Re: Clinical and imaging findings in cryptogenic stroke patients with and without patent foramen ovale.

Background and Purpose—Patent foramen ovale (PFO) has been identified as a potential risk factor for stroke, but the mechanisms of PFO-associated stroke remain unsettled. The aim of our study was to evaluate possible differences in stroke risk factors and stroke patterns between patients with and without PFO that may give clues to the mechanism of PFO-associated stroke. Methods—This prospective, multicentric study involved 581 young cryptogenic stroke patients. The presence of PFO and atrial septal aneurysm was assessed by transesophageal echocardiography and reviewed independently by 2 experienced sonographers. Clinical, brain, and vascular imaging findings were reviewed by 2 neurologists and 2 neuroradiologists. Results—Of the 581 stroke patients, 267 (45.9%) had PFO. Patients with PFO were younger (OR, 0.95; 95% CI, 0.93 to 0.97) and less likely to have traditional risk factors such as hypertension (OR, 0.49; 95% CI, 0.28 to 0.85), hypercholesterolemia (OR, 0.56; 95% CI, 0.34 to 0.93), or current smoking (OR, 0.67; 95% CI, 0.47 to 0.97). Features suggestive of paradoxical embolism, such as Valsalva-provoking activities or deep vein thrombosis, were not more frequent in patients with PFO. Migraine was more common in patients with PFO (27.3%) than in those without PFO (14.0%). PFO (OR, 1.75; 95% CI, 1.08 to 2.82), particularly when associated with atrial septal aneurysm (OR, 2.71; 95% CI, 1.36 to 5.41), was significantly associated with migraine after adjustment for age and sex . Conclusions—Differences in stroke risk factors and stroke patterns suggest that different stroke mechanisms occur in patients with and without PFO. PFO is significantly and independently associated with migraine, and this association is even stronger in patients with PFO and atrial septal aneurysm. (Stroke. 2002;33:706-711.)