The Case for Selective Patent Foramen Ovale Closure After Cryptogenic Stroke

Patent foramen ovale closure review: decades of research and the evolution of the evidence

Background

A quarter of the population suffers from patent foramen ovale, a form of interatrial shunt. It has been linked to cryptogenic strokes and is a common cause of paradoxical embolism.

Main text

The benefit of closing the patent foramen ovale in cryptogenic stroke patients aged 18-60 years to prevent recurrent strokes, particularly in those with large shunts or associated atrial septal aneurysms, was recently demonstrated. It is a relatively safe procedure that necessitates post-operative anticoagulation, but it has been linked to new-onset atrial fibrillation of uncertain significance. The effectiveness of patent foramen closure depends on patient selection, and prediction scores such as the Risk of Paradoxical Embolism (RoPE) score should be used. Newer closure devices, such as bioabsorbable devices like the Biostar system and ‘device-less’ devices like the Noble Stitch, are becoming more common due to their lower operative risks. The use of such devices in future trials, as well as careful case selection, could improve the acceptability of patent foramen ovale closure in the general population, removing the need for perioperative anticoagulation.

Conclusion

Individuals aged 18-60 years with cryptogenic stroke who have adverse patent foramen ovale morphology on imaging should be offered patent foramen ovale closure, preferably using the newer closure devices. More studies are needed to determine the significance of periprocedural atrial fibrillation after device closure.

How Old is Too Old? Closure of Patent Foramen Ovale in Older Patients

Percutaneous closure of a patent foramen ovale (PFO) reduces the risk of recurrent cryptogenic stroke specifically in younger patients. The three randomized controlled trials that led to the widespread adoption of PFO closure excluded patients over the age of 60 years. Older patients frequently have other cardiac and vascular conditions that are common risk factors for stroke, whereas paradoxical embolism through a PFO is relatively rare. Younger patients theoretically benefit the most from closure due to longer lifetime exposure risk and absence of other traditional risk factors. PFO in older patients with cryptogenic strokes is often encountered in clinical practice, making up an increasing number of cardiology referrals, yet cardiologists lack guidelines and evaluation tools for these patients. This review explores the history of PFO closure – emphasizing data in older adults – and discusses the evaluation and treatment of older people with cryptogenic stroke and PFO while further trials in this important population are awaited.

Late recognition of Gore Helex atrial septal occluder fracture and migration

Patent foramen ovale (PFO) closure is indicated in cryptogenic stroke. Percutaneous PFO closure is both feasible and highly efficacious with low incidence of device-related complications. When complications occur, they are usually discovered within 6 weeks of device deployment. We describe the case of a partially embolised and fractured Gore Helex Septal Occluder device recognised nearly 9 years after placement requiring surgical explant. <Learning objective: Device-related complications with patent foramen ovale closure devices are exceeding rare. Our case highlights the need for continued long-term device monitoring with periodic imaging given the ongoing risk for device-related complications.>.

Prognosis of Cryptogenic Stroke With Patent Foramen Ovale at Older Ages and Implications for Trials: A Population-Based Study and Systematic Review

Importance

Patent foramen ovale (PFO) closure may prevent recurrent stroke after cryptogenic transient ischemic attack (TIA) or stroke (TIA/stroke) in patients aged 60 years or younger. Patent foramen ovale is associated with cryptogenic stroke in the older population, but risk of recurrence is unknown. Data on prognosis of patients receiving medical treatment at older ages (≥60 years) are essential to justify trials of PFO closure.

Objective

To examine the age-specific risk of recurrence in patients with cryptogenic TIA/stroke with PFO.

Design, Setting, and Participants

A prospective study was nested in the population-based Oxford Vascular Study between September 1, 2014, and March 31, 2019, with face-to-face follow-up for 5 years. A total of 416 consecutive patients with a diagnosis of cryptogenic TIA or nondisabling stroke, screened for PFO at a rapid-access TIA/stroke clinic, were included. A systematic review and meta-analysis of cohort studies reporting on ischemic stroke recurrence after cryptogenic TIA/stroke in patients with PFO who were receiving medical therapy alone, or with PFO vs no-PFO was conducted. Sample size calculation for future trials on PFO closure was performed for patients aged 60 years or older.

Exposures

Patent foramen ovale and age as modifiers of risk of recurrent stroke after cryptogenic TIA/stroke in patients receiving only medical therapy.

Main Outcomes and Measures

Risk of ischemic stroke recurrence in patients with cryptogenic TIA/stroke and PFO receiving medical therapy only, and in patients with vs without PFO, stratified by age (<65 vs ≥65 years), as well as sample-size calculation for future trials of PFO closure in patients aged 60 years or older.

Results

Among the 153 Oxford Vascular Study patients with PFO (mean [SD] age, 66.7 [13.7] years; 80 [52.3%] men), recurrent ischemic stroke risk (2.05 per 100 patient-years) was similar to the pooled estimate from a systematic review of 23 other studies (9 trials and 14 observational studies) (2.00 per 100 patient-years; 95% CI, 1.55-2.58). However, there was heterogeneity between studies (P < .001 for heterogeneity), owing mainly to risk increasing with mean cohort age (meta-regression: R2 = 0.31; P = .003). In the pooled analysis of 4 studies including patients with or without PFO, increased risk of stroke recurrence with PFO was seen only at age 65 years or older (odds ratio, 2.5; 95% CI, 1.4-4.2; P = .001 for difference; P = .39 for heterogeneity). The pooled ischemic stroke risk was 3.27 per 100 patient-years (95% CI, 2.59-4.13) in 4 cohorts with mean age 60 years or older. Assuming the more conservative 2.0 per 100 patient-years ischemic stroke risk in the PFO nonclosure arms of future trials in patients aged 60 years or older, projected sample sizes were 1080 per arm for 80% power to detect a 33% relative risk reduction.

Conclusions and Relevance

The findings of this study suggest that age is a determinant of risk of ischemic stroke after cryptogenic TIA/stroke in patients with PFO, such that trials of PFO closure at older ages are justified; however, projected sample sizes are large.

Patent foramen ovale closure in the management of cryptogenic stroke: a review of current literature and guideline statements

OBJECTIVE

The management recommendations for patent foramen ovale (PFO) closure in cryptogenic stroke are rapidly evolving. The data has expanded recently with four major trials demonstrating superiority of percutaneous device closure over medical management in preventing cryptogenic stroke recurrence. This paper aims to review the current literature for referring physicians who may encounter patients with patent foramen ovale before referring these patients to stroke specialists and/or interventional cardiologists.

METHOD

For this Narrative review, we conducted a broad literature search with expert selection of relevant data. Our search included a review of the currently available trials, guideline statements, position papers, cost-effectiveness of device closure data, as well as the impact of device closure on quality of life.

RESULTS

Most European societies are now in favor of evaluating all patients aged 60 years or younger with recent cryptogenic stroke in the setting of a PFO after careful consideration of the patient's echocardiographic and clinical risk factors. On the other hand, American societies, except for the American Academy of Neurology, have not yet passed official updated recommendations.

CONCLUSION

PFO closure can be considered for the prevention of recurrent cryptogenic stroke in patients aged ≤60 years after a thorough evaluation and discussion about benefits and potential risks (including but not limited to atrial fibrillation) of the procedure. Accumulating evidence supports prognostic, quality of life, and economic benefit from percutaneous PFO closure with newer generation closure devices in the right subset of patients.

HIGHLIGHTS

Data from 4 major trials (RESPECT, CLOSE, DEFENSE-PFO, REDUCE) demonstrates the superiority of PFO closure over medical management alone in preventing cryptogenic stroke recurrence. Trials investigated mostly patients ≤60 years old, and therefore results may not be generalizable to the entire population. Further randomized trials evaluating the safety and efficacy of PFO closure in patients older than 60 years are warranted.Atrial fibrillation is one of the most common "occult" causes of cryptogenic stroke and should be excluded by ambulatory electrocardiographic monitoring. It is important to also rule out other causes of stroke, including hypercoagulable states, atherosclerotic lesions, other cardioembolic sources, and arterial dissection.Complications of PFO procedure include new-onset AF, development of scar tissue, risk of aortic root dilation and subsequent erosions, and potential thrombi formation on the device.PFO closure with medical therapy is more cost-effective than medical therapy alone.Patients who underwent PFO closure had lower rates of depression, anxiety, and stress compared to those who did undergo closure.Development of the RoPE score has helped clinicians identify patients with cryptogenic stroke and PFO who might be a candidate for PFO closure. A score of 7, 8, and 9-10 corresponds to a causal risk of 72%, 84%, and 88%, respectively, and defines a subset of patients who may benefit from PFO closure.Current guidelines recommend determining the need for PFO closure on a case-by-case basis, depending on risk factors, in patients age 60 or less with recent cryptogenic stroke in the setting of PFO.

Ischemic Infarction in Young Adults: A Review for Radiologists

Ischemic strokes in young adults are devastatingly debilitating and increasingly frequent. Stroke remains the leading cause of serious disability in the United States. The consequences of this familiar disease in this atypical age group are especially detrimental and long lasting. Ischemic stroke in young adults is now emerging as a public health issue, one in which radiologists can play a key role. The incidence of ischemic infarction in young adults has risen over the past couple of decades. Increased public awareness, increased use of MRI and angiography, and more accurate diagnosis may in part explain the increased detection of stroke in young adults. The increased prevalence of stroke risk factors in young adults (especially sedentary lifestyle and hypertension) may also contribute. However, compared with older adults, young adults have fewer ischemic infarcts related to the standard cardiovascular risk factors and large- or small-vessel disease. Instead, their infarcts most commonly result from cardioembolic disease and other demonstrated causes (ie, dissection). Thus, radiologists must expand their differential diagnoses to appropriately diagnose ischemic strokes and identify their causes in the young adult population. From the more frequent cardioembolism and dissection to the less common vasculitis, drug-related, CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), moyamoya, and hypercoagulable state-related infarcts, this article covers a wide breadth of causes and imaging findings of ischemic stroke in young adults. ^©RSNA, 2019.

Patent Foramen Ovale: Pivotal Role of Transesophageal Echocardiography in the Indications for Closure, Assessment of Varying Anatomies and Post-procedure Follow-up

Patent foramen ovale (PFO) is present in 15%-30% of the general population and has been associated with various pathologic states, including cryptogenic stroke, platypnea-orthodeoxia syndrome, decompression sickness and migraine with auras. Transesophageal echocardiography (TEE) has a major role in the diagnostic evaluation of PFO, as well as in the post-procedural assessment after transcatheter closure. The goals of this article were to synthesize the echocardiographic transesophageal techniques required for accurate PFO diagnosis and careful anatomic assessment of its anatomic variants, to focus TEE indications for device closure as complementary to clinical indications and to assess the role of TEE in the post-procedure follow-up.

Device Closure of Patent Foramen Ovale for Cryptogenic Stroke: Patient Selection and Outcomes According to New Randomized Trials

PURPOSE OF REVIEW

This review summarizes the most recent randomized clinical trials that studied the role of device-mediated patent foramen ovale (PFO) closure in patients after an ischemic stroke presumed to have been caused by a paradoxical embolism.

RECENT FINDINGS

Three major randomized trials published in 2017 studied the strategy of using PFO closure for secondary prevention in patients between the ages of 18 and 60 who presented with an index stroke having characteristics of an embolic mechanism. All patients had a PFO that potentially could have enabled paradoxical embolism and other causes of stroke were excluded by a thorough neurologic and cardiac evaluation. Patients were randomized to PFO closure versus medical therapy alone using a variety of guideline-recommended medications. After multiple years of follow-up, all three trials showed superiority in the device arm versus the medical arm with a relative risk reduction of recurrent stroke from 46 to 100% and an absolute recurrent stroke reduction from 0.49 to 1.32% per year. Complications related to the procedure and the device were infrequent and mostly transient. These results have transformed the care of these patients, lead to FDA approval of two PFO closure devices, and started the process of updating guidelines. Patient selection is critically important since the presence of a PFO may be incidental. Therefore, both a neurologist and a cardiologist, who can also perform this procedure safely and effectively, should complete the initial evaluation and discuss their findings and recommendations with the patient as part of a shared decision-making process. There are remaining questions regarding how these trial results relate to older patients, patients with overt venothrombotic disease, and those with thrombophilia.