Background: Patent foramen ovale (PFO) is a vascular risk factor in young stroke patients.

Objective: [corrected] We sought to analyze the prevalence of thrombophilia in young stroke patients with patent foramen ovale (PFO).

Methods: Prospective study; a total of 130 consecutive young stroke patients (female: 58.5 %; mean age: 34; range: 15-45 years) consecutively admitted to the hospital during 2002-2003. All patients underwent a diagnostic protocol including echocardiogram, carotid echodoppler, transcranial doppler with bubble test, brain tomography scan or magnetic resonance imaging. Thrombophilia studies included fasting plasma levels of protein C, protein S, antithrombin III, lupus anticoagulant, anticardiolipin antibodies, lupus anticoagulant, antinuclear antibodies, and genetic testing for the factor V Leiden and C677T methylene tetrahydrofolate reductase mutations. Stroke subtype classification was done according to TOAST criteria.

Results: Etiology of stroke was: cryptogenic (67 %), cardioembolism (14.6 %), large artery atherosclerosis (8.5 %), small vessel occlusion (3.8 %) and other causes (5.4 %). 42 patients (32.3 %) had a PFO; 41 % of cryptogenic stroke patients had a PFO while 14.3 % of known cause stroke patients had a positive PFO (p = 0.003; OR: 4.15; IC 95%: 1.47-12.29). 23.8 % of positive PFO patients (10/42) had migraine, while 9.1 % negative PFO patients suffered migraine (OR: 3.13; CI 95 %: 1.02- 9.69; p=0.023). Prevalence of thrombophilia in positive and negative PFO patients, in young with cryptogenic stroke and stroke patients with known etiology, and in cryptogenic stroke patients with and without PFO was similar.

Conclusions: Thrombophilia does not seem to be an additional factor to the excess of risk observed in young patients with cryptogenic stroke and PFO.