Angiocardiographic quantitative evaluation of double-outlet right ventricle: special reference to the morphology of the common outflow tract.

Geometrical measurements of angiocardiograms of the common outflow tract (COT) of 13 patients were made to determine in which cases internal conduit repair was feasible, and under which conditions a patch enlargement of the COT was indicated. In the pulmonary stenosis (PS) group, the area of the narrowest cross-section of the COT was significantly smaller than that in the pulmonary hypertension (PH) group (p less than 0.025). In the PS group, the area was rarely sufficient to be shared by systemic and pulmonary circulation. Therefore, stenosis in the outflow tract to the pulmonary artery will occur if the intraventricular tunnel technique is applied, without patch enlargement of this portion, to patients with PS. On the contrary, the cross-sectional areas of the COT and pulmonary arteries were significantly larger in the PH group than in the PS group. Accordingly, the intracardiac conduit operation may be possible in such patients without a patch enlargement, even in young patients if other intracardiac conditions allow. Preoperative angiocardiographic evaluation of the COT is helpful in preoperatively selecting the proper operative procedure for this anomaly.