Ebstein Anamoly

Ebstein anomaly is a congenital heart defect in which the septal leaflet of the tricuspid valve is displaced towards the apex of the right ventricle of the heart.Tricuspid valve malformed and displaced downwards with atrialization of right ventricle and florid tricuspid incompetence. Right ventricular cavity is small, and there is interitrial communication through persistent foremen ovale.

Presentation in Ebstein Anomaly

a) Infancy              :         Cyanosis, CHF

b) Childhood         :         Exterional dysphoea, fatigue and weakness.

The annulus of the valve is still in the normal position. The valve leaflets, however, are to a varying degree, attached to the walls and septum of the right ventricle. There is subsequent ‘atrialization’ of a portion of the morphologic right ventricle (which is then contiguous with the right atrium). This causes the right atrium to be large and the anatomic right ventricle to be small in size.
S3 heart sound
S4 heart sound
Systolic murmur of tricuspid regurgitation
Mid-diastolic murmur along the lower left sternal border
Right atrial hypertrophy
Right ventricular conduction defects
Wolff-Parkinson-White syndrome often accompanies

Diagnosis of Ebstein Anomaly

Physical Examination findings

Cyanosis

Intermittent in 50 percent

Persistent in 30 percent

Absent in 20 percent

JVP normal even in presence of florid tricuspid regurgitation due to dampening effect of large right atrium.

S1 is widely split with accentuated tricuspid component

S2 Variable

S3, S4 common.

All heart sounds may summate

Pan systolic murmur of tricuspid regurgitation

X-Ray findings

                Enlarged RA

Pulmonary oligemia if cyanotic

ECG findings

Giant P wave,  P-R prolongation

RBBB often bizarre and atypical

WPW in one fourth cases

Episodes of SVT in one third

Other abnormalities that can be seen on the ECG includes (1) signs of right atrial enlargement or tall and broad ‘Himalayan’ P waves, (2) first degree atrioventricular block manifesting as a prolonged PR-interval, (3) low amplitude QRS complexes in the right precordial leads, (4) atypical right bundle branch block, (5) T wave inversion in V1-V4 and Q waves in V1-V4 and II, III and aVF

Echo findings

             Shows displacement and deformity of tricuspid valve

Colour flow detects site of right to left shunting

Doppler detects severity of TR

Risk Factors of Ebstein Anomaly

There is an enlargement of the aorta, which may cause an increased risk of abnormality in infants of women taking lithium during the first trimester of pregnancy (though some have questioned this) and in those with Wolff-Parkinson-White syndrome.

Treatment in Ebstein Anamoly

Ebstein’s cardiophysiology typically presents as an (antidromic) AV reentrant tachycardia with associated pre-excitation. In this setting, the preferred pharmacological treatment agent is procainamide. Since AV-blockade may promote conduction over the accessory pathway, drugs like beta blockers, calcium channel blockers and digoxin are contraindicated.
If there is atrial fibrillation with pre-excitation, treatment options include procainamide, flecainide, propafenone, dofetilide and ibutilide since these medications slow conduction in the accessory pathway causing the tachycardia and should be administered before considering electrical cardioversion. Intravenous amiodarone may also convert atrial fibrillation and/or slow the ventricular response.

Surgery options

The Canadian Cardiovascular Society (CCS) recommends surgical intervention for the following indications:[5]
Limited exercise capacity (NYHA III-IV).
Increasing heart size (cardiothoracic ratio greater than 65%).
Important cyanosis (resting oxygen saturation of less than 90%). (Level B)
Severe tricuspid regurgitation with symptoms.
Transient ischemic attack or stroke
The CCS further recommends patients who require operation for Ebstein anomaly should be operated on by congenital heart surgeons who have substantial specific experience and success with this operation. Every effort should be made to preserve the native tricuspid valve