Ebstein’s disease is an abnormality of the tricuspid valve in which the septal foil and the posterior foil are shifted to the right ventricular apex and the anterior foil is usually malformed, excessively big and abnormally attached to the right ventricular free wall. Thus, a portion of the right ventricular is “atrialization“ in the portion of the tricuspid valve and the right ventricular fibrillation that remained functional is small. Tricuspid valve is usually regurgitated but may be stenotic. 80% of patients with Ebstein’s disease have an inter-atrial communication (atrial septal defect or patent foramen ovale) that can occur right-left shunting of blood.
The severity of hemodynamic disorders in patients with Ebstein’s disease depends on the movement and the functional status of the tricuspid valve foil. Patients with mild apical displacement of the tricuspid foils have normal valvular function, while those with severe displacement foil attachment have abnormal tricuspid valve or previous valvular dysfunction have increased pressure in the right atrium and are right-to-left inter-atrial. Similarly, the clinical presentation of Ebstein’s disease it is ranges from severe heart failure in the fetus or newborn to absence of symptoms in an adult who is diagnosed incidentally.
When Ebstein’s disease is discovered during fetal life, uterine mortality rate is high. Infants with severe disease have cyanosis, with heart failure and a murmur noted in the first days of life. A transient improvement can occur when pulmonary vascular resistance decreases, but the situation is getting worse by the closure of the ductus arteriosus, thereby decreasing pulmonary blood flow. Older children with Ebstein’s disease often come to consultation due to a blast accidentally discovered while adolescents and adults presenting with supraventricular arrhythmias. In adults with Ebstein’s disease, the most important predictors of prognosis are NYHA functional class, heart size, presence or absence of cyanosis and presence or absence of paroxysmal atrial tachycardias. These tachycardias can lead to heart failure, worsening cyanosis and even syncope. Patients with Ebstein’s disease and inter-atrial communication have a risk of paradoxical embolism, brain abscess and sudden death.
On physical examination, the severity of cyanosis depends on the size from right-to-left. Noises I and II are widely duplicated and noise III or IV are often present, resulting in a rhythm in 3 or 4 strokes. A systolic murmur caused by tricuspid regurgitation is usually present on the left of the sternum. Hepatomegaly (resulting from passive hepatic congestion due to elevated right atrial pressure) may be present.
Where high and wide P’s are common on ECG, and also the right bundle branch block. Atrioventricular block of first degree occurs frequently. Approx. 20% of patients with Ebstein’s disease have a ventricular pre-excitation beam path between the atrium and ventricle accessory (Wolff-Parkinson-White syndrome), and a delta wave may be present.
The radiological data depends on the severity of anatomical anomaly. In mild cases, the size of the heart and pulmonary vasculature are normal. In more severe cases marked cardiomegaly is present, due mostly to the right atrium enlargement. In severe cases (with little functional right ventricular are marked right-left), pulmonary vasculature is low.
Echocardiography is used to assess right atrial dilatation, anatomic displacement and distortion and severity of tricuspid valve regurgitation foil or tricuspid stenosis. In addition can be determined the presence and size of inter-atrial shunting (through the color Doppler and micro-bubble contrast image) as well as associated cardiac abnormalities.
Electrophysiological evaluation is required in patients with atrial tachyarrhythmias.
Ebstein’s disease management focuses on the prevention and treatment of complications. It is recommended prophylaxis against infective endocarditis. Patients with symptomatic heart failure receive diuretics and digoxin. Those with atrial arrhythmias can be treated pharmacologically or with catheter ablation (if present an accessory pathway). Ablation of accessory pathways has a lower success rate in patients with Ebstein’s disease than in those with structurally normal heart and arrhythmia recurrence risk is higher. In children with Ebstein’s disease gravity are creating a systemic arterial circulation to the pulmonary circulation to increase pulmonary blood flow, thus decreasing cyanosis. Subsequent surgery to create a uni-ventricular heart (for example: The Fontan procedure) can also be taken into account in newborns. Repair or replacement of the tricuspid valve in association with inter-atrial communication closure is recommended for older patients who have severe symptoms despite to medical therapy. In addition, repair or replacement should be considered in patients with less severe symptoms which have a heart enlargement because it has a poor prognosis. When possible, valve repair is preferable to valve replacement because it is associated with lower mortality and has fewer long-term complications. However, when it is required valve replacement; a bio-prosthesis is preferable to a mechanical prosthesis. Complications of surgical correction of the Ebstein’s disease include complete atrioventricular block, persistent supraventricular arrhythmias, and residual tricuspid regurgitation after valve repair and prosthetic valve dysfunction.