ICD 10 code for Patent foramen ovale. Get free rules, notes, crosswalks, synonyms, history for ICD-10 code Q21.12.Patent foramen ovale. Persistent foramen ovale. Q21.12 Patent foramen ovale - ICD-10-CM Diagnosis Codes. Aims: To identify the prevalence of PFO in patients undergoing TLE, characterize affected patients, and compare incidence of adverse events. 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. ICD-10-PCS procedure codes: Code Description. 02U53JZ. Patent foramen ovale.