[Diagnosis of congenital AV fistula in childhood--report of a clinical case].

Pulmonary AV fistulas are rarely diagnosed in children. In the absence of cardiac malformations or chronic lung disorders, cyanosis is the most reliable symptom. The diagnosis is confirmed by a series of complementary investigations such as measurement of arterial blood gases, contrast echocardiography, cardiac radionuclid ventriculography and cardiac catheterization studies. These diagnostic procedures serve as a reliable background for any therapeutic decisions.