A case of a week old female baby, admitted because of apathy, hypothermia, dyspnea, jaundice and cyanosis is described. She had the characteristic phenotype of Turner's syndrome with normal karyotype. Signs of severe heart failure were present. Therapy with diuretics, digoxin, dopamine and mechanical ventilation were unsuccessful, and the patient died several hours after her admission. The anatomopathological examination revealed the presence of hypoplastic left heart syndrome with mitral atresia and aortic atresia, atrial septal defect, double outlet right ventricle, and a patent ductus arteriosus.