[Ischemic stroke due to paradoxical embolism through pulmonary arteriovenous malformation in a young patient]. / ACV isquémico debido a embolia paradojal a través de malformación arteriovenosa pulmonar en paciente joven.

Paradoxical embolism due to an isolated pulmonary arteriovenous malformation (PAVM) is a rare cause of ischemic stroke. PAVMs are abnormal high-flow connections between pulmonary arteries and veins, diverting deoxygenated blood into the systemic circulation and they represent a less common source of paradoxical embolisms, especially in young individuals. Endovascular embolization is the preferred treatment for clinically significant PAVMs. We present the case of a 34-year-old woman with a left thalamic ischemic stroke. Severe contrast passage was detected in cerebral arteries through transcranial Doppler. Intracardiac ultrasound did not reveal a patent foramen ovale, prompting further investigation with pulmonary CT angiography, confirming the presence of PAVM. The patient underwent successful endovascular treatment. It is essential to consider PAVM in the etiological diagnosis of ischemic stroke, especially in young patients with signs of abnormal right-to-left communication. Periodic follow-up imaging is recommended to assess potential recurrence or changes in PAVM, emphasizing the importance of appropriate management of these malformations.

La embolia paradojal debido a una malformación arteriovenosa pulmonar (MAVP) aislada es una causa infrecuente de accidente cerebrovascular (ACV) isquémico. Las MAVP son conductos anómalos de alta circulación entre arterias y venas pulmonares, desviando sangre desoxigenada hacia la circulación sistémica y representan una fuente menos común de embolias paradojales, especialmente en personas jóvenes. La embolización endovascular es el tratamiento preferido para MAVP clínicamente significativas. Presentamos el caso de una mujer de 34 años con ACV isquémico talámico izquierdo. Se detectó pasaje de burbujas "en cortina" en arterias cerebrales mediante Doppler transcraneal. En ecografía intracardíaca no se encontró foramen oval permeable, motivo por el cual se avanzó con realización de angiotomografía pulmonar, la cual confirmó la presencia de MAVP. La paciente recibió tratamiento endovascular exitoso. Es esencial considerar la MAVP en el diagnóstico etiológico del ACV isquémico, especialmente en pacientes jóvenes con signos de comunicación anormal de derecha a izquierda. Se recomienda un seguimiento periódico mediante imágenes para evaluar la posible recurrencia o cambios en la MAVP, resaltando la importancia del manejo adecuado de estas malformaciones.

[Management of patent foramen ovale in non-cardiac surgery]. / Gestione della pervietà del forame ovale nella chirurgia non cardiaca.

Patent foramen ovale (PFO) is a remnant of normal fetal anatomy which may persist into adulthood, mostly asymptomatic. In some adults, PFO may result in a potential for shunting venous thromboembolism to the arterial circulation; less frequently it can cause interatrial, right-to-left shunting of deoxygenated blood. The pathogenesis of several medical conditions is related to the presence of PFO. Some randomized clinical trials have shown evidence of benefit for device closure as compared with medical therapy in patients with cryptogenic stroke. The literature reported several cases of carbon dioxide embolism during general laparoscopic surgery and sometimes stroke after laparoscopic or neurosurgery but there are neither prospective studies addressing these issues, nor randomized clinical trials assessing the effectiveness of pharmacotherapy or interventional procedures at decreasing risk. The European position paper suggests routine monitoring in non-cardiac surgery of patients with a PFO and no actual indications for closure. This article aims to further stratify the risk of periprocedural stroke and paradoxical embolism in this category of patients.

Paradoxical Embolic Stroke Following Percutaneous Transluminal Angioplasty in a Hemodialysis Patient.

Paradoxical embolism is a medical condition characterized by the migration of an embolus from a venous source into the systemic circulation. This occurs through a specific cardiac abnormality known as a right-to-left shunt, ultimately resulting in the possibility of arterial embolism. Patent foramen ovale (PFO) is the most common cause of intracardiac shunting. We reported a rare case of a 56-year-old man on hemodialysis with PFO and arteriovenous fistula dysfunction who suffered a paradoxical embolic ischemic stroke after percutaneous transluminal angioplasty. This case emphasized the potential risk of paradoxical embolism in hemodialysis patients with vascular access problems. We aimed to highlight the importance of searching for PFO, as it may serve as a possible source of embolism in these patients.

Comparison of atrial septal defect and patent foramen ovale in cryptogenic strokes.

OBJECTIVES: Paradoxical embolism from right-to-left shunt through atrial septal defect (ASD) and patent foramen ovale (PFO) is a well-accepted cause of "cryptogenic" strokes (CS). To better understand the pathogenic role of ASD, we compared ASD patients with CS having a high and low likelihood of being PFO-related. METHODS: In the Acute Stroke Registry and Analysis of Lausanne, we calculated prevalence of PFO and ASD in CS patients undergoing echocardiography, and calculated odds ratios (OR) when compared to non-CS. Using the Risk of Paradoxical Embolism (RoPE) score, we divided CS PFO patients in high (HL-PFO, RoPE 8-10) and low-likelihood (LL-PFO, RoPE 0-4) PFO-related stroke. We then performed univariate comparison of epidemiological, clinical and radiological variables of ASD patients with both PFO groups. RESULTS: Among all CS, prevalence of ASD and PFO were 1.3% and 36.8% respectively. When compared to non-CS, ASD and PFO were associated with CS (OR of 5.2, CI= 1.6-16.6, and 2.8, CI= 2.1-3.8). Compared with HL-PFO, ASD patients were older, more often female, had more cardiovascular risk factors and silent strokes. Compared with LL-PFO, ASD patients were younger, more often female, and had less risk factors. No differences were found for clinical and radiological characteristics and clinical outcome. CONCLUSION: ASD is a rare stroke risk factor for CS. Since characteristics of such patients lie in-between high and low-likelihood paradoxical PFO-strokes, a thorough work-up for other stroke mechanisms is warranted. Individual evaluation of the likelihood of the ASD being causative for stroke may be preferable over routine ASD closure.

Kidney Transplant Recipient With Cerebral Paradoxical Embolism Following Recurrent Idiopathic Deep Vein Thrombosis and Pulmonary Embolism: Case Report and Review of the Literature.

Paradoxical embolism occurs when a thrombus crosses an intracardiac defect into the systemic circulation. Here, we present the case of a 35-yearold male kidney transplant recipient with a cerebral paradoxical embolism associated with a spontaneous venous thromboembolism. This patient had recurrent deep venous thrombosis and showering emboli to the lung and paradoxically to the brain through patent foramen ovale, and we treated him successfully. The role of bubble echocardiography was essential in diagnosis to avoid contrast-induced nephropathy. This is the first successfully managed case of a kidney transplant recipient with recurrent idiopathic deep vein thrombosis, pulmonary embolism, and cerebral paradoxical embolism. Bubble echocardiography was an excellent alternative to contrast angiography to avoid nephrotoxicity. Vitamin K antagonists are superior to direct oral anticoagulants, especially among nonadherent/noncompliant patients.

Risk factors for the development of cryptogenic stroke and the predictive value of right-to-left shunt in patent foramen ovale.

OBJECTIVE: The purpose of this study was to evaluate the relationship between the right-to-left shunt of the patent foramen ovale and the risk score for paradoxical embolism in cryptogenic stroke, as well as the risk factors for the development of cryptogenic stroke. PATIENTS AND METHODS: A retrospective analysis was performed on 257 patients with cryptogenic stroke who were diagnosed and treated in our hospital from February 2020 to January 2022 as a study group, and 98 patients who were diagnosed and treated at the Department of Neurology in our hospital at the same time and excluded from stroke, were selected as the control group. Transcranial Doppler ultrasound acoustic contrast testing was used to grade right-to-left shunts of patent foramen ovale. Clinical information of individuals who had cryptogenic strokes was examined. The correlation between the right-to-left shunt of patent foramen ovale and the risk score for both cryptogenic stroke and paradoxical embolism was analyzed. The factors affecting the occurrence of cryptogenic stroke were investigated. The correlation between right-to-left shunt and paradoxical embolism risk score was explored. Receiver operator characteristic curve (ROC) analysis was used to evaluate each factor's clinical usefulness in predicting the occurrence of cryptogenic stroke. RESULTS: No difference was observed in the history of hypertension, low-density lipoprotein, C-reactive protein and fibrinogen between the control group and the study group (p<0.05). In the study group with patent foramen ovale, the proportion of patients with grades I and II of the right-to-left shunt of patent foramen ovale was significantly lower than that in the control group, while the percentage of patients with grades III and IV was obviously greater than that in the control group (p<0.05). Right-to-left shunt grade, C-reactive protein, and fibrinogen were independent risk factors for cryptogenic stroke by logistic multivariate regression analysis (p<0.05). With an increase in the right-to-left shunt of the patent foramen ovale, patients' risk scores for paradoxical embolism increased considerably (p<0.05). In patients with cryptogenic stroke, the right-to-left shunt grade of the patent foramen ovale was positively connected with the paradoxical embolism risk score (r=0.331, p<0.001). ROC analysis results showed that the areas under the curves (AUC) of right-to-left shunt grading, C-reactive protein, and fibrinogen were 0.651, 0.871, and 0.779, respectively. The combination of the three indexes had an AUC of 0.908, a sensitivity of 87.90%, a specificity of 82.70%, and a Youden index of 0.706, indicating a high predictive value of the combination. CONCLUSIONS: The right-to-left shunt of patent foramen ovale was an independent risk factor for cryptogenic stroke, which was positively correlated with the paradoxical embolic risk score. Its combination with clinical serologic indexes had a high clinical value for predicting cryptogenic stroke.

[Uncommon cause of acute coronary syndrome : Paradoxical embolism]. / Une cause rare de syndrome coronarien aigu : l'embolie paradoxale.

Coronary artery embolism is an uncommon cause of myocardial infarction (MI). Among several etiologies of coronary embolism, we mention a very rare cause which is the paradoxical embolism via patent foramen ovale (PFO). It interests generally youngest people without cardiac risk factors. We report three cases who presented ST-elevation MI (STEMI) due to paradoxical embolism with high risk PFO that can justify embolic infarction. The aim of this article is to define the high risk PFO, to establish causal link between PFO and embolic events and to guide therapeutic management.

Predictors of recurrent cerebral ischemia after patent foramen ovale closure: A single center observational study.

OBJECTIVES: Transcatheter patent foramen ovale closure lowers recurrent stroke in patients with cryptogenic stroke or transient ischemic attack with an indication for closure. However, the incidence of recurrent stroke is not negligible and underlying pathophysiology remains largely unknown. We sought to evaluate the prevalence of recurrent ischemic neurological events and to assess its predictors after transcatheter patent foramen ovale closure. METHODS: We enrolled consecutive patients who underwent patent foramen ovale closure for secondary prevention of neurological ischemic events at the University Hospital of Parma between 2006 and 2021. Clinical and procedure-related features were collected for each patient. The incidence of recurrent ischemic neurological events was assessed at follow-up. RESULTS: We enrolled a total of 169 patients with mean Risk of Paradoxical Embolism score at hospital admission of 6.4 ± 1.5. The primary indication was previous cryptogenic stroke (94 [55.6 %] subjects), followed by transient ischemic attack (75 [44.4 %]). Among patients with complete outcome data (n= 154), after a median follow-up of 112 months, recurrent cerebral ischemia occurred in 13 [8.4 %], with an annualized rate of 0.92/100 patients. The presence of obesity [OR 5.268, p = 0.018], Risk of Paradoxical Embolism score < 7 [OR 5.991, p = 0.035] and migraine [OR = 5.932 p = 0.012] were independent positive predictors of recurrent stroke/ transient ischemic attack after patent foramen ovale closure. CONCLUSIONS: The presence of obesity, Risk of Paradoxical Embolism score < 7 and migraine were independent positive predictors of recurrent ischemic neurological events after patent foramen ovale closure.

Retinal arterial occlusion and patent foramen ovale: A case study-based review.

PURPOSE: To identify all reported cases of retinal artery occlusion (RAO) associated with patent foramen ovale (PFO) in the literature and present a similar case of CRAO from our clinic. METHODS: PubMed database was searched for studies reporting RAO in individuals with PFO. Relevant data were tabulated and reviewed. We estimated each case's Risk of Paradoxical Embolism (RoPE) score. RESULTS: 23 cases of CRAO (n=10; including ours), BRAO (n=10), and CILRAO (n=3) were reviewed. Most cases were under 50 years of age (78.3%). The reported predisposing factors were: hypertension (26.1%), migraine (17.3%), smoking (13.0%), recent immobilization (13.0%), strenuous exertion (8.7%), pregnancy (8.7%), and diabetes (4.3%). A high RoPE score (≥7; suggestive of paradoxical embolism via PFO) was estimated for 71.4% of patients. In most cases, the neurological and cardiovascular examinations, laboratory studies, and imaging were unremarkable, except for the PFO±atrial septal aneurysm (present in 21.7%). In only 28.6% of cases, transthoracic echocardiography (TTE) (± saline contrast) could visualize the PFO; transesophageal echocardiography (TEE) was necessary to detect the PFO in 71.4%. Approximately one-half of the patients underwent percutaneous closure of the PFO; no complications or subsequent acute ischemic events ensued. The visual prognosis was poorer for CRAO than for BRAO or CILRAO. CONCLUSION: Timely diagnosis, acute management, and ensuring urgent initiation of stroke workup in cases with RAO or transient monocular vision loss are crucial. Clues to a possible paradoxical embolism as the cause include the absence of known cardiovascular risk factors, young age, migraine, recent immobility, vigorous exercise, and pregnancy.

Propensity-score matched analysis of patent foramen ovale closure in real-world study cohort with cryptogenic ischemic stroke.

INTRODUCTION: Patent foramen ovale (PFO) occurs in 25% of the general population and in 40% of cryptogenic ischemic stroke patients. Recent trials support PFO closure in selected patients with cryptogenic stroke. We examined the outcomes of transcatheter PFO closure in a real-world study cohort with cryptogenic stroke. METHODS: Consecutive ischemic stroke patients who were classified as cryptogenic on the TOAST aetiology and diagnosed with a PFO were included. All patients underwent either transcatheter PFO closure or medical therapy. A 2:1 propensity score matching by sex and Risk-of-Paradoxical-Embolism (RoPE) score was performed. Multivariable regression models adjusted for sex and RoPE score. RESULTS: Our cohort comprised 232 patients with mean age 44.3 years (SD 10.8) and median follow-up 1486.5 days. 33.2% were female. PFO closure (n=84) and medical therapy (n=148) groups were well-matched with <10% mean-difference in sex and RoPE score. Two patients in the treated group (2.4%) and seven in the control group (4.7%) had a recurrent ischemic stroke event. Multivariable Cox regression demonstrated a hazard-ratio of 0.26 (95%CI 0.03-2.13, P=0.21) for PFO closure compared to control. The incidence of atrial fibrillation (AF) detected post-PFO closure was similar between the treated and control (1.19% vs 1.35%, multivariable logistic regression odds-ratio 0.90, 95%CI 0.04-9.81, P=0.94). There were no major periprocedural complications documented. The difference in restricted mean survival-time free from stroke at two years between treated and control was 26.2 days (95%CI 5.52-46.85, P=0.013). CONCLUSIONS: In this Asian cohort, we report a low incidence of ischemic stroke recurrence and new-onset AF in patients who underwent PFO closure. When compared to the medical therapy group, there was no significant difference in the incidence of stroke recurrence and new-onset AF. Further studies involving larger real-world cohorts are warranted to identify patients who are more likely to benefit from PFO closure.

Sex Differences in Patients With Cryptogenic Cerebrovascular Events Undergoing Transcatheter Closure of Patent Foramen Ovale.

Background Scarce data exist on sex differences in patients with cryptogenic cerebrovascular events undergoing patent foramen ovale (PFO) closure. This study aimed to determine the sex differences in clinical profile, procedural characteristics, and long-term outcomes of patients with cryptogenic cerebrovascular events undergoing PFO closure. Methods and Results A retrospective cohort was used, including 1076 consecutive patients undergoing PFO closure because of a cryptogenic cerebrovascular event. Patients were divided into 2 groups: 469 (43.6%) women and 607 (56.4%) men. The median follow-up was 3 years (interquartile range, 2-8 years). Women were younger (46±13 versus 50±12 years; P<0.01) and had a higher risk of paradoxical embolism score (6.9±1.7 versus 6.6±1.6; P<0.01). Procedural characteristics and postprocedural antithrombotic therapy were similar. At follow-up, there were no differences in atrial fibrillation (women versus men: 0.47 versus 0.97 per 100 patient-years; incidence rate ratio [IRR], 0.55 [95% CI, 0.27-1.11]; P=0.095; adjusted P=0.901), stroke (0.17 versus 0.07 per 100 patient-years; IRR, 2.58 [95% CI, 0.47-14.1]; P=0.274; adjusted P=0.201), or transient ischemic attack (0.43 versus 0.18 per 100 patient-years; IRR, 2.58 [95% CI, 0.88-7.54]; P=0.084; adjusted P=0.121); nevertheless, women exhibited a higher incidence of combined ischemic cerebrovascular events (0.61 versus 0.26 per 100 patient-years; IRR, 2.58 [95% CI, 1.04-6.39]; P=0.041; adjusted P=0.028) and bleeding events (1.04 versus 0.45 per 100 patient-years; IRR, 2.82 [95% CI, 1.41-5.65]; P=0.003; adjusted P=0.004). Conclusions Compared with men, women with cryptogenic cerebrovascular events undergoing PFO closure were younger and had a higher risk of paradoxical embolism score. After a median follow-up of 3 years, there were no differences in stroke events, but women exhibited a higher rate of combined (stroke and transient ischemic attack) cerebrovascular events and bleeding complications. Additional studies are warranted to clarify sex-related outcomes after PFO closure further.

Transcatheter Patent Foramen Ovale Closure in Patients With Transient Ischemic Attack.

Limited data exist on patients with a transient ischemic attack (TIA) who underwent patent foramen ovale (PFO) closure. The objectives of this study were to determine the clinical and procedural characteristics and long-term outcomes of patients with TIA who underwent transcatheter PFO closure. This was a multicenter study including 1,012 consecutive patients who underwent PFO closure after a cerebrovascular event. Patients were divided into 2 groups according to their index event leading to PFO closure: TIA (n = 183 [18%]), and stroke (n = 829 [82%]). The median follow-up was 3 (2 to 8) years (complete in 98% of patients). There were no significant differences between patients with TIA and stroke, except for a lower Risk of Paradoxical Embolism score in the TIA group (6.1 vs 6.9 in the stroke group, p <0.001). PFO closure was successful in all patients with a low rate of complications (<1%) in both groups. There were no differences in the incidence of neurologic events during long-term follow-up. There was 1 stroke event in the TIA group and 6 in the stroke group (0.08 vs 0.17 per 100 patients-years, p = 0.584). There were 2 TIA events in the TIA group and 10 in the stroke group (0.17 vs 0.28 per 100 patients-years, p = 0.557). In conclusion, our study showed that patients with TIA who underwent PFO closure have similar clinical characteristics as patients with stroke including a high Risk of Paradoxical Embolism score. Furthermore, these results suggest that PFO closure procedural results and long-term clinical outcomes are similar to their stroke counterparts, with a very low incidence of recurrent neurologic events. Further prospective randomized clinical trials are needed on this population.

Potential Embolic Sources in Embolic Stroke of Undetermined Source Patients with Patent Foramen Ovale.

INTRODUCTION: A patent foramen ovale (PFO) may coexist with other potential embolic sources (PESs) in patients with embolic stroke of undetermined source (ESUS), leading to difficulty in attributing the stroke to either the PFO or other PESs. We aimed to investigate the prevalence and predictors of concomitant PESs in ESUS patients with PFOs. METHODS: A retrospective cohort study was conducted in a tertiary stroke centre. Consecutive patients with ESUS and a concomitant PFO admitted between 2012 and 2021 were included in the study. Baseline characteristics and investigations as a part of stroke workup including echocardiographic and neuroimaging data were collected. PESs were adjudicated by 2 independent neurologists after reviewing the relevant workup. RESULTS: Out of 1,487 ESUS patients, a total of 309 patients who had a concomitant PFO with mean age of 48.8 ± 13.2 years were identified during the study period. The median Risk of Paradoxical Embolism (RoPE) score for the study cohort was 6 (IQR 5-7.5). Of the 309 patients, 154 (49.8%) only had PFO, 105 (34.0%) patients had 1 other PES, 34 (11.0%) had 2 PES, and 16 (5.2%) had 3 or more PES. The most common PESs were atrial cardiopathy (23.9%), left ventricular dysfunction (22.0%), and cardiac valve disease (12.9%). The presence of additional PESs was associated with age ≥60 years (p < 0.001), RoPE score ≤6 (p ≤0.001), and the presence of comorbidities including diabetes mellitus (p = 0.004), hypertension (p≤ 0.001), and ischaemic heart disease (p = 0.011). CONCLUSION: A large proportion of ESUS patients with PFOs had concomitant PESs. The presence of concomitant PESs was associated with older age and a lower RoPE score. Further, large cohort studies are warranted to investigate the significance of the PES and their overlap with PFOs in ESUS.

Transcatheter Closure of Patent Foramen Ovale in Patients With Peripheral (Noncerebrovascular) Embolism.

OBJECTIVES: Scarce data exist on noncerebrovascular peripheral embolism (NCPE) patients undergoing transcatheter patent foramen ovale (PFO) closure. The objectives of this study were to determine the clinical and procedural characteristics, and long-term outcomes of patients with NCPE undergoing transcatheter PFO closure. METHODS: This was a multicenter study including 1136 consecutive patients who underwent PFO closure after a thromboembolic event. Patients were divided into 2 groups according to the type of event leading to PFO closure, ie, cerebrovascular event (CVE, n = 1099 [96.7%]) and NCPE (n = 37 [3.3%]). The median follow-up was 3 years (interquartile range, 1-8), with follow-up complete in 98%. RESULTS: Patients in the NCPE group exhibited higher rates of prior or concomitant pulmonary embolism (29.7% vs 3.4%; P<.001), and prior myocardial infarction (24.3% vs 1.8%; P<.001). Most NCPE events were located in the limbs (41%), followed by coronary (27%) and renal/splenic/mesenteric arteries (12%). PFO closure was successful in all patients, with a low complication rate (<1%) in both groups. NCPE patients were more frequently treated with anticoagulation following PFO closure (63% vs 13%; P<.001). There were no differences between NCPE and CVE groups in death (0 per 100 patient years vs 0.4 per 100 patient-years; P=.53) or cerebrovascular events (1.3 per 100 patient-years vs 0.4 per 100 patient-years; P=.15) at follow-up. CONCLUSIONS: Patients with NCPE events undergoing PFO closure exhibited differential baseline characteristics compared with patients with CVEs; limbs and coronary arteries were the most frequent NCPE location. PFO closure results and long-term outcomes were similar to their CVE counterparts, with a very low rate of recurrent thromboembolic events. Further studies are needed in this population.