[Subaortic stenosis associated with atrioventricular septal defect. A rarely mentioned condition].

White male patient, 14 years old, who developed a severe subaortic stenosis in the late postoperative period of a total correction of atrioventricular septal defect. Clinical diagnosis was confirmed by echocardiography and cardiac catheterization. The patient underwent reoperation for treatment of the new condition, with resection of subaortic stenosis. Atrioventricular septal defects show a narrow and deformed left ventricle outflow tract, susceptible to obstruction before or after operation. It is, therefore, advisable to investigate a possible obstruction before the operation at the operation room and in the late postoperative period.