Chapter 5

    In this pathology one or more of the pulmonary veins is connected to the right side of the heart. As in the case of total anomalous return, the connection can be located below or above the diaphragm. The association with A.S.D. is very common and in particular, with the sinus venosus type.
    The clinical picture and hemodynamic condition in general depend upon the volume of the anomalous venous return to the right side (more or less than 50% of the lung's blood flow).
    In the case of more than 50% shunting, marked volume overload and hypertrophy of the right ventricle will appear with possible pulmonary hypertension.
    The roentgenogram can depict an anomalous shadow in the right lung (scimitar sign). Enlargement of the right atrium and eventually the right ventricle depend on the shunt volume and pulmonary vascular resistance.
    The same observations are valid for the findings in the electrocardiogram where the potential modifications closely correlate with the shunt importance, degree of right atrial and ventricular enlargement and possible associated pulmonary hypertension.
    The anomalous return can be proven with the entering of the catheter in one of the pulmonary veins and confirmed with blood sampling and oximetry. Dye-dilution studies are helpful also.

Roentgenogram of a patient with Anomalous Venous Return showing the typical Scimitar Sign.