Patent foramen ovale (PFO) closure versus medical therapy for prevention of recurrent stroke in patients with prior cryptogenic stroke: A systematic review and meta-analysis of randomized controlled trials

A whole-exome sequencing study of patent foramen ovale: investigating genetic variants and their association with cardiovascular disorders

Background

Patent foramen ovale (PFO) has a genetic predisposition and is closely associated with cryptogenic stroke (CS), migraine, decompression sickness, and hypoxemia. Identifying PFO-related mutant genes through whole-exome sequencing (WES) can help in the early recognition of cardiovascular genetic risk factors, guide timely clinical intervention, and reduce the occurrence of cardiovascular events.

Methods

We analyzed mutant genes from ClinVar and OMIM databases. WES was performed on 25 PFO patients from Zhejiang Provincial Hospital of Chinese Medicine. Pathogenicity of variants was evaluated using American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology. (AMP) guidelines.

Results

In ClinVar (4 Feb 2023), 113 coding gene mutations were found, including 83 associated with PFO. From OMIM (18 Apr 2023), 184 gene mutations were analyzed, with 110 mutant coding genes. WES identified pathogenic mutations in two of 25 PFO patients (8%). LDLR, SDHC, and NKX2-5 genes were linked to PFO and primarily involved in myocardial tissue function. NKX2-5 may play a crucial role in PFO development, interacting with NOTCH1, GATA4, MYH6, SCN5A signaling pathways regulating cardiomyocyte characteristics.

Conclusion

We identified pathogenic mutations in LDLR, SDHC, and NKX2-5 genes, implying their role in PFO development. Functional enrichment analysis revealed NKX2-5's interaction with signaling pathways regulating cardiomyocyte function. These findings enhance our understanding of PFO's genetic basis, suggesting potential therapeutic targets for future research.

Atrial Fibrillation After Patent Foramen Ovale Closure: Incidence, Pathophysiology, and Management

This comprehensive review explores the incidence, pathophysiology, and management of atrial fibrillation (AF) following percutaneous closure of patent foramen ovale (PFO). Although AF is considered a common adverse event post PFO closure, its incidence, estimated at <5%, varies based on monitoring methods. The review delves into the challenging task of precisely estimating AF incidence, given subclinical AF and diverse diagnostic approaches. Notably, a temporal pattern emerges, with peak incidence around the 14th day after closure and a subsequent decline after the 45th day, mimicking general population AF trends. The pathophysiological mechanisms behind post PFO closure AF remain elusive, with proposed factors including local irritation, device-related interference, tissue stretch, and nickel hypersensitivity. Management considerations encompass rhythm control, with flecainide showing promise, and anticoagulation tailored to individual risk profiles. The authors advocate for a personalized approach, weighing factors like age, comorbidities, and device characteristics. Notably, postclosure AF is generally considered benign, often resolving spontaneously within 45 days, minimizing thromboembolic risks. Further studies are required to refine understanding and provide evidence-based guidelines.

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.

Cervical Artery Dissection and Patent Foramen Ovale in Juvenile Stroke: Causality or Casuality? A Familiar Case Report

Cervical artery dissection (CAD) and Patent Foramen Ovale (PFO) are important causes of stroke in young patients. Although PFO is considered an independent risk factor for cerebral infarction in young adults with cryptogenic stroke, other concomitant causes may be necessary to cause brain injury. PFO could be a predisposing factor of stroke through several mechanisms including paradoxical embolism from a venous source, thrombus formation in atrial septum, or atrial arrhythmias causing cerebral thromboembolism. The pathophysiology of CAD is poorly understood and includes both constitutional and environmental factors. A causal association is often difficult to establish, as other predisposing factors may also play a role in CAD etiopathogenesis. We present a family with ischemic stroke (a father and his three daughters), in which the two different stroke causes are present. We hypothesized that a paradoxical embolism caused by PFO, associated with arterial wall disease, in the presence of a procoagulant state, could produce arterial dissection and then stroke.

Patent Foramen Ovale and Cryptogenic Stroke: Integrated Management

Patent foramen ovale (PFO) is a common cardiac abnormality with a prevalence of 25% in the general population. PFO has been associated with the paradoxical embolism causing cryptogenic stroke and systemic embolization. Results from clinical trials, meta-analyses, and position papers support percutaneous PFO device closure (PPFOC), especially if interatrial septal aneurysms coexist and in the presence of large shunts in young patients. Remarkably, accurately evaluating patients to refer to the closure strategy is extremely important. However, the selection of patients for PFO closure is still not so clear. The aim of this review is to update and clarify which patients should be considered for closure treatment.

Sex differences in baseline profiles and short-term outcomes in patients undergoing closure of patent foramen ovale

Objectives

Although sex differences have been emphasized in stroke and congenital heart disease, there has been limited investigation into their role in patent foramen ovale (PFO) closure for secondary prevention of stroke. We aimed to explore differences by sex in baseline profiles, procedural characteristics, and short-term outcomes of patients undergoing transcatheter PFO closure.

Methods

Data of adult patients undergoing transcatheter PFO closure at the Toronto General Hospital from 1997 to 2017 was retrospectively analyzed. Baseline information included demographic characteristics, medical history, diagnostic, and procedural information, and periprocedural complications. Post-closure outcomes were captured at index hospitalization and during the first follow-up.

Results

From 1031 patients in the cohort sample, 80.7 % underwent closure for cryptogenic stroke and 44.7 % (n = 461) were females. We observed significant sex-related differences in baseline characteristics; females were younger, less likely to have a history of smoking, and less likely to have several cardiovascular risk factors at baseline (p < 0.05). The median time to first follow-up was 89 days for both groups. Recurrent stroke was observed in 0.1 % and TIA observed in 0.4 % of in the 'cryptogenic stroke/TIA' group; in the 'other indications' group, 1.4 % stroke and no TIA were reported. No significant differences were present between sexes.

Conclusions

There were no differences in procedural and short-term outcomes between males and females undergoing transcatheter PFO closure, but significant baseline differences in risk factors were identified. There is a critical need for long-term, systematic studies to understand sex and gender differences in the PFO population.

Patent foramen ovale and perioperative stroke in noncardiac surgery: a systematic review and meta-analysis

BACKGROUND

Patent foramen ovale (PFO) is associated with perioperative stroke in noncardiac surgery. The magnitude of this association was assessed in a systematic review and meta-analysis.

METHODS

Electronic databases were searched up to June 2022 for studies assessing the association between patent foramen ovale and perioperative stroke in adult patients undergoing noncardiac surgery. The primary analysis was limited to studies reporting effect estimates adjusted for significant clinical confounders. We calculated the adjusted odds ratio (aOR) and 95% confidence interval (CI).

RESULTS

We included nine retrospective and two prospective observational studies, including 21 257 082 patients. The presence of a patent foramen ovale was independently associated with stroke at 30 days after surgery (aOR=6.68 [95% CI: 3.51-12.73]; P<0.001) and at longest follow-up available (aOR=7.36 [95% CI: 3.56-15.21]; P<0.001). The odds of stroke at 30 days varied according to surgical specialty: neurosurgery (aOR=4.52 [95% CI: 3.17-6.43]), vascular surgery (aOR=7.15 [95% CI: 2.52-20.22]), thoracic surgery (aOR=10.64 [95% CI: 5.97-18.98]), orthopaedic surgery (aOR=11.85 [95% CI: 5.38-26.08]), general surgery (aOR=14.40 [95% CI: 10.88-19.06]), and genitourinary surgery (aOR=17.28 [95% CI: 10.36-28.84]).

CONCLUSIONS

The presence of a patent foramen ovale is associated with a large and consistent increase in odds of stroke across all explored surgical settings. Prospective trials should further explore this association by systematically assessing patent foramen ovale and stroke prevalence and identifying a specific population at risk. This is crucial for the elaboration of prevention plans and may improve perioperative outcomes.

Advances in Percutaneous Patent Foramen Ovale Closure: From the Procedure to the Echocardiographic Guidance

Percutaneous patent foramen ovale (PFO) closure by traditional, double disc occluder devices was shown to be safe for patients with PFO, and more effective than prolonged medical therapy in preventing recurrent thromboembolic events. The novel suture-mediated “deviceless” PFO closure system overcomes most of the risks and limitations associated with the traditional PFO occluders, appearing to be feasible in most interatrial septum anatomies, even if data about its long-term effectiveness and safety are still lacking. The aim of the present review was to provide to the reader the state of the art about the traditional and newer techniques of PFO closure, focusing both on the procedural aspects and on the pivotal role of transesophageal echocardiography (TEE) in patient’s selection, peri-procedural guidance, and post-interventional follow-up.

Comparison of right-to-left shunt characteristics in cryptogenic embolic ischemic stroke and non-cardioembolic ischemic stroke

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.

Transcatheter Closure of PFO and ASD: Multimodality Imaging for Patient Selection and Perioperative Guidance

Transcatheter closure of patent foramen ovale (PFO) and secundum type atrial septal defect (ASD) are common transcatheter procedures. Although they share many technical details, these procedures are targeting two different clinical indications. PFO closure is usually considered to prevent recurrent embolic stroke/systemic arterial embolization, ASD closure is indicated in patients with large left-to-right shunt, right ventricular volume overload, and normal pulmonary vascular resistance. Multimodality imaging plays a key role for patient selection, periprocedural monitoring, and follow-up surveillance. In addition to routine cardiovascular examinations, advanced neuroimaging studies, transcranial-Doppler, and interventional transesophageal echocardiography/intracardiac echocardiography are now increasingly used to deliver safely and effectively such procedures. Long-standing collaboration between interventional cardiologist, neuroradiologist, and cardiac imager is essential and it requires a standardized approach to image acquisition and interpretation. Periprocedural monitoring should be performed by experienced operators with deep understanding of technical details of transcatheter intervention. This review summarizes the specific role of different imaging modalities for PFO and ASD transcatheter closure, describing important pre-procedural and intra-procedural details and providing examples of procedural pitfall and complications.

[Patent foramen ovale. An update for primary care]

Patent foramen ovale (FOP) is the most prevalent cause of cryptogenic strokes in people under 60 years old. Although it is usually asymptomatic, it has a high risk of producing paradoxical embolism and, therefore, stroke with indeterminate outcomes. The study should be started based on clinical suspicion, and includes a multidisciplinary assessment and a determination of the type of treatment to be performed. The therapeutic possibilities range from conservative treatment (indefinite antithrombotic treatment), to its percutaneous closure (currently the most widely used). The first objective is to decrease the number of stroke recurrences. Conservative treatment should be reserved for those cases of low embolic risk. The risk assessment must be individualised, fundamentally based on the anatomical characteristics of the FOP and the patient clinic picture. The use of the RoPE risk scale (The Risk of Paradoxical Embolism) should be a tool to consider.

Reverse takotsubo cardiomyopathy caused by patent foramen ovale-related cryptogenic stroke: a case report

Background

Reverse takotsubo cardiomyopathy (rTTC) is recognized as an atypical type of TTC. It has been suggested that neurological events are typical trigger of rTTC, especially in young individuals.

Case summary

In this case report, we describe a 16-year-girl who presented with neurological deficits due to embolic stroke and acute heart failure. Transthoracic echocardiography on admission revealed a severely reduced left ventricular (LV) function with akinesis of basal to mid LV, but normal contraction in apex. Coronary computed tomography angiography confirmed unobstructed coronary arteries. Two weeks later, her LV wall motion and ejection fraction were completely normalized. Transthoracic echocardiography and transoesophageal echocardiography demonstrated no evidence of intracardiac thrombus but showed a patent foramen ovale (PFO) with large shunt. After thorough work-up and brain–heart team discussion, we concluded that the patient developed rTTC due to cryptogenic stroke related with her PFO. She underwent percutaneous PFO closure for secondary prevention with good clinical course.

Discussion

Reverse TTC is a rare condition. It should be considered in stroke patients with acute heart failure. Quick diagnosis and management with brain–heart team is crucial for better prognosis.

The role of device closure of patent foramen ovale in patients with cryptogenic stroke

One of the most frequent causes of cardiac embolism in cryptogenic stroke is a paradoxical embolus, which originate from systemic venous source though an unidentified patent foramen ovale (PFO). PFO is a common finding in the general population with a prevalence of 25% to 30%. Transcatheter PFO device closure is known to be feasible and safety treatment for such patients. In recent years, several randomized controlled trials (RCTs) have been conducted to address the superiority of PFO closure over medical therapy alone in the prevention of stroke recurrence in patients with PFO. In contrast to findings from early 3 RCTs, recent 4 RCTs could successfully show the benefits of PFO device closure compared with medical therapy, with less peri- and postprocedural complication. Based on these data, PFO device closure is recommended to carefully select cryptogenic stroke patients aged from 18 to 65 years, with a high probability of a causal role of the PFO in stroke events. However, it is still uncertain whether PFO closure is superior to oral anticoagulants therapy in these patients. Therefore, further prospective randomized trials are needed to address the efficacy of PFO device closure to oral anticoagulants therapy.

Multiorgan paradoxical embolism in an elderly female with a patent foramen ovale: a case report

Paradoxical embolism is an uncommon cause of arterial occlusion with a high mortality burden. Current evidence suggests that patent foramen ovale is the most important etiological factor of paradoxical embolism, by acting as a pathway for a thromboembolic material originating from the peripheral veins, passing through the lungs and entering the systemic circulation. Here we present a case of paradoxical embolism in the mesenteric and renal arteries associated with pulmonary embolism and deep vein thrombosis in an elderly woman with no predisposing risk factor. A diagnosis of paradoxical embolism was considered and the presence of a patent foramen ovale was consequently confirmed with a transesophageal echocardiography. Urgent thrombolysis saved the life of the patient. Paradoxical embolism represents an emergency and therefore prompt diagnosis and initiation of therapy may prevent adverse outcomes.

Updated Meta-analysis on the Closure of Patent Foramen Ovale in Reduction of Stroke Rates: the DEFENSE-PFO Trial Does not Change the Scenario

Objective

We aimed to analyze whether patent foramen ovale (PFO) closure reduces the risk of stroke, assessing also some safety outcomes after the publication of a new trial.

Introduction

The clinical benefit of closing a PFO has been an open question, so it is necessary to review the current state of published medical data in regards to this subject.

Methods

MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles were used to search for randomized controlled trials (RCTs) that reported any of the following outcomes: stroke, death, major bleeding or atrial fibrillation. Six studies fulfilled our eligibility criteria and included 3560 patients (1889 for PFO closure and 1671 for medical therapy.

Results

The risk ration (RR) for stroke in the “closure” group compared with the “medical therapy” showed a statistically significant difference between the groups, favouring the “closure” group (RR 0.366; 95%CI 0.171–0.782, P=0.010). There was no statistically significant difference between the groups regarding the safety outcomes, death and major bleeding, but we observed an increase in the risk of atrial fibrillation in the “closure” group (RR 4.131; 95%CI 2.293–7.443, P<0.001). We also observed that the larger the proportion of effective closure, the lower the risk of stroke.

Conclusion

This meta-analysis found that stroke rates are lower with percutaneously implanted device closure than with medical therapy alone, being these rates modulated by the rates of hypertension, atrial septal aneurysm and effective closure. The publication of a new trial did not change the scenario in the medical literature.

Long-term biocompatibility of fluorescent diamonds-(NV)-Z~800 nm in rats: survival, morbidity, histopathology, particle distribution and excretion studies (part IV)

BACKGROUND

Thromboembolic events are a major cause of heart attacks and strokes. However, diagnosis of the location of high risk vascular clots is hampered by lack of proper technologies for their detection. We recently reported on bio-engineered fluorescent diamond-(NV)-Z~800nm (FNDP-(NV)) conjugated with bitistatin (Bit) and proven its ability to identify iatrogenic blood clots in the rat carotid artery in vivo by Near Infra-Red (NIR) monitored by In Vivo Imaging System (IVIS).

PURPOSE

The objective of the present research was to assess the in vivo biocompatibility of FNDP-(NV)-Z~800nm infused intravenously to rats. Multiple biological variables were assessed along this 12 week study commissioned in anticipation of regulatory requirements for a long-term safety assessment.

METHODS

Rats were infused under anesthesia with aforementioned dose of the FNDP-(NV), while equal number of animals served as control (vehicle treated). Over the 12 week observation period rats were tested for thriving, motor, sensory and cognitive functions. At the termination of study, blood samples were obtained under anesthesia for comprehensive hematology and biochemical assays. Furthermore, 6 whole organs (liver, spleen, brain, heart, lung and kidney) were collected and examined ex vivo for FNDP-NV) via NIR monitored by IVIS and histochemical inspection.

RESULTS

All animals survived, thrived (no change in body and organ growth). Neuro-behavioral functions remain intact. Hematology and biochemistry (including liver and kidney functions) were normal. Preferential FNDP-(NV) distribution identified the liver as the main long-term repository. Certified pathology reports indicated no outstanding of finding in all organs.

CONCLUSION

The present study suggests outstanding biocompatibility of FNDP-(NV)-Z~800nm after long-term exposure in the rat.

Secondary prevention of cryptogenic stroke in patients with patent foramen ovale: a systematic review and meta-analysis

The aim of our study is to compare patent foramen ovale (PFO) closure versus medical treatment and antiplatelet versus anticoagulant therapy in patients with cryptogenic stroke (CS) and PFO. We conducted a systematic review and meta-analysis with trial sequential analysis (TSA) of randomized trials. Primary outcomes are stroke or transient ischemic attack (TIA) and all-cause mortality. Secondary outcomes are peripheral embolism, bleeding, serious adverse events, myocardial infarction and atrial dysrhythmias. We performed an intention to treat meta-analysis with a random-effects model. We include six trials (3677 patients, mean age 47.3 years, 55.8% men). PFO closure is associated with a lower recurrence of stroke or TIA at a mean follow-up of 3.88 years compared to medical therapy [risk ratio (RR) 0.55, 95% CI 0.38-0.81; I² = 40%]. The TSA confirms this result. No difference is found in mortality (RR 0.74, 95% CI 0.35-1.60; I² = 0%), while PFO closure is associated with a higher incidence of atrial dysrhythmias (RR 4.55, 95% CI 2.16-9.60; I² = 25%). The rate of the other outcomes is not different among the two groups. The comparison between anticoagulant and antiplatelet therapy shows no difference in terms of stroke recurrence, mortality and bleeding. There is conclusive evidence that PFO closure reduces the recurrence of stroke or TIA in patients younger than 60 years of age with CS. More data are warranted to assess the consequences of the increase in atrial dysrhythmias and the advantage of PFO closure over anticoagulants.

State-of-the-Art Atrial Septal Defect Closure Devices for Congenital Heart

This article describes current devices and indications for transcatheter device closure of atrial septal defect (TC-ASD) and patent foramen ovale in children and young adults. TC-ASD has a proven record of efficacy and safety, but device erosion raises questions about the relative safety of TC-ASD versus operative open heart surgical ASD closure. New devices for ASD closure with properties to reduce risk of erosion are being developed. Recent studies demonstrating superiority of patent foramen ovale device closure over medical therapy for cryptogenic stroke may lead to changes in practice for structural/interventional cardiologists. Care should be taken in extrapolating data to children and younger adults.