Transatrial resection of the obstructed right ventricular infundibulum.

Obstructions of the right ventricular infundibulum were resected through the orifice of the tricuspid valve in 21 patients, 15 of whom had tetralogy of Fallot. At operation the systolic pressure difference between the right ventricle and pulmonary artery after repair averaged 18 mm Hg (range 0-40 mm Hg). In patients with tetralogy, cardiac index four hours after operation averaged 2.8 L/M2/min. One patient with tetralogy and severe pulmonary hypertension died. Twelve patients with tetralogy were recatheterized 10 to 186 days after operation. The mean systolic pressure difference between right ventricle and pulmonary artery was 23 mm Hg. Residual obstructions were in the pulmonary valvular annulus. Cineangiograms did not show paradoxical motion of the right ventricular wall. Transatrial resection of right ventricular infundibular obstructions carries with it none of the consequences that often follow right ventriculotomy and this surgical approach satisfactorily relieves infundibular obstructions.