The presence of an unknown intracardiac shunt due to a patent foramen ovale may be an unusual cause of hypoxemia. We report the case of a patient who presented persistent hypoxemia after an adequate treatment for a severe asthma attack requiring intensive care unit admission. The patient underwent a transthoracic microbubbles contrast echocardiography that showed a massive patent foramen ovale. The favorable clinical course and the absence of major signs and symptoms related to patent foramen ovale allowed a conservative approach with a follow-up program. Patent foramen ovale should be suspected in case of persistent hypoxemia after a severe asthma attack had resolved.
Keywords: Asthma attack; Echocardiography; Microbubbles contrast; Patent foramen ovale.