Optimal size of outflow patch in total correction of tetralogy of Fallot.

Hemodynamic and angiocardiographic studies were performed in postoperative patients with tetralogy of Fallot. Pressure gradient between the right ventricle and pulmonary artery was correlated with the narrowest area in the pulmonary arterial pathway. Regurgitant fraction was also correlated with regurgitant area which was determined by preoperative area of the pulmonic annulus and width of the outflow patch. Follow-up study of postoperative patients with tetralogy indicated that those with pressure gradient less than 20 mmHg and regurgitant fraction less than 15% could be considered ideally corrected. A table was constructed for determining the most appropriate width of the outflow patch for the ideal correction.