Patent foramen ovale. Persistent foramen ovale.Q21.12 Patent foramen ovale - ICD-10-CM Diagnosis Codes. Large congenital atrial septal defect (ASD) and patent foramen ovale (PFO). Used for patent foramen ovale (PFO) which is a normal variant and for "ruleout" congenital heart disease (CHD). GUIDANCE IN THE USE OF ICD-9-CM. View all the articles associated with any code, right from the code page! View all the articles associated with any code, right from the code page! Open foramen ovale;. The ICD10 and primary and secondary ICF codes associated with neck pain are provided in the 2008 ICFbased neck pain CPG.