Pulmonary arteriovenous malformation and cryptogenic stroke / 国际脑血管病杂志

The relationship between pulmonary arteriovenous malformations (PAVMs) and stroke remains unclear. With the development of imaging technology, studies shows that PAVMs are an important cause of cryptogenic stroke (CS). Most PAVMs are not diagnosed until the onset of stroke. The main pathogenesis of PAVMs-related CS is paradoxical embolism and increased blood viscosity caused by iron deficiency anemia. Antiplatelet therapy and interventional therapy may have a preventive effect on recurrent stroke in such patients. This article summarizes the pathophysiological mechanism, diagnosis and treatment of PAVMs-related CS, hoping to provide new ideas for the diagnosis and treatment of CS.

Paradoxical brain embolism and pulmonary embolism due to a deep femoral venous aneurysm and patent foramen ovale: a case report / 中华神经科杂志

The cases of paradoxical brain embolism (PBE) due to venous aneurysms and patent foramen ovale (PFO) are extremely scarce, with only 5 cases caused by popliteal venous aneurysm reported in the literature to date, while PBE caused by deep femoral venous aneurysm (DFVA) and PFO has not been reported. Herein, an unusual case of PBE in a 15-year-old girl with PFO who still had cerebral infarction and pulmonary embolism after transcatheter closure was present. She was finally diagnosed as PFO with DFVA by angiography. Furthermore, clinical characteristics of 6 cases were summarized to improve the clinicians′ recognition of the rare risk factor of stroke-venous aneurysms of the lower extremity deep veins.

Comparison of right-to-left shunt characteristics in cryptogenic embolic ischemic stroke and non-cardioembolic ischemic stroke / Comparação das características do shunt direita-esquerda em pacientes com AVC isquêmico criptogênio e AVC não cardioembólico

Abstract Background: Patent foramen ovale (PFO) has been considered a potential mechanism of embolic stroke of undetermined origin. Objective: The aim of the present study was to identify the features of the right-to-left shunt (RLS) in patients with undetermined embolic ischemic stroke and compare them with those of patients with non-cardioembolic ischemic stroke. Methods: A retrospective study was conducted with 168 patients with stroke and RLS separated into the following two groups: the undetermined embolic stroke group (UES group) and non-cardioembolic stroke group (NCES group). All patients were assessed by transcranial Doppler to evaluate the presence and quantification of microembolic signals (MES) at rest and under Valsalva maneuver. Results: Of all patients evaluated in the current study, 96 were included in the UES group and 72 in the NCES group. In the UES group, 65 patients had RLS with ≥10 MES (67.7%), which was higher than that observed in the NCES group (51.4%, p=0.038). According to the moment of the cardiac cycle, 75 patients (78.1%) in the UES group had a positive test at rest compared to 42 (58.3%) in the NCES group (p=0.007). Conclusions: The current study demonstrated that almost 70% of patients with undetermined embolic stroke and PFO presented a large RLS and more than 75% had RLS at rest. These findings suggest that the size of the shunt should be taken into account when evaluating whether PFO could be a possible mechanism underlying cryptogenic stroke.

RESUMO Antecedentes: Uma das potenciais fontes embólicas no acidente vascular cerebral (AVC) de origem indeterminada é o forame oval patente (FOP). Objetivo: O objetivo do presente estudo foi identificar as características do shunt direita-esquerda em paciente com AVC de etiologia indeterminada, presumidamente embólica, e comparar tais características com pacientes apresentando AVC por outras causas não embólicas. Métodos: Trata-se de um estudo retrospectivo com 168 pacientes com AVC e forame oval patente, separados em dois grupos: AVC embólico de etiologia indeterminada e AVC por outras causas não embólicas. Todos os pacientes foram submetidos a Doppler transcraniano, para avaliar a presença de shunt direita-esquerda por meio do teste de embolia paradoxal. Além da quantificação de microbolhas, também foi avaliada a presença de shunt em repouso e sob manobra de Valsalva. Resultado: Do total, 96 pacientes foram incluídos no primeiro grupo (AVC indeterminado) e 72, no segundo grupo (AVC não embólico). No primeiro grupo, 65 pacientes exibiram shunt com passagem de mais de 10 microbolhas (67,5%), enquanto no segundo grupo isso aconteceu em 51,4% (p=0,038) dos casos. Além disso, 75 pacientes (78,1%) do primeiro grupo tiveram teste positivo ao repouso, comparados com 42 pacientes (58,3%) no segundo grupo (p=0,007). Conclusão: O presente estudo demonstrou que até 70% dos pacientes com AVC de etiologia indeterminada e forame oval apresentaram shunts maiores; em mais de 75%, houve passagem de microbolhas ao repouso. Esses achados sugerem que as características do shunt, como quantidade de microbolhas e passagem ao repouso, devem ser levadas em consideração na avaliação do FOP como possível mecanismo subjacente ao AVC.

Cryptogenic stroke in patients with patent foramen ovale: potential mechanisms and prevention strategies / 国际脑血管病杂志

Patent foramen ovale (PFO) is a congenital heart disease that occurs in about 25% of healthy adults. In recent years, more and more studies have shown that PFO is closely associated with cryptogenic stroke (CS). Although it is currently believed that paradoxical embolism is one of the main mechanisms of the pathogenesis of CS, but the exact mechanism is still controversial. In addition, the treatment of CS in patients with PFO is also the focus of controversy. Recent clinical trials have shown that PFO occlusion is significantly better than drug therapy alone in preventing stroke recurrence, especially for patients with a large right-to-left shunt and atrial septal tumor. This article reviews the potential mechanisms and prevention strategies of CS in patients with PFO.

Paradoxical cerebral embolism caused by pulmonary arteriovenous fistula: a case report / 中华神经科杂志

A young female patient with paradoxical cerebral embolism caused by pulmonary arteriovenous fistula,mainly presented the right limbs asthenia,and brain magnetic resonance imaging examination showed multiple acute cerebral infarctions in the left hemisphere,which belongs to left middle cerebral artery and left posterior cerebral artery blood areas.After excluding the common risk factors of cerebrovascular disease,foaming test suggested the right-to-left shunt.The esophageal ultrasound examination excluded the patent foramen ovala.The lung CT angiography examination confirmed the intracranial embolism caused by pulmonary arteriovenous fistula.There was no recurrence of ischemic stroke after the patient was treated with pulmonary arteriovenous fistula embolization.

Trombo a través de foramen oval permeable: embolia paradojal cerebral y factores de alto riesgo de recurrencia. Caso clínico / Paradoxical embolism due to a persistent patent foramen ovale: report of one case

Abstract: Patent Foramen Ovale (PFO) is one of the most frequent congenital defects in adults. Its prevalence in middle-aged adults is close to 25-30% and may cause paradoxical embolic phenomena. We report a 45 years old male admitted for an ischemic stroke with an occlusion of the left terminal internal carotid artery. A thrombectomy was performed. Searching for possible sources of emboli, a patent foramen ovale was detected in an echocardiography, with an hypoechogenic examination image passing through it. Anticoagulant therapy was started and the patient had an uneventful evolution.

Pulmonary embolism complicated with abnormal spinal cord embolism due to lack of protein S activity: a case report / 中华神经科杂志

Spinal vascular disease is rare in clinic, especially in cases of spinal cord embolism caused by abnormal embolism. It is rare in clinic and has not been reported in China. We report a case of pulmonary embolism complicated with abnormal spinal cord embolism due to lack of protein S activity and analyze its clinical data in order to improve clinical understanding of the disease.

Surgical treatment for thrombus straddling a patent foramen ovale

Abstract We present a case of a 41-year-old female with deep vein thrombosis after abdominal surgery. The patient quickly developed severe pulmonary embolism and stroke representative of paradoxical embolism. Echocardiography showed a thrombus straddling a patent foramen ovale, which was confirmed intraoperatively. An accurate diagnosis and rapid treatment decisions are crucial for preventing patient deterioration in the form of new pulmonary embolisms or stroke.

Cryptogenic stroke in patients w ith patent foramen ovale / 国际脑血管病杂志

Cryptogenic stroke refers to ischemic stroke that can not be defined by routine examination at present. Studies have show n that patent foramen ovale may be a common cause of cryptogenic stroke, and its possible mechanism is the paradoxical embolism. With the development of imaging technology , more and more studies have show n that patent foramen ovale is closely associated w ith cryptogenic stroke. This article review s cryptogenic stroke in patients w ith patent foramen ovale.

Diagnosis and treatment of pulmonary arteriovenous malformation with cryptogenic stroke caused by paradoxical embolism as the first manifestation / 中华神经科杂志

Objective To investigate the clinical and radiological features of the patients with cryptogenic stroke as the first manifestation of pulmonary arteriovenous malformation (PAVM),and to explore the mechanism and summarize the diagnostic strategy.Methods Transcmnial Doppler (TCD) bubble tests,non-contrast or contrast-enhanced transthoracic and transesophageal echocardiography,contrast-enhanced thoracic CT and pulmonary angiography were performed in 2 patients with cryptogenic stroke for the detection of right to left shunt (RLS) and the diagnosis of PAVM.Then interventional catheter embolization of PAVM and postoperative follow-up were arranged.Results TCD bubble tests in these 2 patients showed the following characteristics indicating RLS:spontaneous continuous shunt at rest,earlystage shunt appeared rapidly after injection,considerable large amount of shunt volume as a shower of microbubble,the extent of shunt volume not attenuated by Valsalva Maneuver (VM).One patient was diagnosed as PAVM,the other was PAVM plus patent foramen ovale (PFO).Both patients of PAVM were successfully treated with interventional catheter embolizations.Then TCD bubble test was repeated and showed significantly decreased amount of RLS.They remained asymptomatic during the 3-year and 1-year follow-up.Conclusions In patients with cryptogenic stroke due to suspected paradoxical embolism,TCD bubble test should be performed for screening RLS.Besides PFO,a traditional access to intracardiac shunt,PAVM should be considered as a new access to extracardiac shunt in paradoxical embolism.