RESUMO
OBJECTIVE: Patent foramen ovale (PFO) has been related to stroke but its existence has not been explained to date. NKX2-5 is the most implicated gene in fetal atrial septation. We studied NKX2-5 with respect to the presence or absence of PFO in stroke patients. METHODS: A prospective analysis of NKX2-5 regarding age, gender, PFO, right-to-left shunt (RLS) size and atrial septal aneurysm (ASA) was performed in consecutive stroke patients and in 50 controls. The entire coding region and intron-exon boundaries of NKX2-5 gene were analyzed by PCR and sequencing of DNA from peripheral lymphocytes. RESULTS: One hundred patients participated in the study (mean age 56.5+/-12.4 years, 58% males) and PFO was diagnosed in 34% of them by transesophageal echocardiography. RLS was small (12%), moderate (2%) and large (20%). ASA was present in four patients. DNA revealed a novel c.2357G>A change in one PFO patient with cryptogenic stroke. Furthermore, c.182C>T, a mutation previously described in patients with cardiac defects, was detected in two non-PFO women with cryptogenic stroke. None of these changes were detected in our controls. The c.172A>G polymorphism was found in 21% of controls. It appeared more frequently in ASA patients (p=0.084), in cryptogenic PFO stroke patients (p=0.097) and in patients with known causes of stroke (p=0.037). The c.2850C>A polymorphism was also detected in our series with no differences in PFO, RLS size or ASA. CONCLUSION: Despite the fact that the NKX2-5 could account for the persistence of PFO, mutations of this gene in peripheral blood DNA were barely detected in our study.
Assuntos
Forame Oval Patente/genética , Proteínas de Homeodomínio/genética , Mutação/fisiologia , Acidente Vascular Cerebral/genética , Fatores de Transcrição/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos , DNA/genética , Ecocardiografia Transesofagiana , Éxons/genética , Feminino , Forame Oval Patente/epidemiologia , Frequência do Gene , Proteína Homeobox Nkx-2.5 , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Espanha/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
Patent foramen ovale (PFO) is more frequent in cryptogenic stroke patients than in the general population. The aim of this study was to determine prothrombotic markers regarding PFO in young cryptogenic stroke patients. We prospectively included consecutive cryptogenic stroke patients younger than 55 years. PFO was diagnosed with simultaneous transcranial Doppler and transesophageal echocardiography. We analyzed the following prothrombotic markers: antiphospholipid antibodies (APS), protein C and protein S deficiencies, factor V Leiden FVG1691A, prothrombin gene mutation PTG20210A and coagulation factor XII mutation FXIIC46T. From June 2005 to July 2006 we studied 39 patients, mean age 44.7 +/- 8.6 years, 48.7% men. PFO was detected in 17 patients (43.6%). We found no differences between PFO and non-PFO patients regarding prothrombotic markers: APS (P = 0.851), protein S deficiency (P = 0.851), protein C deficiency (P = 0.249), FVG1691A (P = 0.202), PTG20210A (P = 0.401) or FXIIC46T (P = 0.966). Female gender was the only variable related to prothrombotic markers, independent of PFO (P = 0.001). The only prothrombotic marker related to PFO size (large PFO) was APS (P = 0.043). Large PFO were also related to deep venous thrombosis (P = 0.040) and atrial septal aneurysm (P = 0.010). PFO patients do not present more prothrombotic markers than non-PFO patients, but APS are more frequent in large PFO.
