Patent Foramen Ovale and the Risk of Cerebral Infarcts in Acute Pulmonary Embolism-A Prospective Observational Study.

BACKGROUND: Pulmonary embolism (PE) is associated with a risk of consecutive paradoxical embolism with brain infarction through a patent foramen ovale (PFO). The aims of this study were to assess the rate of new ischemic brain lesions (IBLs) using magnetic resonance imaging (MRI) during a 12-month follow-up period with anticoagulation and to evaluate the potential relationship with the presence of PFO on transesophageal echocardiography (TEE).

SUBJECTS AND METHODS: Seventy-eight patients with acute PE underwent baseline contrast TEE with brain MRI. After the 12-month follow-up, 58 underwent brain MRI. The rates of MRI documenting new IBLs were measured based on the presence of PFO.

RESULTS: PFO was detected in 31 patients (39.7%). At baseline MRI, IBL was present in 39 of 78 patients (50%). The presence of IBL was not significantly higher in patients with PFO than in patients without PFO (20 [64.5% patients with PFO] versus 19 [40.4% without PFO] of 39 patients with baseline IBL, P = .063). At the follow-up MRI, in the group with new IBL (9 of 58 patients, 15.5%), the number of patients with PFO was significantly higher than that without PFO (7 [33.3%] versus 2 [5.4%], P = .008). PFO was identified as an independent predictor of new IBL (odds ratio 4.6 [1.6-47.4], P = .008).

CONCLUSIONS: The presence of PFO was associated with new IBL in patients with PE. These patients are at a higher risk of ischemic stroke despite effective anticoagulation therapy.