This document addresses the transcatheter closure of patent foramen ovale and transcatheter or open left atrial appendage (LAA) closure. Q21.12 Patent foramen ovale - ICD-10-CM Diagnosis Codes.Patent foramen ovale. Q2113, CC, 54 codes, Coronary sinus atrial septal defect. This occurs when the foramen ovale, a normal opening in the heart before birth, fails to close after birth, leading to a patent (open) foramen ovale (PFO). The foramen ovale is a hole in the wall between the left and right atria of every human fetus. This hole allows blood to bypass the fetal lungs. 9 - Acute myocardial infarction, unspecified: PFOs are linked to paradoxical embolisms causing myocardial infarction. Patent foramen ovale (PFO) or hole in the heart, affects millions of people and can cause a stroke. CIED, cardiac implantable electronic device; ICD, implantable cardioverter-defibrillator; MR, magnetic resonance; RF, radiofrequency.