connects to R ventricle
L atrium connects to L ventricle
Ventricles are discordant to the atria
When R atrium connects to L ventricle
When L atrium connects to R ventricle
With atrial isomerism, AV connectionsare ambiguous
The RulesAortic and pulmonic valves
Pulmonic valve is part of pulmonaryartery
Not anatomic right ventricle
Aortic valve is part of aorta
Not anatomic left ventricle
Pulmonic infundibulum is part ofanatomic right ventricle
Anatomic Ratrium is onside of trilobedlung-same sideas IVC
Anatomic Latrium is onside of bilobedlung-same sideas Ao arch
Anatomic Rventricle istrabeculated
Anatomic Lventricle issmooth
Tricuspid valvebelongs toanatomic RV
Mitral valvebelongs toanatomic LV
Pulmonic valvebelongs topulmonaryartery
Aortic valvebelongs toaorta
Pulmonicinfundibulumbelongs toanatomic RV
SitusDefinitions
Describes position ofasymmetric organs in body
Lungs
Liver
Spleen
Stomach
Situs Solitus
Normal anatomic relationships
Right sideLeft side
Trilobed lungBilobed lung
Eparterial bronchusHyparterial bronchus
Anatomic right atriumAnatomic left atrium
LiverSpleen
Situs Solitus
Situs SolitusHyparterial/Eparterial Bronchi
Eparterial bronchus-
First branch of Rightmainstem bronchusis above pulmonaryartery
Hyparterialbronchus-
First branch of Leftmainstem bronchusis below pulmonaryartery
Situs Solitus0.6 - 0.8% CHD
Situs Inversus
Reversed anatomic relationships
Right sideLeft side
Bilobed lungTrilobed lung
Hyparterial bronchusEparterial bronchus
Anatomic left atriumAnatomic right atrium
SpleenLiver
Situs Inversus
Situs Ambiguous
Lungs and abdomen are symmetric soright and left sides can’t be defined
Isomerism-both atria have the samefeatures
Either right or left
Two kinds of situs ambiguous
Bilateral right-sidedness
Bilateral left-sidedness
Situs AmbiguousHeterotaxy Syndrome
Bilateral right-sidedness
Since, spleen is usually on left side
No spleen
Asplenia syndrome
Bilateral left-sidedness
Since, spleen is usually on left side
Many spleens
Polysplenia syndrome
Situs Ambiguous
Cardiac Positions
Position of cardiac apex
Levocardiaon the left
Dextrocardiaon the right
Mesocardiain the midline
Cardiac malposition
Anything other than situs solitus withlevocardia
Rule of Thumb
If aortic arch/apex ofheart are on oppositesides from stomachbubble, highincidence of CHD
Cardiac MalpositionsTypes
Situs solitus with dextrocardia
Situs inversus with levocardia
Situs inversus with dextrocardia
Situs Solitus with Dextrocardia
95% chance of CHD of which 80% corrected transpositionIf cyanotic with flow, then tricuspid atresia.If cyanotic with flow, then corrected transposition.If asplenia, then 100% have common ventricle.Interrupted IVC common.
Bilobed lung
Spleen
Trilobed lung
Liver
Situs Solitus with DextrocardiaCoarctation of Aorta
Situs Inversus with Levocardia
Rare, but 100% CHDIf asplenia, 100% have common ventricleInterruption of IVC common
Trilobed lung
Liver
Bilobed lung
Spleen
Situs Inversus with Levocardia
Situs Inversus with LevocardiaTransposition
Situs Inversus with Dextrocardia
3-5% CHDMost common is Corrected TranspositionKartgener’s
Trilobed lung
Liver
Bilobed lung
Spleen
Situs Inversus with Dextrocardia
S
Trilobed lung
Situs SolitusMalposition of the Stomach
R/O aspleniaMost have CHD (L R shunt)Those with polysplenia have azygous continuation of IVC
Bilobed lung
Liver
Trilobed lung
Spleen
Situs Solitus with Malposition of the Stomach
Situs InversusMalposition of the Stomach
Situs Inversus with Malposition of the Stomach95% CHD of which 80% are Corrected Transposition
Trilobed lung
Spleen
Bilobed lung
Liver
Situs AmbiguousHeterotaxy Syndrome
Bilateral right-sidedness
Since, liver is usually on right side
No spleen
Asplenia syndrome
Bilateral left-sidedness
Since, spleen is usually on left side
Multiple spleens
Polysplenia syndrome
AspleniaBilateral Right-sidedness
Male
Cyanotic
High risk of infection
Severe cardiac abnormalities
Transposition
TAPVR
Female
Abnormalities are more benign
Azygous continuation of IVC
Bilateral superior vena cava
PAPVR
ASD
PolyspleniaBilateral left-sidedness
Asplenia/Polysplenia
Asplenia – bad boy
Polysplenia – good girl
Situs Ambiguous-polysplenia
Approach to Cardiac Malpositions
Which side is heart on
Which side is trilobed lung on
Which side is arch on
Which side is stomach bubble on
Check for asplenia
Midline liver
Minor fissures in both lungs
Situs Inversus with Levocardia
Rare, but 100% CHDIf asplenia, 100% have common ventricleInterruption of IVC common