Patent foramen ovale. Persistent foramen ovale.Q21.12 Patent foramen ovale - ICD-10-CM Diagnosis Codes. Atrial septal defect, unspecified. Q2111, Secundum atrial septal defect. A condition in which the foramen ovale in the atrial septum fails to close shortly after birth. Q2113, CC, 54 codes, Coronary sinus atrial septal defect. Were largely benign, without sign of patent foramen ovale or overt embolic nidus. NCP Nutrition in Clinical Practice. Volume 33 • Number 4 • August 2018.