Over a period of 8 years, 176 cases of cardiac anomalies have been found in over 10,000 consecutive admissions. The place of birth and its altitude have been recorded for each one of these causes. Patent ductus arteriosus and persistent interatrial communications are more likely to be found in patients born at high altitudes. It is suggested, but remains to be shown, that this is true for defects of the pulmonary artery. No apparent relation could be found in this series for other malformations. It is presumed that mechanical factors tied to the pulmonary circulation and the lower oxygen tension both have a decisive influence.

Aun cuando son, relativamente, incompletas nuestras observaciones sobre este tema debido a la escasez de material patológico y a la condición en que el mismo llegó para su estudio, juzgamos conveniente una descripción para animar a otros observadores nuestros a fin de completar el cuadro anatómico. Otra razón más que no simpele a publicar estos apuntes es el de comparar nunestros resultados con los de varios investigadores y notar sus analogías.