Lack of association between right-to-left shunt and cerebral ischemia after adjustment for gender and age

<p>Abstract</p> <p>Introduction</p> <p>A number of studies has addressed the possible association between patent foramen ovale (PFO) and stroke. However, the role of PFO in the pathogenesis of cerebral ischemia has remained controversial and most studies did not analyze patient subgroups stratified for gender, age and origin of stroke.</p> <p>Methods</p> <p>To address the role of PFO for the occurrence of cerebral ischemia, we investigated the prevalence of right-to-left shunt in a large group of patients with acute stroke or TIA. 763 consecutive patients admitted to our hospital with cerebral ischemia were analyzed. All patients were screened for the presence of PFO by contrast-enhanced transcranial Doppler sonography at rest and during Valsalva maneuver. Subgroup analyses were performed in patients stratified for gender, age and origin of stroke.</p> <p>Results</p> <p>A right-to-left shunt was detected in 140 (28%) male and in 114 (42%) female patients during Valsalva maneuver, and in 66 (13%) and 44 (16%) at rest respectively. Patients with right-to-left shunt were younger than those without (<it>P </it>< 0.001). PFO was associated with stroke of unknown origin in male (<it>P </it>= 0.001) but not female patients (<it>P </it>> 0.05). After adjusting for age no significant association between PFO and stroke of unknown origin was found in either group.</p> <p>Conclusion</p> <p>Our findings argue against paradoxical embolization as a major cause of cerebral ischemia in patients with right-to-left shunt. Our data demonstrate substantial gender-and age-related differences that should be taken into account in future studies.</p

Decrease in shunt volume in patients with cryptogenic stroke and patent foramen ovale

<p>Abstract</p> <p>Background</p> <p>In patients with patent foramen ovale (PFO) there is evidence supporting the hypothesis of a change in right-to-left shunt (RLS) over time. Proven, this could have implications for the care of patients with PFO and a history of stroke. The following study addressed this hypothesis in a cohort of patients with stroke and PFO.</p> <p>Methods</p> <p>The RLS volume assessed during hospitalisation for stroke (index event/T0) was compared with the RLS volume on follow-up (T1) (median time between T0 and T1 was 10 months). In 102 patients with a history of stroke and PFO the RLS volume was re-assessed on follow-up using contrast-enhanced transcranial Doppler/duplex (ce-TCD) ultrasound. A change in RLS volume was defined as a difference of ≥20 microembolic signals (MES) or no evidence of RLS during ce-TCD ultrasound on follow-up.</p> <p>Results</p> <p>There was evidence of a marked reduction in RLS volume in 31/102 patients; in 14/31 patients a PFO was no longer detectable. An index event classified as cryptogenic stroke (P < 0.001; OD = 39.2, 95% confidence interval 6.0 to 258.2) and the time interval to the follow-up visit (P = 0.03) were independently associated with a change in RLS volume over time.</p> <p>Conclusions</p> <p>RLS volume across a PFO decreases over time, especially in patients with cryptogenic stroke. These may determine the development of new strategies for the management in the secondary stroke prevention.</p

Investigation of Association between PFO Complicated by Cryptogenic Stroke and a Common Variant of the Cardiac Transcription Factor GATA4

Patent foramen ovale (PFO) is associated with clinical conditions including cryptogenic stroke, migraine and varicose veins. Data from studies in humans and mouse suggest that PFO and the secundum form of atrial septal defect (ASDII) exist in an anatomical continuum of septal dysmorphogenesis with a common genetic basis. Mutations in multiple members of the evolutionarily conserved cardiac transcription factor network, including GATA4, cause or predispose to ASDII and PFO. Here, we assessed whether the most prevalent variant of the GATA4 gene, S377G, was significantly associated with PFO or ASD. Our analysis of world indigenous populations showed that GATA4 S377G was largely Caucasian-specific, and so subjects were restricted to those of Caucasian descent. To select for patients with larger PFO, we limited our analysis to those with cryptogenic stroke in which PFO was a subsequent finding. In an initial study of Australian subjects, we observed a weak association between GATA4 S377G and PFO/Stroke relative to Caucasian controls in whom ASD and PFO had been excluded (OR = 2.16; p = 0.02). However, in a follow up study of German Caucasians no association was found with either PFO or ASD. Analysis of combined Australian and German data confirmed the lack of a significant association. Thus, the common GATA4 variant S377G is likely to be relatively benign in terms of its participation in CHD and PFO/Stroke

Patent foramen ovale in a cohort of young patients with cryptogenic ischemic stroke Forame oval patente em uma coorte de pacientes jovens com acidente vascular cerebral isquêmico

OBJECTIVE: Although its role is a matter of debate, some studies described a higher prevalence of patent foramen ovale (PFO) and atrial septal aneurysm (ASA) in young stroke patients, with higher risk with PFO / ASA association (OR 4.96). The aim of this study was determine the prevalence of PFO and ASA in a cohort of cryptogenic ischemic stroke (IS) patients younger than 55 years and to follow-up after surgical or percutaneous endovascular closure (PEC). METHOD: In 21 months we identified all patients less than 55 years old with IS who were admitted to our hospital. Cryptogenic IS was considered if there is not an identifiably cause to cerebral ischemia. Transesophageal echocardiography (TEE) was performed in all patients. After interatrial septal abnormalities diagnosis, percutaneous device closure was offered to all. Patients were followed monthly and keeped with oral AAS or Clopidogrel. RESULTS: We identified 189 patients with IS and 32 were less than 55 years old (16.9%). In 29 the IS was cryptogenic. TEE was performed in all patients and some form of interatrial septal abnormality was identified in 12 (12/29 - 41.3%); 5 had a PFO and in 7 there was PFO plus ASA. Ten patients were submitted to PEC and 2 were submitted to surgical closure. In mid-term follow-up (28 months) no ischemic events occurred and 2 patients related disappearance of migraine symptoms. CONCLUSION: Our small series description is in accordance with other studies and suggests a possible relation between interatrial septal abnormalities and IS in a cohort of young patient.<br>OBJETIVO: A associação das anormalidades do septo interatrial - forame oval patente (FOP) e aneurisma de septo interatrial (ASA) - com acidente vascular cerebral isquêmico (AVCI) ainda é questão de incerteza para muitos autores. No entanto, vários estudo mostram que em pacientes jovens tais anormalidades podem estar relacionadas à gênese de eventos isquêmicos. Nosso objetivo é descrever a prevalência do FOP e ASA em uma coorte de pacientes jovens (< 55 anos) com AVCI e acompanhar estes pacientes após fechamento cirúrgico ou por prótese endovascular. MÉTODO: Em 21 meses de estudo, identificamos todos os pacientes com menos de 55 anos de idade admitidos em nosso hospital por AVCI. Consideramos AVCI como criptogenético quando não havia uma causa provável para AVCI. Todos os pacientes foram submetidos ao ecocardiograma transesofágico. O fechamento por prótese endovascular foi o procedimento oferecido àqueles com alguma anormalidade do septo interatrial. Os pacientes foram acompanhados mensalmente e submetidos a antiagregação plaquetária com AAS ou clopidogrel. RESULTADOS: Foram admitidos 32 pacientes jovens com AVCI. Após ampla investigação, 29 receberam o diagnóstico de AVCI criptogênico. Destes, 12 (12/29 - 41,3%) apresentaram alguma anormalidade do septo interatrial; sendo que em 7 havia a associação de FOP e ASA. Dez pacientes foram submetidos a fechamento endovascular percutâneo e 2 foram submetidos a fechamento cirúrgico. Até o momento, nenhum paciente relatou recorrência do evento isquêmico e 2 pacientes relataram melhora das crises de enxaqueca (14 meses de seguimento). CONCLUSÃO: Nossa pequena série de casos está de acordo com outros estudos e sugere uma possível relação entre anormalidades do septo interatrial e AVCI em pacientes jovens. Maiores estudos são necessários para comprovar esta associação e para definir a melhor conduta terapêutica