Does patent foramen ovale closure have an anti-arrhythmic effect? A meta-analysis

European Stroke Organisation (ESO) Guidelines on the diagnosis and management of patent foramen ovale (PFO) after stroke

Patent foramen ovale (PFO) is frequently identified in young patients with cryptogenic ischaemic stroke. Potential stroke mechanisms include paradoxical embolism from a venous clot which traverses the PFO, in situ clot formation within the PFO, and atrial arrhythmias due to electrical signalling disruption. The purpose of this guideline is to provide recommendations for diagnosing, treating, and long-term managing patients with ischaemic stroke and PFO. Conversely, Transient Ischaemic Attack (TIA) was not considered an index event in this context because only one RCT involved TIA patients. However, this subgroup analysis showed no significant differences between TIA and stroke outcomes. The working group identified questions and outcomes, graded evidence, and developed recommendations following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach and the European Stroke Organisation (ESO) standard operating procedure for guideline development. This document underwent peer-review by independent experts and members of the ESO Guideline Board and Executive Committee. The working group acknowledges the current evidentiary gap in delineating an unequivocal diagnostic algorithm for the detection of PFO. Although transoesophageal echocardiography is conventionally held as the most accurate diagnostic tool for PFO identification, its status as the 'gold standard' remains unsubstantiated by rigorously validated evidence. We found high-quality evidence to recommend PFO closure plus antiplatelet therapy in selected patients aged 18-60 years in whom no other evident cause of stroke is found but a PFO (i.e. PFO-associated stroke). The PASCAL classification system can be used to select such candidates for PFO closure. Patients with both a large right-to-left shunt and an atrial septal aneurysm benefit most from PFO closure. There is insufficient evidence to make an evidence-based recommendation on PFO closure in patients older than 60 and younger than 18 years. We found low quality evidence to suggest against PFO closure in patients with unlikely PFO-related stroke according to the PASCAL classification, except in specific scenarios (Expert Consensus). We suggest against long-term anticoagulation in patients with PFO-associated stroke unless anticoagulation is indicated for other medical reasons. Regarding the long-term AF monitoring after PFO closure, the working group concluded that there remains significant uncertainty regarding the risks and benefits associated with the use of long-term cardiac monitoring, such as implantable loop recorders. This document provides additional guidance, in the form of evidence-based recommendations or expert consensus statements, on diagnostic methods for PFO detection, and medical management after PFO closure.

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.

Uncertainties and Controversies in the Management of Ischemic Stroke and Transient Ischemic Attack Patients With Patent Foramen Ovale

Multiple randomized clinical trials have demonstrated the benefit of patent foramen ovale closure over medical therapy alone for patients who have had a stroke that has been attributed to the patent foramen ovale. Nevertheless, there are many areas of uncertainty and controversy related to patient selection, pathophysiology, diagnosis, and treatment. We summarize the available data on these challenging topics and attempt to provide some clarity and future directions for clinicians and investigators.

Shorter visual aura characterizes young and middle-aged stroke patients with migraine with aura

OBJECTIVE

To identify the clinical profile and aura characteristics of patients with Migraine with Aura (MwA) having acute cerebral ischemia, we compared stroke phenotype and risk factors in stroke patients with (S+MwA+) or without (S+MwA-) MwA and aura features in MwA patients with (S+MwA+) or without (S-MwA+) stroke.

METHODS

In this retrospective multicenter case-control study, we reviewed stroke phenotypes and vascular risk factors in S+MwA+ and S+MwA- patients younger than 60 years and risk factors and aura type, duration, onset age, and the frequency in the previous year in S+MwA+ patients and S-MwA+ subjects matched for age and disease history, investigated for patent foramen ovale (PFO).

RESULTS

539 stroke (7.7% S+MwA+) and 94 S-MwA + patients were enrolled. S+MwA+ patients were younger (p =.0.004) and more frequently presented PFO [OR 4.89 (95% CI 2.12-11.27)], septal interatrial aneurism [OR 2.69 (95% CI 1.15-6.27)] and cryptogenic ischemic stroke (CIS) [OR 6.80 (95% CI 3.26-14.18)] than S+MwA- subjects. Significant atherosclerosis was not detected in S+MwA+ patients. Compared to S-MwA+, S+MwA+ patients were characterized by visual [OR 3.82 (95% CI 1.36-10.66)] and shorter-lasting (20.0 min IQr 13.1 vs 30.0 min IQr 25.0; p < 0.001) aura, and PFO [OR 1.26 (95% CI 1.03-1.54)]. Regression analysis evidenced that only shorter aura duration associated with stroke (p = 0.001). High-risk PFO was equally represented in S+MwA-, S+MwA+, S-MwA+ groups.

CONCLUSIONS

Shorter visual aura and CIS characterize MwA patients with stroke. Although more prevalent, PFO can not be considered the main responsible for the increased stroke risk in MwA patients but as a part of a complex multifactorial condition.

Network meta-analysis on patent foramen ovale: is a stroke or atrial fibrillation worse?

OBJECTIVE

Systematic reviews suggest that patent foramen ovale closure (PFOc) is performed percutaneously with low complication rates. We did a network meta-analysis (NMA) comparing devices for PFO closures, evaluating safety and efficacy of transcatheter PFOc in preventing neurological events in patients with stroke when compared with medical therapy (MT), and assessing risk of atrial fibrillation (AF).

METHODS

We searched 3 databases (MEDLINE, EMBASE, CENTRAL/CCTR) identifying six randomized controlled trials from 2012 until December 2019. We performed a Bayesian NMA; number-needed-to-treat and number-needed-to-harm were derived by applying the estimated odds ratios (ORs). The likelihood of being helped or harmed (LHH) was evaluated to estimate the risk-effectiveness balance.

RESULTS

The 3560 patients allocated to PFOc were less subject to a stroke than patients with MT. The overall ORs of PFOc versus MT were 0.41 with fixed-effects, and 0.22 with random-effects model. NMA proves that PFOc induces AF episodes significantly higher than MT, even when analysis is limited to only new episodes of "serious AF." LHH (0.68 fixed-effects, 0.79 random-effects) showed that strokes saved are less than cases of AFs added. By considering only serious AF, strokes saved are higher than serious AFs induced by the PFOc (LHH was 3.46 and 4.00 respectively).

CONCLUSIONS

NMA supported PFOc in patients with cryptogenic stroke, confirming that devices are better than MT, but increase the risk of AF by over 2/4 times (serious or unserious AF). Considering serious AFs (real risky clinical condition), patients have more advantages in being treated, since LHH is ≥ 3-4.

[Patent foramen ovale with a license to kill]

A patent foramen ovale (PFO) is present in about one of four, and one of its dangerous forms (large or associated with atrial septal aneurysm, Eustachian valve, or Chiari network) in one of twenty people. About 140 years ago, the PFO was shown to have the potential to result in death due to stroke and also myocardial infarction. The described decrease of the prevalence of a PFO with age may be a consequence of this. Therefore, it comes somewhat as a surprise that the PFO is taken rather lightly by the medical community. Percutaneous PFO closure with implantable devices has been around for over two decades and since then has proven to be the simplest and safest technique in interventional cardiology. Nonetheless, it is rarely applied and not recommended in current guidelines except for a few situations. Countless nonrandomised comparisons have invariably pointed to a clinical benefit of PFO closure in the secondary prevention of paradoxical cerebral events in patients with or without competitive reasons for stroke. Even a survival benefit of PFO closure was shown in a comparison over 10 years. However, the first three publications of randomised trials were not significant in the protocolled sense. PFO closure did reduce recurrent events compared to medical therapy by up to 80% but the statistical significance postulated was only reached in one of the three trials when the results were analyzed as treated or per predefined subgroups, like patients with atrial septal aneurysm, large PFO, or all PFO closure patients compared to treatment with acetylsalicylic acid only. Recently, a preplanned longer-term analysis of this trial and two additional randomised trials including higher risk PFOs reached the hypothesised statistical significance. This may be a turning point in the attitude towards PFO closure. In addition, PFO closure improves migraine and dyspnoea in certain patients. It appears, though, that it will take time until the full potential of PFO closure will be reflected in respective guidelines and reimbursement algorithms and adequately exploited by referring physicians (mostly neurologists) and interventional cardiologists. This reluctance will continue to cost innumerable preventable strokes, myocardial infarctions, and deaths around the world. The low risk of PFO closure must be weighed against even death if a PFO is left open; it is much more likely that one regrets not having closed a PFO than having closed it.

Computational Flow Dynamic Analysis of Right and Left Atria in Patent Foramen Ovale: Potential Links with Atrial Fibrillation

Background

An impairment of the left atrial function similar to that usually observed in atrial fibrillation (AF) has been observed also in patients with patent foramen ovale (PFO) and permanent right-to-left shunting (RLS).

Methods

We reconstructed the geometrical model of right atrium (RA), PFO, left atrium (LA) and left atrial appendage (LAA) of 65 patients with mild (36 patients mean age 45.5±6.8 years, 24 females) or permanent (29 patients, mean age 45.1±5.3 years, 21 females) RLS using anatomical data obtained by transoesophageal echocardiography (TEE) and cardiac MRI, performed as a part of our institutional screening protocol for paradoxical embolism. Using computational fluid dynamic analysis (CFD) we assessed the vorticity magnitude in both the LA and LAA to analyse a possible rheological relationship between PFO and AF.

Results

The anatomical models, in terms of dimensions, were comparable among the patients with mild and permanent RLS. A higher vorticity magnitude was observed in the mild shunt both in the LA (101.12±21.3 vs 88.3±22.6, p=0.02) and LAA (62±14.4 vs 32.4±12.3, p<0.01) when compared to the permanent R-L shunting.

Conclusion

The lower vorticity magnitude across the LA and LAA in patients with permanent RLS suggests a possible higher stagnation of the blood in these anatomical sites, similarly as previously observed in patients with AF.

Right to left shunting through communications between the left superior intercostal vein tributaries and the left atrium: a potential cause of paradoxical embolism

OBJECTIVES

To investigate the role of collateral venous pathways between the left brachiocephalic vein (LBV) and the left atrium through an arcade comprising the left superior intercostal vein (LSICV), left vertical vein (LVV), and pulmonary veins as a potential cause of paradoxical embolism.

METHODS

A retrospective search was performed to find symptomatic patients with negative work up for paradoxical emboli whose chest CT or MR angiography by left arm contrast injection showed a visible right to left shunt through the LSICV/LVV collateral pathway (symptomatic group). We also evaluated the characteristics of this collateral pathway in 150 chest CT angiographies from general referrals (comparison group).

RESULTS

We found 7 symptomatic patients. Initial presentations included neurological symptoms in all patients and episodes of hypoxemia in three patients. Communications between the LBV and left atrium through the LSICV/LVV pathway was seen is all 7 cases and confirmed by transesophageal echocardiography in two. An abnormal LBV was seen in 6 cases (absence in one, stenosis in 5). Moderate superior vena cava stenosis was seen in one and acute right subclavian vein thrombosis in one. Six patients had past history of an upper extremity central line placement. In the comparison group, LSICV was seen in 73 (48%), connecting to the hemiazygos vein in 41, to a LVV in 19 and to the left atrium in 7.

CONCLUSION

LSICV/LVV collaterals are common and can be a potential route for paradoxical emboli especially when stenosis of a draining vein such as LBV exists.

Modern management of a patent foramen ovale

A patent foramen ovale (PFO) has been associated with medical conditions such as cryptogenic stroke, migraine with aura, and decompression illness. Whether closure of the PFO has clinical benefit has been suggested from registry studies, but not yet confirmed in multiple randomized trials. Methods of diagnosis of a PFO and a summary of the current evidence for treatment is presented and discussed as a guide to patient-centred decision-making.