Ebstein’s Malformation With Imperforate Tricuspid Valve
A neonate was admitted at the age of 8 days with a history of increasing cyanosis and tachydyspnea after a normal pregnancy and delivery at 42 weeks’ gestation. A transthoracic echocardiography appeared to indicate pulmonary atresia with an intact ventricular septum. The child was intubated, intravenous prostaglandin E1 was started, and the patient was transferred to our hospital.
The newborn presented with central cyanosis while being ventilated with 100% oxygen. No heart murmur was perceptible. Transthoracic echocardiography revealed marked apical displacement of the tricuspid valve leaflets (Figure 1 and Movie I). Linear attachments of the anterior and the mural leaflets resulted in complete separation of the inlet portion from the apical trabecular and outlet portions of the right ventricle (Figure 2 and Movie II). On color Doppler, we were unable to demonstrate either antegrade or regurgitant flow across the valve (Figure 3 and Movie III). There was a restrictive apical muscular ventricular septal defect with shunting from the left to the distal right ventricle, resulting in some antegrade flow in the right ventricular outflow tract (Figures 3, 4, 5, and 6⇓⇓⇓ and Movies III, IV, V, and VI). There was no Doppler gradient across the right ventricular outflow tract, and the pulmonary valve, although small, appeared morphologically normal. Under therapy with prostaglandin E1, there was left-to-right shunting across the patent ductus arteriosus. There also was a patent foramen ovale with right-to-left shunting at the atrial level. The patient underwent placement of a central aortopulmonary shunt (4-mm polytetrafluoroethylene prosthesis), resection of the interatrial septum, and clip closure of the ductus arteriosus. Because malformation of the tricuspid valve and hypoplasia of the right ventricle precluded biventricular repair, the child underwent bidirectional Glenn anastomosis at the age of 5 months as a first step for a later Fontan-type palliation.
Ebstein’s malformation is an uncommon congenital heart disease with great variability in the morphology of the tricuspid valve. In the majority of cases, dysplasia and displacement of the tricuspid valve leaflets result in varying degrees of tricuspid regurgitation. In some hearts, however, there may be linear attachments of the anterosuperior and mural leaflets to the junction between the inlet and trabecular components of the right ventricle, resulting in the so-called imperforate type of Ebstein’s malformation with functional tricuspid atresia.
Tethering and displacement of the tricuspid leaflets result in a very peculiar echocardiographic appearance, with an “empty” tricuspid annulus and membranous separation of the inflow and the outflow portions of the right ventricle. In patients with intact ventricular septum, there will be associated pulmonary atresia; in our patient, the muscular ventricular septal defect allowed some antegrade flow across the pulmonary valve. Although imperforate Ebstein’s anomaly has been well described in pathological series, to the best of our knowledge, this is the first report describing the transthoracic echocardiographic appearance of this rare malformation.
The online-only Data Supplement, consisting of Movies I through VI, is available with this article at http://circ.ahajournals.org/cgi/content/ full/115/6/e177/DC1.