Inferior myocardial infarction is often accompanied by infarction of the right ventricle (RV). Uncommon RV infarction cases with patent foramen ovale (PFO) shunt, leading to severe persistent hypoxemia even without any pulmonary embolism involvement and often requiring invasive intervention, have been documented previously. We report a patient with RV infarction and right-to-left shunt via PFO who improved with only early revascularization and optimal standard treatment. This condition may not necessitate any invasive intervention if it is treated and monitored per standard procedures. Clinicians should consider the possibility of a right-to-left shunt in patients with RV infarction and persistent hypoxemia to implement appropriate therapeutic interventions.