**2.3 Classification**

In 1988, Carpentier et al. reported the most described morphological classification [11] (**Figure 6**) [7].

#### **Figure 5.**

*Cardiac specimen with Ebstein's anomaly and pulmonary atresia and a specimen with congenitally corrected transposition of the great arteries and an Ebsteinoid anomaly. (a) Shows the right side of a markedly dilated heart with Ebstein's anomaly with failure of delamination of the septal leaflet and pulmonary valvar atresia. (b) Shows the outlet component of this heart showing the dysplastic leaflets of the atrioventricular valve and pulmonary valvar atresia. (c) Shows the septal surface of a left-sided morphologic right ventricle with congenitally corrected transposition of the great arteries (atrioventricular discordant and ventriculo-arterial discordant connections) with an Ebsteinoid anomaly. (Images 5a and 5b used with Robert H. Anderson's permission).*

#### **Figure 6.**

*Carpentier classification of Ebstein's anomaly. RA: right atrium, ARV: atrialized right ventricle; FRV: functional right ventricle (modified with permission from reference [7]).*

Type A: Mild apical displacement of the tricuspid valve leaflets with the adequate functional right ventricle.

Type B: Moderate apical displacement of the tricuspid leaflets with a moderate reduced size but adequate functional right ventricular volume with freely mobile anterior leaflet.

Type C: Severe apical displacement of the tricuspid valve leaflets with a small functional right ventricle. Anterior leaflet movement is restricted due to abnormal chordal attachments that cause right ventricular outflow tract obstruction.

Type D: Complete non-delamination of the tricuspid valve leaflets with almost complete atrialization of the right ventricle, only infundibular portion of the right ventricle remaining: "Tricuspid sac".
