Congenital heart disease includes a wide range of heart defects that appear at birth, corresponding to the most frequent group of genetic alterations. They represent the most frequent birth defects in the world, affecting millions of newborns annually. Chile is not exempt from this public health problem, estimating a prevalence of 8-10 per 1,000 live births, similar to international figures. Some of these defects are not diagnosed in a timely manner due to various causes, including causes such as poor clinical translation and limited accessibility to the Public Health system. Thanks to the improvement of technological resources, more cases of congenital heart disease are diagnosed every day and the time of diagnosis is getting earlier. The case presented below refers to a 47-year-old male patient with several comorbidities, who underwent a Doppler echocardiogram during his hospitalization due to acute respiratory failure, where a systodiastolic flow was detected in one of the compatible pulmonary arteries, with a patent ductus arteriosus.