In situ placement of a valved conduit at the pulmonary annulus.

The technique of repair of pulmonary atresia with intact ventricular septum is described. The porcine valved conduit (Hancock) was placed so that the valve was in the "anatomic" position, avoiding compression by the sternum. There was a mild gradient (15 mm. Hg) at a cardiac index of 4 L. per minute per square meter across the porcine valve itself, measured at the postoperative catheterization. The valve orifice diameter was only 15 mm., which is considerably less than the 22 mm. valve annulus. The possible merits of this procedure over the conventionally placed valved conduit and over an outflow tract patch are discussed.