Abstract for presentation at The Australian and New Zealand Association of Neurologists Annual Scientific Meeting 2007

Introduction: Migraine with aura has been shown to be more frequent in patients with right to left shunts such as atrial septal defect (ASD) and pulmonary arteriovenous fistula. Furthermore, migraine with aura is more prevalent in clinical entities associated with right to left shunts, such as cryptogenic stroke and decompression illness in divers. While studies of trans-oesophageal echocardiography in patients with cryptogenic embolic stroke have demonstrated a number of patients with ASD, a definite aetiological association between stroke and uncomplicated ASD has not been consistently demonstrated. The presence of an ASD with an atrial septal aneurysm and thrombophilia may incur an increased risk of stroke, but the optimal management of uncomplicated ASD in the setting of cryptogenic embolic stroke remains controversial.
Case Report: We wish to report 2 patients known to have a history of migraine with aura, who subsequently developed cryptogenic embolic stroke, and, who were also shown to have an ASD on echocardiography with right to left shunting. The focal neurological symptoms at the time of stroke were indistinguishable from their typical migraine aura. Both patients had uncomplicated closures of the ASD via intra-arterial catheter techniques. There has been no recurrence of migraine or stroke since ASD closure.
Conclusion: A high index of clinical suspicion is required to distinguish stroke and complicated migraine. While migrainous infarction cannot be excluded in these cases, the association of both migraine with aura and stroke with ASD in these patients is compelling, and raises questions regarding the aetiology of symptoms, as well as the optimal management of ASD in the setting of cryptogenic embolic stroke.