Main»Ebsteins Anomaly

Ebsteins Anomaly

Ebstein's Anomaly

1. Morphology

A. Anatomical characterisitics
1) The septal and posterior leaflets of the tricuspic valve are displaced inferiorly towards the RV apex
2) The anterior leaflet is large and sail-like with abnormally numbered and placed chordal attachments
3) The area of right ventricle between the true tricuspid annulus and the displaced attachment of the septal and posterior leaflets is thinned and dilated (atrialized)
4) The remainder of the right ventricular cavity is small
5) The valve leaflets may be adherent to the right ventricular wall
6) The RV infundibulum can be obstructed by the anterior leaflet and/or its chordal attachments
7) The conduction system follows its normal course
8) The anomaly can be right or left-sided
9) Left-sided lesions are usually in the setting of corrected TGA and have a morphologic right-sided valve
B. Carpentier's classification
1) Type A = RV volume is adequate
2) Type B = large atrialized segment of RV; mobile anterior leaflet
3) Type C = restricted movement of anterior leaflet; may cause infundibulum obstruction
4) Type D = near-complete atrialization of the RV (Uhl's syndrome)
C. Associated cardiac anomalies
1) PFO or ASD most common
2) Right ventricular outflow tract obstruction
3) Wolfe-Parkinson-White syndrome

2. Clinical Presentation

A. Contributing factors
1) Severity of tricuspid incompetence
2) Presence of associated atrial septal defect
3) Right ventricle impairment
4) Other cardiac anomalies
5) There is a broad range of symptom severity and age of presentation
B. Neonatal Presentation
1) Worst deformity of valve and RV
2) Tricuspid incompetence accentuated by normal elevated pulmonary resistance
3) Associated pulmonary stenosis or atresia
4) Pulmonary hypoplasia correlated with tricuspid valve incompetence
C. Other Features
1) Right ventricular dysfunction
2) Cardiomegaly, hepatomegaly, ascites, fluid retention
3) Tricuspid valve incompetence
4) Cyanosis
5) Atrial level R to L shunt, polycythemia
6) Paroxysmal tachycardia
7) Wolff-Parkinson-White Syndrome
8) Paradoxical embolus
9) Cerebral abscess
D. Natural History
1) Prognosis is poor with presentation during the first week of life
2) Prognosis improved with presentation after infancy and with mild symptoms
3) Exercise tolerance often reduced
4) Failure to thrive
5) CHF, sudden death, and paradoxical emboli are the three most common causes of death

3. Diagnosis

A. Cyanosis indicates significant right-to-left shunting
B. Palpitations are common
C. Chest X-ray characteristically shows a globular heart from the enlarged right atrium
D. MRI becoming more useful for calculating RV size and function
E. 2-D echocardiography is diagnostic and accurately evaluates the following:
1) RA size
2) tricuspid annulus size
3) function of the valve leaflets
4) evidence of RVOTO
5) presence of PFO or ASD
6) degree of valve incompetence

4. Medical Management

A. PGE for the neonate in extremis
B. General supportive care of cyanotic infants
C. All patients eventually show progressive deterioration and will become possible candidates for surgery

5. Indications for Operation

A. Significant tricuspid valve incompetence
B. Moderate to severe cyanosis with compensatory polycythemia
C. Congestive heart failure (NYHA class III or IV)
D. Extreme cardiomegaly
E. Arrhythmias

6. Operative Technique

A. Tricuspid valve repair is preferred and more likely when repaired early
B. Replace the valve if unable to repair
C. Plicate the atrialized right ventricle
D. Close any associated ASD
E. Consider Maze procedure for atrial arrythmias
F. Interrupt accessory conduction pathways if present

7. Operative Modifications

A. Repair with tricuspid valve replacement
2) The original operation replaced the tricuspid valve with a prosthetic ball valve
3) Current valve replacement is usually done with a mechanical prosthetic valve
B. The Mayo (Danielson) annuloplasty
1) Pledgets placed in ventricle and woven up to level of annulus
2) Sutures tightened to eliminate atrialized portion and form a competent valve
C. Ring annuloplasty
1) Remodels the shape of the annulus to improve valve competence
D. The Carpentier repair
1) Mobilize behind the anterior leaflet and repair any fenestrations or perforations

Video

2) Vertically plicate of the atrialized portion

Video

Video

3) This approach has less tension and reduces the diameter of the tricuspid annulus
4) Advance the anterior leaflet across the plicated area to cover the orifice

Video

5) Placement of an annular ring supports the repair

Video

E. The Quaegebeur repair
1) Similar to Carpentier repair; annuloplasty ring is omitted
F. The Starnes operation
1) Neonates in extremis may require urgent intervention
2) The ASD is enlarged by excising all of the septum primum
3) The tricuspid valve is closed with a pericardial patch
4) The right atrium is plicated
5) A systemic-pulmonary shunt is created
6) If right ventricular function is inadequate, a Fontan operation may be necessary

8. Results

A. Early (hospital) mortality is about 5%
B. Acute heart failure is the principal cause of early mortality
C. Late death is uncommon
D. Consider bidirectional Glenn shunt in paitents with decreased RV function
E. The tricuspid valve is usually competent or has mild incompetence long-term, with a low rate of reoperation (3-5%)
F. Heart block is uncommon
G. W-P-W cured with surgical interruption
H. NYHA class is I or II in the majority of patients
I. Exercise tolerance and oxygen uptake are improved on maximal exercise testing