Tricuspid atresia with l-transposition

Five cases of tricuspid atresia with the rare association of l-transposition are reported. In one case, classical ventricular inversion was present (bulboventricular inversion) and the tricuspid atresia involved the left A-V valve. In the remaining four cases, only the outflow portions of the ventricles were inverted (isolated bulbar inversion). The atretic tricuspid valve was right-sided. In addition to documenting rare anatomic states, this report identifies unusual electrocardiographic findings in tricuspid atresia. Of two of four cases with atresia of the right A-V valve, the electrocardiogram showed right axis deviation (+110°) in one and a normal axis (+75°) in another.