Tricuspid Valve Abnormalities

Question 1

What is tricuspid atresia?

Answer 1

A form of congenital heart disease characterized by atresia of the tricuspid valve leading to an absence of right atrioventricular connection and a hypoplastic right ventricle.

Patients often have an atrial septal defect and potentially abnormal arterial connections.

Question 2

What is the consequence of tricuspid atresia on the right ventricle?

Answer 2

Hypoplastic right ventricle.

This occurs due to the absence of a functional tricuspid valve.

Question 3

What type of shunt is associated with tricuspid atresia?

Answer 3

Obligatory right to left shunt.

This is due to systemic venous return being unable to cross the atretic tricuspid valve.

Question 4

What is Tricuspid Atresia with Normally Related Great Vessels (TA with NRGV)?

Answer 4

A condition where the pulmonary artery arises from the hypoplastic right ventricle and the aorta from the left ventricle.

A ventricular septal defect is necessary for blood flow to the lungs.

Question 5

What role does a ventricular septal defect (VSD) play in TA with NRGV?

Answer 5

Ensures flow into the hypoplastic right ventricular chamber and subsequently to the lungs.

A VSD can be bulboventricular foramen.

Question 6

What can occur if the VSD in TA with NRGV is too large?

Answer 6

Pulmonary overcirculation.

This results from excessive blood flow to the lungs.

Question 7

What can occur if the VSD in TA with NRGV is too small?

Answer 7

Cyanosis.

This is due to insufficient pulmonary blood flow.

Question 8

What is Tricuspid Atresia with Transposition of the Great Arteries (TA/TGA)?

Answer 8

A variant where the aorta and pulmonary artery are transposed, with the aorta arising from the hypoplastic right ventricle.

The pulmonary artery arises from the left ventricle.

Question 9

What is required for flow in TA/TGA?

Answer 9

A ventricular septal defect (VSD).

This allows blood to flow into the hypoplastic right ventricular chamber for systemic circulation.

Question 10

What may result from a small restrictive VSD in TA/TGA?

Answer 10

Systemic hypoperfusion.

This can be associated with other left-sided obstructive lesions.

Question 11

What is a possible consequence of the pulmonary artery arising from the left ventricle in TA/TGA?

Answer 11

Pulmonary overcirculation.

This occurs due to unrestricted pulmonary blood flow from the systemic left ventricle.

Question 12

What is Ebstein anomaly?

Answer 12

A rare form of congenital heart disease with apically displaced tricuspid valve annulus causing heart failure

It involves abnormal development of the tricuspid valve leading to right ventricular dysfunction.

Question 13

What causes the annular displacement in Ebstein anomaly?

Answer 13

Failure of the septal and posterior leaflets of the tricuspid valve to delaminate from the myocardium during development

This results in atrialization of the right ventricle.

Question 14

What is the appearance of the anterior tricuspid valve leaflet in Ebstein anomaly?

Answer 14

Often redundant and described as ‘sail-like’

This contributes to the unbalanced deformation of the tricuspid valve.

Question 15

What is the consequence of the rotational displacement of the tricuspid valve?

Answer 15

Causes obstruction in the right ventricular outflow tract (RVOT)

The severity of RVOT obstruction varies among patients.

Question 16

What factors determine the severity of Ebstein anomaly?

Answer 16

Degree of valve displacement, atrialized RV, RVOT obstruction, and ventricular dysfunction

These factors influence clinical presentation and outcomes.

Question 17

When can the initial presentation of Ebstein anomaly occur?

Answer 17

From prenatal to late adulthood

This variability can complicate diagnosis.

Question 18

What is the prevalence of Ebstein anomaly?

Answer 18

Described as 0.5-24 per 100,000 live births

The prevalence is equally distributed among genders.

Question 19

What are common associated cardiac lesions with Ebstein anomaly?

Answer 19

• Atrial septal defect
• Pulmonary stenosis or atresia
• Left sided lesions such as subaortic stenosis, bicuspid aortic valve, or left ventricular dysfunction

The associated lesions depend on the severity of RV compression.

Question 20

What percentage of patients with Ebstein anomaly have accessory pathways leading to ventricular pre-excitation?

Answer 20

Up to 30% of patients

This can lead to arrhythmias.

Question 21

What type of inheritance is suggested to be multifactorial?

Answer 21

Inheritance is likely multifactorial

Affected by genetic, environmental, and reproductive exposures

Question 22

What was initially thought to be associated with maternal lithium exposure during early pregnancy?

Answer 22

Marked increase in risk of Ebstein

This association has been reevaluated in newer studies

Question 23

What do newer studies suggest about the impact of maternal lithium exposure on Ebstein risk?

Answer 23

Demonstrated a lesser impact

This contrasts with earlier beliefs regarding the risk increase

Question 24

What factors does physiology depend on in the context of RVOT obstruction/pulmonary stenosis?

Answer 24

Severity of the RVOT obstruction/pulmonary stenosis, degree of atrialized RV, and RV dysfunction.

These factors significantly influence the clinical presentation and management of the condition.

Question 25

What clinical presentation is associated with severe pulmonary stenosis or pulmonary atresia at birth?

Answer 25

Cyanosis with retrograde filling of the branch pulmonary arteries from the patent ductus arteriosus. ## Footnote This presentation occurs despite the absence of prograde flow across the pulmonary valve.

Question 26

Can pulmonary regurgitation occur in functional pulmonary atresia?

Answer 26

Yes, there can be pulmonary regurgitation in functional pulmonary atresia. ## Footnote This is notable despite the lack of prograde flow across the pulmonary valve.

Question 27

What is the risk associated with patients demonstrating circular shunt physiology?

Answer 27

High risk of rapid deterioration in utero or neonatally with a guarded outcome. ## Footnote This occurs in the presence of severe tricuspid regurgitation and right-to-left flow across the atrial septal defect.

Question 28

What are the components of the circular shunt physiology described?

Answer 28

* Severe tricuspid regurgitation * Right-to-left flow across the atrial septal defect * Prograde flow through the left ventricular outflow tract * Retrograde flow from the patent ductus arteriosus into the MPA * Severe pulmonary regurgitation with flow back into the right ventricle. ## Footnote Each component contributes to the complexity and severity of the patient's condition.

Question 29

What does the severity of Ebstein anomaly depend on?

Answer 29

The degree of RV atrialization. ## Footnote This degree dictates the amount of RV dilation and dysfunction.

Question 30

What can a severely atrialized right ventricle lead to in utero?

Answer 30

Pulmonary valve hypoplasia/atresia. ## Footnote This occurs due to the inability to generate the appropriate degree of antegrade flow.

Question 31

What does RV dysfunction vary from in the neonatal period?

Answer 31

Inability to generate prograde flow across the pulmonary valve to a reasonably well-developed pulmonary valve and branch pulmonary arteries. ## Footnote This variation encompasses the spectrum of severity in RV dysfunction.

Question 32

What is the index of apical displacement of the septal leaflet of the tricuspid valve indicative of?

Answer 32

An index of ≥8mm/m2 is supportive of the diagnosis of Ebstein anomaly ## Footnote Measurement obtained in the apical 4-chamber view in either systole or diastole and divided by patient’s BSA.

Question 33

What morphological features are assessed in the tricuspid valve?

Answer 33

Morphology includes: * Size (Z-score) * Dysplastic thickened and rolled leaflets * Fenestrations * Multiple orifices * Shortened chordae * Underdeveloped papillary muscles * Restricted mobility/tethering * Stenosis ## Footnote These features can indicate various pathologies affecting the tricuspid valve.

Question 34

How is tricuspid regurgitation assessed?

Answer 34

Assessment is done by color and Spectral Doppler ## Footnote Quantification can be difficult due to compliance of the atrialized RV and multiple jets of regurgitation.

Question 35

What is the normal value for maximal velocity across the tricuspid valve?

Answer 35

Normal <0.8 meters/sec ## Footnote This is used to assess for tricuspid stenosis.

Question 36

What should be assessed in the presence of pulmonary stenosis?

Answer 36

Flow and degree of pulmonary valve hypoplasia as well as size of: * MPA * Branch pulmonary arteries ## Footnote MPA refers to the main pulmonary artery.

Question 37

What indicates functional pulmonary atresia?

Answer 37

Presence of pulmonary valve regurgitation (PR) ## Footnote Along with severity of RVOT obstruction.

Question 38

What can help determine the adequacy of pulmonary valve prograde flow?

Answer 38

The direction of flow across a patent ductus arteriosus ## Footnote This is important when assessing pulmonary atresia.

Question 39

What is the significance of assessing for a PFO/ASD?

Answer 39

Presence and direction of flow across an atrial septal defect or PFO can indicate risk of: * Circular shunt * Paradoxical emboli ## Footnote PFO refers to patent foramen ovale and ASD refers to atrial septal defect.

Question 40

What is required to assess for circular shunt physiology?

Answer 40

Presence of: * Severe TR * PFO/ASD * PDA * Pulmonary regurgitation ## Footnote TR refers to tricuspid regurgitation and PDA refers to patent ductus arteriosus.

Question 41

What indices are important when evaluating RV size and function?

Answer 41

Tei index and fractional area change ## Footnote These indices help assess the effect on the interventricular septum.

Question 42

What is the formula for calculating Chamber Area Ratio?

Answer 42

Chamber Area Ratio = (RA + aRV)/(RV + LA + LV) ## Footnote RA = Area of the right atrium, aRV = Area of atrialized portion of RV, RV = Area of the right ventricle, LV = Area of the left ventricle, LA = Area of the left atrium.

Question 43

What does a Chamber Area Ratio of ≥1 in a neonate indicate?

Answer 43

A very poor prognosis ## Footnote This ratio is calculated at end diastole in the apical 4 chamber view.

Question 44

What is Type A in the Carpenter Classification system?

Answer 44

Adequate volume of the true RV. ## Footnote RV stands for right ventricle.

Question 45

Describe Type B in the Carpenter Classification system.

Answer 45

Large atrialized portion of the RV with freely mobile anterior leaflet. ## Footnote The anterior leaflet refers to a part of the heart valve structure.

Question 46

What characterizes Type C in the Carpenter Classification system?

Answer 46

Restrictive mobility of the anterior leaflet. ## Footnote Restrictive mobility indicates limited movement of the heart valve.

Question 47

What is the defining feature of Type D in the Carpenter Classification system?

Answer 47

Almost complete atrialization of the RV. ## Footnote Atrialization refers to the transformation of the ventricular structure towards an atrial form.

Question 48

What does the Celermajer Scoring system (GOSE) measure?

Answer 48

It measures the ratio of (Right atrium + atrialized RV) to (Functional RV + left atrium + left ventricle) based on combined area ## Footnote GOSE stands for the Global Overall Score of the Echocardiogram.

Question 49

What is the grade for a Celermajer score less than 0.5?

Answer 49

Grade 1 ## Footnote This indicates a relatively low level of impairment.

Question 50

What range corresponds to Grade 2 in the Celermajer Scoring system?

Answer 50

0.5-0.99 ## Footnote This indicates a moderate level of impairment.

Question 51

What is the Celermajer score for Grade 3?

Answer 51

1.0-1.49 ## Footnote This indicates a significant level of impairment.

Question 52

What is the threshold for Grade 4 in the Celermajer Scoring system?

Answer 52

>1.5 ## Footnote This indicates a severe level of impairment.