Silent Cerebral Infarcts in Patients With Pulmonary Embolism and a Patent Foramen Ovale

Abstract

Background and Purpose-Pulmonary embolism is thought to be associated with a small but definite risk of paradoxical embolism in patients with a patent foramen ovale (PFO). Although neurological complications are infrequent, the incidence of clinically silent brain infarction is unknown. We assessed the rate of clinically apparent and silent cerebral embolism in patients with pulmonary embolism in relation to the presence or not of a PFO. Methods-We used diffusion-weighted MRI in patients hospitalized for a pulmonary embolism to assess cerebral embolic events. Sixty consecutive patients were evaluated at diffusion-weighted MRI. All patients underwent neurological assessment before diffusion-weighted MRI and a contrast echocardiography to detect PFO the next day. Results-Diffusion-weighted MRI showed bright lesions in 6 patients among the 60 consecutive patients with pulmonary embolism in a pattern consistent with embolic events. There was only one patient with a neurological deficit. After contrast echocardiography, a PFO was diagnosed in 15 patients (25%).

Acute Pulmonary Embolism and Paradoxical Embolism in Patients with Patent Foramen Ovale: to Close or Not to Close…That is the Question!

“…A recent study, which considered PE patients classified as intermediate-risk, revealed a PFO prevalence of 17.7 % [8]. On the contrary, a lower percentage have been found from Clergeau et al in PE patients classified as low-risk PE [9]. Nowadays, despite seems that the prevalence of PFO increases with the severity of PE, due to the absence of definitive results, the real prevalence of PFO among the different PE risk groups remains matter of speculation.…”

Patent foramen ovale (PFO) and cryptogenic stroke

“…That PFO may enhance the risk of getting brain emboli has been further elegantly shown by a recent prospective study that identified, by logistic regression analysis, PFO was found to be an independent predictor of silent brain infarction with an OR of 34.9 (95% CI 31-394.3, P = 0.004) [7].…”

“…They came to the conclusion that PFO may represent an incidental finding in 33-48% of cryptogenic strokes when in isolation, but only in 11% when associated with bulging of the interatrial wall (so called atrial septal aneurism -ASA). These figures drop to 20% and 9%, respectively, in patients less than 55 years old [5].Similarly, a prospective study conducted in France on the risk of recurrence in young patients with cryptogenic stroke [6] showed that, compared with patents with no atrial septal abnormalities, the PFO-ASA association conveyed a 4-fold risk of relapse (hazard ratio 4.17, 95% CI 1.47-11.84).That PFO may enhance the risk of getting brain emboli has been further elegantly shown by a recent prospective study that identified, by logistic regression analysis, PFO was found to be an independent predictor of silent brain infarction with an OR of 34.9 (95% CI 31-394.3, P = 0.004) [7].The difficulty in identifying those with truly cryptogenic stroke amongst aged patients (due to the frequent cooccurrence of vascular risk factors) probably explains why PFO was only marginally associated with stroke in patients aged over 55 years in older studies [1]. Recent evidence, however, strongly suggests that PFO is over-represented in cryptogenic strokes irrespective of the age of occurrence [4].…”

Patent foramen ovale: to close or not to close – still the question

“…This is significantly more common than in patients without a PFO, which was reported at 2% (n = 1/45, p = 0.003) [9]. Numerous retrospective, casecontrol studies have also shown a higher prevalence of PFO in patients with cryptogenic stroke.…”