Anatomy Patent foramen ovale is due to A Failure of closure of sinoatrial orifice B Failure of fusion of septum primum and endocardial cushion C Failure of fusion of septum primum and septum intermedium D Failure of fusion of septum primum and septum secondum 💡 Explanation Patent foramen ovale is due to ✓ Correct Answer: D. Failure of fusion of septum primum and septum secondum