Ebstein's malformation of the tricuspid valve. A review of 65 cases

Echocardiographic spectrum of Ebstein's anomaly of the tricuspid valve

Sixteen patients aged between one day to 18 years with Ebstein's malformation of the tricuspid valve were studied with ultrasound. The findings were compared with a group of 74 patients without Ebstein's malformation. Two features were considered specific for Ebstein's malformation: 1) ability to record the anterior tricuspid leaflet (ATL) farther to the left of the left sternal border than in the control group; and 2) abnormally prolonged interval between the "C" points of the tricuspid and the mitral valve echoes (McTcI). All other parameters measured were nonspecific for Ebstein's anomaly of the tricuspid valve. The sail sound was recorded in ten patients with Ebstein's malformation and occurred at the time when the anterior tricuspid leaflet was in the most posterior position. In a patient with congenital heart disease, an McTc interval greater than 0.03 sec and recording of an anterior tricuspid leaflet near the apex of the heart strongly suggest the diagnosis of Ebstein's malformation. These two criteria were not fulfilled in any patient who did not have Ebstein's malformation. Conversely, however, absence of these two features does not rule out Ebstein's anomaly of the tricuspid valve.

Electrophysiologic characteristics of Ebstein's anomaly of the tricuspid valve

Electrophysiologic characteristics of five patients with Ebstein's anomaly of the tricuspid valve were defined with studies using luminal intracardiac electrode catheters. The diagnosis was made in each case from clinical data and confirmed at cardiac catheterization by the presence of an atrialized right ventricular chamber with atrial mechanical activity and ventricular electrical activity. In three cases intra-right atrial conduction was prolonged (P-A intervals of 50, 50, and 65 msec), a finding which reflected the presence of a characteristically large right atrium. The bundle of His electrogram was recorded in its usual anatomical location. Atrioventricular nodal conduction was prolonged in only one case. Intra-His delay was observed in two cases (bundle of His duration of 30 and 30 msec). Infranodal conduction was prolonged in four cases with H-V intervals of 60, 65, 65, and 80 msec. The anatomical abnormalities were least severe in the only patient with a normal H-V interval (50 msec). The prolonged H-V interval was thought to result from stretching of the conduction system over the atrialized right ventricle (ARV). The late depolarization during the splintered R' of the electrocardiogram found during intracardiac mapping of the ARV in three patients confirms the theory that the ARV produces the "second QRS" typically seen in this anomaly. The ARV was particularly irritable, and ventricular fibrillation was produced in two patients during catheter manipulation in this area. In one case the ARV had a shorter refractory period than the body of the right ventricle. Re-entrant supraventricular tachycardia was induced in the only patient with Wolff-Parkinson-White syndrome. In addition to the previously recognized electrophysiologic features reconfirmed here, patients with Ebstein's anomaly of the tricuspid valve usually have: normal position of the bundle of His, prolonged intra- right atrial conduction, prolonged infranodal conduction, and irritable ARV with delayed activation.

Ebstein's anomaly associated with a definite atrial left to right shunt--case report

A case with Ebstein's anomaly associated with large left to right atrial shunt was operated upon. The patient did not demonstrate any tricuspid insufficiency in spite of the downward displacement of the septal and posterior leaflets of tricuspid valve. The surgical closure of the atrial septal defect relieved the impending heart failure. The pulmonary congestion disappeared but the cardiomegaly persisted after the operation.