Ebstein’s Anomaly

Ebstein’s Anomaly Steven H. Todman, M.D. Assistant Professor Pediatric Cardiology LSUHSC-Shreveport

Goals and objectives • The learner will understand the anatomy, pathology, genetic factors, associated cardiac defects, presentation, and evaluation and management in children with Ebstein’s Anomaly

Objectives • Embryology • Know the embryologic basis for Ebstein anomaly of the tricuspid valve • Anatomy • Recognize pathologic features of Ebstein anomaly of the tricuspid valve • Recognize lesions commonly associated with Ebstein anomaly of the tricuspid valve • Physiology • Know the spectrum of abnormalities in circulatory physiology and oxygen delivery in Ebstein anomaly of the tricuspid valve

Objectives • Clinical findings • Recognize Ebstein anomaly of the tricuspid valve based on clinical findings • Laboratory findings • Recognize the typical radiologic features of Ebstein anomaly of the tricuspid valve • Diagnose Ebstein anomaly of the tricuspid valve by echocardiography, and recognize important anatomic features • Recognize the typical ECG findings for Ebstein anomaly of the tricuspid valve

Objectives • Management, including complications • Plan medical management of a neonate with Ebstein’sanomaly of the tricuspid valve and severe hypoxemia • Plan appropriate surgical and transcatheter therapy in a patient with Ebstein’sanomaly of the tricuspid valve • Understand ventilatory and metabolic consequences in a severely hypoxemic patient with Ebstein’sanomaly of the tricuspid valve • Manage the surgical complications of Ebstein’sanomaly of the tricuspid valve

Which of the following is false? • (A) The tricuspid valve has three leaflets: anterior, inferior (posterior), and septal. • (B) The leaflets develop from the endocardial cushions exclusively • (C) Ebstein’s anomaly is characterized by adherence of the septal and inferior leaflets to the underlying myocardium. • (D) There is redundancy, fenestrations, and tethering of the anterior leaflet of the tricuspid valve. • (E) There is dilation of the right AV junction (true tricuspid annulus)

Answer • (B) is false. The leaflets of the tricuspid valve develop equally from the endocardial cushion tissues and the myocardium. Downward dysplacement of the tricuspid valve is due to failure of delamination of valve leaflets from underlying myocardium.

Which of the following are false? • (A) The anterior leaflet is usually small, and attached to the tricuspid annulus • (B) The anterior leaflet is generally redundant and may have fenestrations. • (C) Chordaetendineae are generally short and poorly formed. • (D) The anterior leaflet may form a sail-like intracavitary curtain.

Answer • (A) is false. The anterior leaflet is usually the largest leaflet, and it is attached to the tricuspid valve annulus.

Which of the following are false? • (A) In normal hearts, the downward displacement of the septal and posterior leaflets in relation to the anterior mitral valve leaflet is <8mm/m2 body surface area. • (B) There is usually marked dilation of the true TV annulus which is not displaced. • (C) The left coronary artery demarcates the level of the true tricuspid valve annulus. • (D) The right coronary artery is vulnerable to kinking or distortion during RV plication, annuloplasty procedure, or tricuspid valve replacement.

Answer • (C) is false. The right coronary artery is vulnerable to kinking or distortion during RV plication, annuloplasty procedures, or tricuspid valve replacement due to the thin nature of the atrial and ventricular tissue at the level of the AV groove.

Which of the following is false? • (A) The dilation in Ebstein’s anomaly usually involves the atrialized inlet portion of the RV and the right ventricular apex and outflow tract. • (B) The anomaly is more common in twins, in those with a family history of congenital heart defects, and those with a maternal exposure to benzodiazepines. • (C) Maternal lithium exposure is a frequent association with Ebstein’s anomaly.

Answer • (C) Is false. Maternal lithium exposure is not a frequent association with Ebstein’s anomaly.

Which of the following are false? • (A) A PFO or ASD is present in 80-94% of patient’s with Ebstein’s Anomaly. • (B) A VSD is commonly present with or without pulmonary atresia • (C) RVOT obstruction and PDA are commonly seen. • (D) Left sided heart lesions and coarctation of the aorta are often seen. • (E) Accessory conduction pathways are present in 15-20% of patient’s, predisposing them to arrhytmias. • (F) RV noncompaction is frequently seen.

Answer • (F) RV noncompaction is not frequently seen. 39% of 18% of patients had left ventricular dysplasia resembling noncompaction.

Which of the following is false? • (A) The functional impairment of the RV and TV regurgitation retards forward flow of blood through the right side of the heart. • (B) Ebstein’s anomaly can be a ductal dependent lesion • (C) Patients with severe disease will have elevated RA pressure, and significant right to left interatrial shunting, with arterial desaturation. • (D) Patients may present with cyanosis that may worsen as pulmonary vascular resistance decreases. • (E) Patients are often at risk for paradoxical embolization, brain abscesses, and sudden death.

Answer • Patients may present with cyanosis that may improve as pulmonary vascular resistance decreases.

Which of the following are not frequently seen as part of the physical exam of Ebstein’s Anomaly? • (A) Murmur and click • (B) Cyanosis • (C) Prominent “v” wave in the distended jugular veins • (D) Hepatomegaly • (E) Widely split first and second heart sounds • (F) A prominent S3 and/or loud S4 • A systolic murmur at the left lower sternal border that increases with inspiration. • (G) A mid-diastolic murmur

Answer • Prominent “v” wave in the distended jugular veins are usually not present, despite severe regurgitation of the tricuspid valve because the large RA engulfs the increased volume. • Prominent “a” waves, however are seen in the distended jugular veins.

Which of the following are false? • (A) First degree AV block rarely occurs. • (B) Chest radiography shows can show an enlarged globe-shaped heart with a narrow waist, similar to that seen with a pericardial effusion. • (C) Outcome is worse when the cardiothoracic ratio is >0.65 on chest x-ray. • (D) Intra-atrial conduction disturbance including PR interval prolongation and tall P waves can be seen. • (E) A right bundle branch block can be seen.

Answer • First degree AV block frequently occurs.

Which of the following is false? • (A) Apical displacement of the septal leaflet by at least 8 mm/m2 BSA is considered a diagnostic feature of Ebstein’s anomaly. • (B) Important features that can be determined echocardiographically and that can predict outcome in neonates include patency of the RVOT. • (C) Predictors of cardiac-related death include NYHA class III or IV, cyanosis, severe TR and younger age at diagnosis.

Answer • All are true.

Which of the following is false? • (A) Biventricular repair (Knott-Craig Approach) involves a repair of the tricuspid valve, and partial closure of the atrial septum. • (B) Right ventricular exclusion (Starnes Approach) involves fenestrated patch closure of the tricuspid orifice, enlargement of the interatrial communication, right atrial reduction, and placement of a systemic to pulmonary artery shunt. • (C) The RV exclusion procedure is useful for patients with anatomic RVOT obstruction. • (D) Cardiac transplantation is most often utilized when there is significant LV dysfunction.

Answer • All are true.

Which of the following are false? • (A) In mild Ebstein’s anomaly, with nearly normal heart size, and absence of arrhythmias, athletes can participate in all sports. • (B) ACE inhibitors have unproven efficacy in right-sided failure, but they are used frequently as part of a heart failure regimen. • (C) Patients with tachyarrhythmias should undergo EP evaluation and ablation. • (D) Success rate of catheter ablation is equal to those with structurally normal hearts.

Answer • Success rate of catheter ablation is lower than those with structurally normal hearts.

Which of the following is false? • (A) Indications for surgery includes the presence of symptoms, cyanosis, and paradoxical embolization. • (B) In the presence of class III or IV NYHA or significant symptoms, medical treatment has little to offer and the surgery will be the best chance for improvement. • (C) If TV repair is not feasable, porcine bioprosthetic valve replacement is a good alternative over mechanical valves due to the lack of anticoagulation. • (D) The most common atrialtachyarrhytmias in Ebstein’s anomaly are atrial fibrillation and flutter.

Which of the following is false? • (A) Indications for surgery includes the presence of symptoms, cyanosis, and paradoxical embolization. • (B) In the presence of class III or IV NYHA or significant symptoms, medical treatment has little to offer and the surgery will be the best chance for improvement. • (C) If TV repair is not feasable, porcine bioprosthetic valve replacement is a good alternative over mechanical valves due to the lack of anticoagulation, despite increased risk of thrombosis. • (D) The most common atrialtachyarrhytmias in Ebstein’s anomaly are atrial fibrillation and flutter.

Answer • All are true

Which of the following are false? • (A) Optimal timing for surgical repair is before the onset of RV dysfunction even in asymptomatic patients. • (B) When a mechanical valve is used, the target INR is 1.5 to 2.5, in addition to aspirin 81 mg daily. • (C) Uhl’s anomaly is an absence of the myocardial layer of the RV, and generally results in CHF, peripheral edema, and pleural effusion. • (D) Arrhythmias are not common in Uhl’s anomaly. • (E) Uhl’s anomaly is associated with PA/IVS.

Answer • When a mechanical valve is used, the target INR is 3 to 3.5, in addition to aspirin 81 mg daily.

Ebstein’s Anomaly