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.

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.

[Management of patent foramen ovale in non-cardiac surgery]

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.

[Uncommon cause of acute coronary syndrome : Paradoxical embolism]

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.

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.

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.

Paradoxical Embolism Is an Unusual Etiology of Acute Limb Ischemia in Patients Suffering from COVID-19 Infection

Acute limb ischemia (ALI) is a large contributor to morbidity and mortality annually and can be managed either operatively or medically. ALI is most often caused by arterial embolism or in situ thrombosis and treatment is often dependent upon the severity. Anticoagulation is considered standard of care and first line therapy. However, more severe cases of ALI require surgical intervention.Paradoxical emboli are a rare and potentially under-appreciated cause of ALI. They arise when venous emboli, from a variety of sources, traverse a patent foramen ovale (PFO) to enter the arterial system, compromising blood flow to the affected end organ. In most cases, they can only be proven if the thrombus is identified as it crosses the cardiac defect, at which point it is an indication for surgery requiring PFO closure, management for the ischemia itself, and possible intervention for the embolism.In this report, we identify and discuss management of a series of cases where ALI was precipitated by PFOs that were discovered in the context of a pulmonary emboli that developed into paradoxical emboli. All patients had a confirmed diagnosis of COVID-19 which has been associated with a state of hypercoagulability and subsequent thrombus formation.

[Ischemic stroke due to paradoxical embolism through pulmonary arteriovenous malformation in a young patient]

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.

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.

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.

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.

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&lt;.001), and prior myocardial infarction (24.3% vs 1.8%; P&lt;.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 (&lt;1%) in both groups. NCPE patients were more frequently treated with anticoagulation following PFO closure (63% vs 13%; P&lt;.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.

Prevalence of Patent Foramen Ovale in North Indian Cryptogenic Young Strokes

BACKGROUND

: Strokes of the undetermined cause or cryptogenic strokes (CS) account for 30-40% of ischemic strokes. Paradoxical embolism secondary to patent foramen ovale (PFO) may be associated with CS. Transcranial Doppler (TCD) with bubble contrast is a noninvasive bedside tool for diagnosis of right-to-left shunt (RLS) with high sensitivity and specificity. Data on the prevalence of PFO in CS in India are lacking. We determined the prevalence of RLS likely secondary to PFO in cryptogenic young strokes of the north Indian population using TCD with bubble contrast.

PATIENTS AND METHODS

: In this hospital-based prospective cross-sectional study, TCD with bubble contrast was performed in 57 young (age 15 > 45 years) CS and 50 healthy controls for the detection of RLS. The risk of paradoxical embolism (RoPE) score was calculated from various variables such as age, presence of cortical stroke on neuroimaging, and absence of vascular risk factors.

RESULTS

: 57 young CS and 50 healthy controls were recruited. TCD with bubble contrast was positive in 31% cases vs 6% in controls (P = 0.001). All patients with TCD positive for RLS had superficial cortical infarcts (P = 0.03). The median RoPE score of our patients was 9 (range: 7-10).

CONCLUSIONS

: There is a high prevalence of RLS likely secondary to PFO in cryptogenic young strokes in north India. TCD with bubble contrast is an excellent bedside tool for the detection of RLS.

Intracardiac versus extracardiac shunt in a young man with ischaemic stroke

A 24-year-old man with a history of recent ischaemic stroke was diagnosed with patent foramen ovale (PFO) and referred for closure at our hospital. At admission, besides low peripheral oxygen saturation (88%), physical examination was otherwise normal. We performed intraprocedural transoesophageal echocardiogram that revealed no PFO, although agitated saline injection demonstrated bubbles lately on the left atrium. The atrial septum could not be crossed. We suspected an extracardiac shunt, so pulmonary angiograms were performed that revealed the presence of a left pulmonary arteriovenous malformation (PAVM). A Konar-MF Occluder was used to occlude the PAVM, with a satisfactory result. At 6 months follow-up, the patient had normal peripheral oxygen saturation and a new pulmonary angiogram showed no residual shunt. Intrapulmonary shunts are a rare and under-recognised cause of paradoxical emboli in young patients; physicians should be aware of this diagnosis as percutaneous occlusion is indicated and critical to avoid recurrent ischaemic episodes.

Stroke Prevention in Patients with Patent Foramen Ovale

PURPOSE OF REVIEW

Patent foramen ovale (PFO) is widely prevalent and studies have suggested an association with ischemic stroke. In this review, we aim to highlight current management of patients with ischemic stroke in the setting of PFO and discuss some areas of controversy.

RECENT FINDINGS

Upon reviewing the literature, we have found that the evidence regarding the management of patients with cryptogenic stroke and PFO has come a long way in the past several years, and many uncertainties remain in clinical practice. The Risk of Paradoxical Embolism (RoPE) score helps to predict the probability of a pathogenic PFO, and recent trial data confirms the benefit of closure in carefully selected patients. The benefit of closure in older patients and in patients with alternate, competing mechanisms is still uncertain, and the long-term risks of closure are not known. Finally, the efficacy of direct oral anticoagulants (DOACs) in this patient population as compared to other medical therapy or mechanical closure has not yet been investigated. Randomized data is needed to help answer these questions. PFO closure is a safe and effective strategy in reducing stroke risk in carefully selected patients with cryptogenic stroke in the setting of a PFO. More studies are needed to test optimal medical treatment strategies and the safety and efficacy of PFO closure in patient subgroups not included in prior PFO closure trials.

Secondary stroke prevention in patients with patent foramen ovale

PURPOSE OF REVIEW

Although a patent foramen ovale (PFO) is an established risk factor for cryptogenic ischemic stroke, strategies for secondary prevention remain controversial. Increasing evidence over the past decade from well designed clinical trials supports transcatheter PFO closure for selected patients whose stroke was likely attributable to the PFO. However, patient selection using imaging findings, clinical scoring systems, and in some cases, thrombophilia testing, is crucial for determining patients most likely to benefit from closure, anticoagulation, or antiplatelet therapy.

RECENT FINDINGS

Recent studies have found that patients with a high Risk of Paradoxical Embolism (RoPE) score and those with a thrombophilia benefit more from closure than medical therapy (including antiplatelet or anticoagulant therapy) alone. Meta-analyses have demonstrated an increased short-term risk of atrial fibrillation in closure patients, and that residual shunt after closure predicts stroke recurrence. Last, recent data have been inconclusive as to whether patients receiving medical therapy only benefit more from anticoagulation or antiplatelet therapy, so this remains an area of controversy.

SUMMARY

Transcatheter PFO closure is an evidence-based, guideline-supported therapy for secondary stroke prevention in patients with a PFO and cryptogenic stroke. However, proper patient selection is critical to achieve benefit, and recent studies have helped clarify those patients most likely to benefit from closure.

[Impending Paradoxical Embolization in a Patient with a Thrombus Straddling the Patent Foramen Ovale]

The patent foramen ovale (PFO) is known as a risk of paradoxical embolism in patients with deep venous thromboses. However, PFO is usually found after systemic embolic symptoms become apparent. A 60-year-old male had complained of dyspnea for two weeks. Ultrasound echocardiography showed a thrombus straddling PFO, and venous echography showed blood clots in the right popliteal and soleus veins. Contrast computed tomography revealed multiple pulmonary embolisms and a thrombus in the right atrium expanding to the left atrium through the atrial septum. The straddling thrombus in the atrium and pulmonary thrombi were extirpated under circulatory arrest with deep hypothermia. An inferior vena cava filter was inserted intravenously four days after surgery. The patient was discharged on the 19th postoperative day without any signs of thromboembolism. Prompt surgery is considered important to prevent thromboembolism in the case of impending paradoxical embolism.

A Rare Presentation of Multi-Organ Embolism in a Multifactorial Hypercoagulable State: Case Report

Paradoxical embolism is an uncommon phenomenon, accounting for only 2% of all cases of systemic arterial embolism. This condition suggests the presence of a patent foramen ovale, present in 20% - 25% of the adult population. The authors report the case of a 63-year-old male patient with a history of lung adenocarcinoma and hereditary thrombophilia admitted to hospital with acute onset of dyspnea, diplopia, confusion and decreased motor strength of the right limbs. Cranial computed tomography scan showed acute ischemic injury in the left posterior cerebral artery and computed tomography pulmonary angiography revealed bilateral pulmonary thromboembolism. A transesophageal echocardiogram confirmed the presence of patent foramen ovale. The patient was treated with anticoagulant therapy with progressive clinical improvement. Due to a high risk of recurrent thromboembolic episodes, the percutaneous closure of patent foramen ovale was performed and anticoagulant therapy was maintained indefinitely.

Management of paradoxical embolism in a patient with coexisting patent foramen ovale and masked pulmonary arteriovenous fistula: A case report

RATIONALE

Paradoxical embolism (PE) is an important cause of cryptogenic stroke, particularly in young patients, which usually have a relation with an unexpected route in circulation. Here we report a rare case of cryptogenic stroke carried 2 uncommon malformations.

PATIENT CONCERNS

A 48-year-old female experienced double neurological events in just 2 months.

DIAGNOSIS

Patent foramen ovale was diagnosed with transesophageal echocardiography and successfully occluded in the first admission due to stroke. In the second admission, chest tomographic angiography found a chordae shadow in the right middle lobe, was the first clue for pulmonary arteriovenous fistula (PAVF), thereafter further confirmed by the enhanced pulmonary computed tomographic angiography.

INTERVENTIONS

This patient then received intervention occlusion therapy with coils for PAVF under the help of microcatheter. Given the possible native origin of the thrombus in PAVF due to the spiral morphology, dual antiplatelet therapy was prescribed for this patient for the first 3 months to prevent device-related embolism after discharge, and the following single antiplatelet therapy was mandated.

OUTCOMES

No recanalization was detected on the follow-up enhanced pulmonary computed tomographic angiography (PCTA), no neurological defect event recurred in the 16 months of follow-up.

LESSONS

Computed tomograph (CT) deserved more value in screening and depicting the morphology of the PAVF, particular in young adults with no apparent arteriosclerotic risk factor. Microcatheter would be helpful for intervention treatment. Antiplatelet therapy might be adequate in specific patients, yet definitely need more evidence to verify.

Diagnostic Yield of Early Examination for Venous Thrombosis in Patients with Cryptogenic Stroke and a Right-to-left Shunt

Objective The presence of deep venous thrombosis (DVT) in a cryptogenic stroke (CS) patient with a right-to-left shunt (RLS) may lead to the development of paradoxical embolism. The aim of the present was to investigate the prevalence of DVT and pulmonary embolism (PE) in CS patients and the clinical features of CS in relation to DVT location and the presence of PE. Methods The medical records of 903 patients with cerebral infarction were retrospectively reviewed. For patients with a diagnosis of CS, contrast saline transcranial color-coded sonography was performed to identify an RLS. DVT and PE were assessed by duplex ultrasonography and/or contrast-enhanced computed tomography. Proximal DVT (P-DVT) was defined as DVT in the popliteal, femoral, or iliac veins, and distal DVT (D-DVT) was defined as DVT at other locations. The patients were divided into three groups: CS with P-DVT and/or PE (P-DVT/PE) group; CS with D-DVT (D-DVT) group; and CS without DVT (no DVT) group. Results Seventy-two (37%) of 194 patients with CS had an RLS. The median time to first DVT examination from stroke onset was three days. Twenty-nine percent of CS patients with an RLS had DVT. The P-DVT/PE group comprised 8.3% of the CS patients with an RLS and included a larger number of patients with multi-territory infarction than the D-DVT group. The D-DVT and P-DVT/PE groups tended to be female and older, while the P-DVT/PE group tended to have pre-stroke disability. Conclusion CS patients, especially those with multi-territory lesions, should be immediately examined for DVT and PE.

Association of the incidence of venous air embolism on coronary computed tomography angiography with the intravenous access route preparation process

Venous air embolism (VAE) can be observed in the right heart system on contrast-enhanced computed tomography (CT), following injection of contrast media with a power injector system. Although most VAEs are mostly asymptomatic, they may result in paradoxical air embolism (PAE).To evaluate whether the incidence of VAE on coronary CT angiography is associated with the process of preparation of the intravenous access route.We retrospectively evaluated 692 coronary CT examinations at 3 institutions. Trained CT nurses placed an intravenous cannula in the forearm. Tubes connected to the cannula were prepared in the following ways: A, using an interposed three-way cock and a 20-mL syringe filled with normal saline to collect air contamination in the tube; B, through direct connection to the power injector system without the interposed 3-way cock; and C, using an interposed three-way cock and a 100-mL normal saline drip infusion bottle system to keep the tube patent. The incidence and location of VAE and preparation of intravenous injection were assessed.The overall incidence of VAE was 55.3% (383/692), most frequently observed in the right atrium (81.5%, 312/383). Its incidence varied significantly across the 3 techniques (A: 21.6% (35/162), B: 63.2% (237/375) and C: 71.6% (111/155); P < .001). No patient demonstrated any symptom associated with VAE.Using a 3-way cock with syringe demonstrated the lowest incidence of VAE on coronary CT angiography. It is thus recommended to reduce potential complication risks related to intravenous contrast media injection.

Lower limb vein thrombosis-induced pulmonary embolism and paradoxical multiple arterial embolisms: A case report with a 10-year follow-up

INTRODUCTION

Paradoxical embolism (PDE) refers to direct passage of venous thrombi into the arterial circulation through an arteriovenous shunt. It is well-known that the pulmonary thromboembolism (PTE) can cause opening of the foramen ovale leading to paradoxical arterial embolism. Long term follow up of PDE patient over 10 years was not reported in the literature.

PATIENT CONCERNS

A 57-year-old woman presented with initial symptoms of numbness/weakness and hypoxemia. Ultrasonography and pulmonary arteriography indicated pulmonary thromboembolism.

DIAGNOSIS

Pulmonary embolism and paradoxical multiple arterial embolism or acute PTE concomitant with paradoxical multiple arterial embolism.

INTERVENTIONS

Craniectomy and anticoagulation treatment was administered and the patient received low-dose warfarin therapy for 10 years.

OUTCOMES

The patient is currently stable with no abnormalities seen in the deep veins of the bilateral lower limbs. The international normalized ratio (INR) was controlled within the range of 1.20 to 1.51. As this is a 10-year follow-up case report, the patient has responded well to the treatment and has been followed-up. The follow-up has been annual and the patient has been stable CONCLUSION:: Low intensity and persistent anticoagulation therapy can inhibit blood thrombophilia and reduce the risk of bleeding. It is noteworthy that such an approach used effectively in this patient. To best our knowledge, it is first report for long term follow up PDE patient successfully over 10 years.

Echocardiographic features of PFOs and paradoxical embolism: a complicated puzzle

Patent foramen ovale (PFO) is a residual, oblique, slit or tunnel like communication in the atrial septum that persists into adulthood. It is usually an incidental finding with no clinical repercussions. Nevertheless, recent evidence supports the association between the presence of a PFO and a number of clinical conditions, most notably cryptogenic stroke (CS). There is enough evidence that paradoxical embolism is a mechanism which can explain this association. Patient characteristics and certain echocardiography-derived anatomical and hemodynamic features of PFO provide great assistance in estimating the probability of paradoxical embolism. In this review, we initially describe PFO embryology and anatomy. We extensively present the available data on clinical, anatomical and hemodynamic features of PFOs which have been correlated with increased likelihood of paradoxical embolism and recent evidence of therapeutic management.

[Paradoxical embolism: Myth or reality?]

Paradoxical embolism should be suspected in front of a clinical phenomenon of thromboembolism associated with an anatomical right-to-left shunt. Others potential cardiac sources of thromboembolism must be ruled out. Strokes constitute the most frequent clinical manifestations of paradoxical embolism. Right-to-left left shunts are in connection with intracardiac defects (atrial septal defect and patent foramen ovale) or pulmonary arteriovenous malformations. The probability that a discovered PFO is stroke-related can be evaluated by a score. Therapeutic approaches for secondary prevention of recurrent stroke include antithrombotic and/or percutaneous treatments. The choice strategy begins to be clearer with the recent results of randomized controlled studies.

Ebstein's Anomaly with Paradoxical Embolism to Lower Limb

Ebstein's anomaly (EA) is a rare congenital heart disease. Paradoxical embolism (PDE) may occur in EA due to associated atrial septal defect (ASD). An 18 year old male with EA presented with left lower limb ischemia due to PDE to the limb. No features of cerebral embolism was present. PDE is a potential complication of EA. High level of awareness is needed for early diagnosis of PDE in EA to save a limb in case of embolism to the extremity.

Patent foramen ovale and cryptogenic stroke: from studies to clinical practice: Position paper of the Italian Chapter, International Society Cardiovascular Ultrasound

BACKGROUND

Over the last two decades the interest on patent foramen ovale (PFO) as a cause of cardioembolism in cryptogenic stroke has tremendously increased, thanks to the availability of better techniques to diagnose cardiac right-to-left shunt by ultrasounds and of percutaneous means of PFO treatment with interventional techniques. Many studies have been published that have attempted to define diagnostic methodology, prognosis, and optimal treatment (pharmacological or percutaneous closure) of PFO patients with cryptogenic stroke. Unfortunately, even today, definitive evidence is still lacking, and clinical management is not consistent among cardiologists.

AIMS

This review aims to evaluate the role of PFO in cryptogenic stroke, the diagnostic accuracy of transcranial Doppler, contrast transthoracic and transesophageal echocardiography in the diagnosis of left-fright shunt and PFO; and discuss the indications to medical treatment and percutaneous closure of PFO.

METHODS

All studies published in the literature on PFO and cryptogenic stroke are considered and discussed.

RESULTS

We define an appropriate diagnostic and clinical management of PFO patients with cryptogenic stroke.

CONCLUSION

After many years of interest on PFO and many concluded studies, there are still no definitive data. However, we are on good track for an appropriate management of PFO patients and cryptogenic stroke.

Successful Percutaneous Transcatheter Patent Foramen Ovale Closure Through The Right Internal Jugular Vein Using Stiff Amplatzer Catheter With A Reshaped Tip

Percutaneous transcatheter closure of a patent foramen ovale (PFO) remains challenging when femoral venous approach is not available. We describe the successful closure of a PFO using the right internal jugular venous approach and a catheter delivery system with a reshaped tip in a patient with a PFO, recurrent stroke, recurrent gastrointestinal bleeding, bilateral deep venous thrombosis and thrombosed bilateral inferior vena cava filter.

[Paradoxical embolism: clinical situation and approaches to treatment]

The authors describe two clinical cases of paradoxical embolism of greater-circulation vessels in patients with thrombosis of deep veins of the lower extremities and patent foramen ovale, also discussing different variants of clinical course of paradoxical embolism, as well as approaches to treatment and prevention.

Large serpiginous thrombus straddling the patent foramen ovale and traversing through mitral and tricuspid valves into both ventricles: a therapeutic dilemma of impending paradoxical embolism and recurrent pulmonary embolism

A 51-year-old male with history of resected renal cell carcinoma and prior pulmonary embolism presented with tachypnea, tachycardia and progressive dyspnea on exertion. Chest computed tomography revealed bilateral acute pulmonary embolism. Transthoracic echocardiogram showed severe pulmonary hypertension with severe cor-pulmonale and presence of a large worm-like thrombus extending across the foramen ovale, entering both ventricles through the mitral and tricuspid valves. The risks of anti-coagulation, pharmacologic thrombolysis, and surgical thrombectomy, in a hemodynamically stable patient, posed a significant therapeutic dilemma. Ultimately, a collective decision was made to start anticoagulation, without incident. At 1 month follow up, complete resolution of the intracardiac thrombus, pulmonary hypertension, and cor-pulmonale were observed with full clinical recovery of the patient.

Ischemic stroke due to paradoxical embolism arising from a popliteal vein aneurysm

Popliteal vein aneurysm (PVA) is a very uncommon cause of stroke. We present the case of a 63-year-old, right-handed man who presented to the emergency department with transitory ischemic accident (left superior extremity regressive monoplegia). Complete etiologic work-up led to the discovery of both a patent foramen ovale associated with an septum interauricular aneurysm, and of a PVA without mural thrombus. The diagnosis of brain paradoxical embolism was retained. The unique potentially embolic cause was the presence of the PVA. We decided to treat the PVA surgically to avoid a further cerebral vascular episode. Although uncommon, venous etiology must be considered for stroke.

Paradoxical air embolism following central venous catheter removal

Central venous catheters are commonly used in the management of critically ill patients. This case report described a rare but potentially fatal complication of central venous catheter use. A 52-year-old man underwent mechanical aortic valve replacement for infective endocarditis. On day 8 postoperatively he accidentally removed his catheter and collapsed with symptoms and signs suggestive of a cerebral air embolism. A transthoracic echocardiogram showed air bubbles in both the right and left ventricles of the heart confirming the presence of a paradoxical air embolism.

Clinical outcomes after intravenous fibrinolysis in cryptogenic strokes with or without patent foramen ovale

BACKGROUND

Pivotal clinical trials suggest that intravenous (IV) recombinant tissue plasminogen activator (rt-PA) benefits stroke patients regardless of the underlying etiology. Paradoxical strokes, presumed to be caused by fibrin-rich clots originating in the venous circulation, may respond better to fibrinolysis than other ischemic stroke subtypes. In this study, we compared the response with IV rt-PA in paradoxical stroke patients and other stroke subtypes.

METHODS

In total, 486 patients treated with IV rt-PA at a single institution were retrospectively reviewed. Adjudication of stroke mechanism was based on chart review. Five major stroke mechanisms--cardioembolic, artery-to-artery emboli, lacunar, cryptogenic, and paradoxical--were identified by final diagnosis from chart reviews. Mimics, undefined etiology, and defined etiology not falling into the major mechanisms were excluded. Analysis of variance and general linear model were used to assess the differences between groups.

RESULTS

A total of 323 patients were analyzed. We found significant differences in clinical outcome between stroke mechanisms, including discharge National Institutes of Health Stroke Scale (NIHSS) (P=.007), discharge Rankin (P=.011), discharge disposition (P=.000), and infarct volume (P=.007). Post hoc analysis showed that cardioembolic patients had the worst outcomes (discharge NIHSS score 11.12±12.26), whereas paradoxical strokes had the best outcomes (discharge NIHSS score 3.67±4.90), but these did not approach statistical significance. However, regression analysis showed that 4 variables--congestive heart failure, admission NIHSS, age, and mean infarct volume--rather than stroke mechanism were the true predictors of poor outcome.

CONCLUSIONS

Paradoxical strokes had better outcomes after IV fibrinolysis than other ischemic stroke subtypes, but this difference is attributable to younger age and milder stroke severity on presentation.

Hereditary hemorrhagic telangiectasia with pulmonary arteriovenous malformations and embolic strokes treated successfully with video-assisted thoracoscopic resection

A 67-year-old hypoxic woman was admitted following two episodes of cerebral infarction. Based on the clinical presentation and radiological findings, a diagnosis of hereditary hemorrhagic telangiectasia was made and the cerebral ischemic complications were considered to have been caused by paradoxical embolizations related to pulmonary arteriovenous malformations (PAVMs). We performed video-assisted thoracoscopic surgery (VATS) and identified turbulent thrombi in one of the PAVMs that were capable of circulating systemically and inducing embolic strokes. The condition of the patient improved immediately following VATS. This case suggests that VATS may be a preferred therapeutic option in the treatment of patients with PAVM accompanying recurrent episodes of life-threatening complications such as strokes.