Role of transoesophageal echocardiography in detecting patent foramen ovale in stroke patients aged ≤60 years: A retrospective study

BACKGROUND: The underlying aetiology of ischaemic strokes is unknown in as many as 50% of cases. Patent foramen ovale (PFO) has become an increasingly recognised cause of ischaemic strokes in young patients. The present study aimed (1) to assess the frequency of transoesophageal echocardiography (TOE) performed and the proportion of PFOs detected in patients aged ≤60 years and (2) examine the effect of PFO closure on reducing stroke reoccurrence. METHODS: This was a retrospective clinical audit based on de-identified, secure medical records of the Canberra Hospital, Australia. A review of records was conducted on discharged patients aged 18–60 years admitted to the stroke unit following an ischaemic stroke episode between January 1, 2015, and December 31, 2018. RESULTS: A total of 214 acute ischaemic stroke patients were admitted to the stroke unit (mean age, 49.2 ± 9.7 years). Concerning aetiology, 47.2% were cryptogenic in origin, whereas 52.8% had a stroke of a determined cause. 12 patients were diagnosed with a PFO and 7 venous thromboembolic events were identified, 1 in the cryptogenic group and 6 in the determined cause group. 91.7% of PFOs were diagnosed in patients with a cryptogenic stroke. Trans-thoracic echocardiography (TTE) was performed in 37.3% of patients and had detected 4 PFOs (sensitivity 27.3%, specificity 92.5%). TOE was performed in 26.2% of patients and had detected 11 PFOs (sensitivity 90.0%, specificity 100%). The number needed to treat to prevent the occurrence of an ischaemic stroke through PFO closure was estimated at 30. CONCLUSIONS: An inverse association between age and PFO presence was found in patients aged 18–60 years. Additionally, TOE was superior to TTE for detecting PFO, particularly in those with stroke of an undetermined cause. Our results suggest an increased need for TOE as a routine imaging procedure for acute ischaemic stroke patients aged ≤60.