Ebstein's malformation. Surgical treatment and results

Ebstein's malformation can be defined as an anomaly of the tricuspid valve existing in the setting of a right ventricular dysfunction. The technique i ntroduced by Carpentier in 1980 is based on the concept of mobilization of the restrictive anterosuperior leaflet associated with a longitudinal plica tion of the inlet component of the right ventricle. From January 1980 to De cember 1999, 142 patients underwent surgery. The mean age was 25 +/- 15 yea rs (1-65). Cyanosis was present in 48% and associated lesions in 64% of the patients. Patients were classified using a functional approach according t o the severity of the lesions. Mild displacement of the septal leaflet, alo ng with small size of the atrialized chamber was seen in 5% (referred to as Type A). Massive displacement of the septal leaflet, but with normal motio n of the anterosuperior leaflet and an extensive atrialized chamber, was se en in 35% (Type B). In 51%, the mural (inferior) leaflet was absent, the an terosuperior leaflet was severely restricted by muscular trabeculations and very short tendinous cords, and the anterolateral papillary muscle was inc orporated in the right ventricular wall. In these patients (Type C), the at rialized chamber was markedly enlarged and had dyskinetic walls. In such ca ses, the contractility of the distal (functional) right ventricle was also impaired, and some degree of stenosis of the tricuspid valve was present in one-fifth of them. In the most severe cases (8%), the leaflet tissue of th e valve was extremely reduced and the right ventricular walls were thin and contracted poorly. This resulted in the so-called tricuspid sack arrangeme nt (Type D). Valve replacement was needed in only 4 cases, with conservativ e surgery being achieved in 138 patients by means of mobilization of the an terosuperior leaflet and longitudinal plication of the inlet component of t he right ventricle. Additional procedures included the use of a prosthetic ring (94 patients) and partial Glenn anastomosis (30 patients). The hospita l mortality was 10%, mainly due to acute postoperative right ventricular fa ilure. Actuarial survival was 75% at 10 years. After operation, 94% of the patients were in functional class I or II of the New York Heart Association , and 88% had no or mild tricuspid valve insufficiency as judged by echocar diography. The rate of reoperation was 9% with a mean delay of 3 years. A s econd repair was performed in 5 patients. Freedom from reoperation was 87% at 10 years. Sinus rhythm was present in 81%, and 8 pacemaker devices were implanted, 5 for surgically induced atrioventricular block, and 3 because o f preoperative conduction disturbances. The use of the partial Glenn anasto mosis was introduced recently in cases where the right ventricular contract ility was severely impaired, and/or tricuspid valve repair was difficult, a nd/or permanent atrial fibrillation was present. In those patients with hig h risk, adding partial Glenn anastomosis reduced the operative mortality fr om 24% to 6%. Another benefit of the cavo-bipulmonary anastomosis was bette r functional tolerance of mild residual tricuspid valve incompetence. Those patients with the tricuspid sack arrangement had a high rate of reoperatio n (2/11) and valve replacement (3/11), but suffered no operative deaths. We conclude that tricuspid valvoplasty associated with longitudinal right ven tricular plication is superior to valve replacement. The arrangement produc ing a tricuspid sack is not suitable for conservative surgery. An associate d cavo-pulmonary anastomosis decreases the operative mortality in patients at high risk, and seems to preserve right ventricular function.