Fatal asthma attributed to patent foramen ovale.

A 37 year old woman was admitted to the hospital with acute severe asthma, shortly followed by respiratory failure and circulatory arrest. Despite intensive cardio-pulmonary resuscitation, during which extreme arterial hypoxaemia persisted, the patient died. Postmortem examination revealed a patent foramen ovale, with a diameter of 1 cm. A severe right-to-left shunt, initiated by acute pulmonary hypertension, was considered to be the cause of death. Because of the relatively high prevalence of patent foramen ovale in the normal population, we suggest this patency may enhance the risk of fatal outcome of acute severe asthma.