Stroke Recurrence and its Prevention in Patients with Patent Foramen Ovale

Real-world evidence in health technology assessment of high-risk medical devices: Fit for purpose?

Health technology assessment (HTA) of medical devices (MDs) increasingly rely on real-world evidence (RWE). The aim of this study was to evaluate the type and the quality of the evidence used to assess the (cost-)effectiveness of high risk MDs (Class III) by HTA agencies in Europe (four European HTA agencies and EUnetHTA), with particular focus on RWE. Data were extracted from HTA reports on the type of evidence demonstrating (cost-)effectiveness, and the quality of observational studies of comparative effectiveness using the Good Research for Comparative Effectiveness principles. 25 HTA reports were included that incorporated 28 observational studies of comparative effectiveness. Half of the studies (46%) took important confounding and/or effect modifying variables into account in the design and/or analyses. The most common way of including confounders and/or effect modifiers was through multivariable regression analysis. Other methods, such as propensity score matching, were rarely employed. Furthermore, meaningful analyses to test key assumptions were largely omitted. Resulting recommendations from HTA agencies on MDs is therefore (partially) based on evidence which is riddled with uncertainty. Considering the increasing importance of RWE it is important that the quality of observational studies of comparative effectiveness are systematically assessed when used in decision-making.

Meta-analysis of patent foramen ovale closure versus medical therapy for prevention of recurrent ischemic neurological events: Impact of medication type

BACKGROUND

The optimal treatment strategy for patent foramen ovale (PFO) patients with cryptic stroke remains controversial. We performed this meta-analysis to evaluate the effect of PFO closure versus different types of medical therapy.

METHODS

We searched PubMed, Embase, and Cochrane databases. The primary efficacy endpoints were the composite outcome of recurrent stroke and/or transient ischemic attack (TIA). Secondary efficacy endpoints included separate stroke and TIA. Safety endpoints included new-onset atrial fibrillation (AF)/atrial flutter and bleeding.

RESULTS

Compared with antiplatelet therapy, PFO closure significantly reduced the risk of composite outcome (odds ratio [OR] 0.37, 95% confidence interval [CI] 0.27-0.51), stroke (OR 0.22, 95% CI 0.13-0.36], and TIA (OR 0.57, 95% CI 0.34-0.98); Compared with the mixed medical therapy group (consist of antiplatelet therapy, anticoagulant therapy, or both), PFO closure still showed some benefits, but the effect was not as significant as that of antiplatelet therapy (composite outcome: OR 0.53, 95% CI 0.41-0.69; stroke: OR 0.48, 95% CI 0.34-0.68; TIA: OR 0.69, 95% CI 0.50-0.96); Compared with anticoagulant therapy, PFO closure showed no benefit (composite outcome: OR 0.77, 95% CI 0.46-1.28; stroke: OR 0.59, 95% CI 0.28-1.25; TIA: OR 1.01, 95% CI 0.50-2.04). In terms of safe endpoints, compared with antiplatelet therapy and anticoagulant therapy, PFO closure increased the risk of AF/atrial flutter (OR 9.56, 95% CI 2.85-32.06; OR 18.96, 95% CI 1.11-323.8, respectively) and reduced the risk of bleeding (OR 0.50, 95% CI 0.24-1.05; OR 0.13, 95% CI 0.04-0.46, respectively); compared with mixed medical therapy, PFO closure increased the risk of AF/atrial flutter (OR 4.40,95% CI 2.24-8.67), but there was no difference in bleeding (OR 0.97, 95% CI 0.56-1.68).

CONCLUSIONS

With the addition of anticoagulants, the benefit of PFO closure decreased gradually. Patient groups that adopt individualized medical therapy strategies may benefit more.

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 for patients with cryptogenic stroke: A systematic review and comprehensive meta-analysis of 5 randomized controlled trials and 14 observational studies

BACKGROUND

Previous review from randomized controlled trials (RCT) showed that patients with cryptogenic stroke may benefit from patent foramen ovale (PFO) closure. However, the findings from the systematic review were not clear when observational studies were also included.

METHODS

We searched MEDLINE, Embase, and Cochrane databases. The primary endpoints were recurrent stroke or transient ischemic attack (TIA). The secondary outcomes were all-cause death, atrial fibrillation (AF), and hemorrhagic events.

RESULTS

Five randomized trials and fourteen observational studies (6301 participants) were eligible. PFO closure was superior to medical therapy for stroke prevention risk ratios ([RR], 0.38; 95% CI, 0.24-0.60), but showed increased risk of AF (RR, 4.96; 95% CI, 2.31-10.7). There was no significant difference in TIA recurrence, death, and hemorrhagic events. Subgroup analyses showed that patients with factors such as substantial residual shunt, the presence of atrial septal aneurysm (ASA), male, and age <45 years had a lower risk of recurrent stroke when PFOs were closed.

CONCLUSIONS

In patients with cryptogenic stroke, PFO closure does appeared to be superior to medical therapy in stroke prevention, with an increased incidence of AF. Male, age <45 years, substantial residual shunt, and the history of ASA are the factors that will predict the benefit when PFO is closed.

Percutaneous closure of patent foramen ovale vs. medical treatment for patients with history of cryptogenic stroke: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Patients with history of cryptogenic stroke are more likely to have a patent foramen ovale (PFO) and should be managed with antithrombotic agents, while the alternative option is percutaneous closure of PFOs. Our aim was to perform a meta-analysis of randomized controlled trials (RCTs) comparing percutaneous closure vs. medical treatment for patients with PFO and prior cryptogenic stroke.

METHODS

Medline, Scopus and Cochrane databases were reviewed. A random-effect model meta-analysis was used and I-square was utilized to assess the heterogeneity. New ischemic stroke was defined as the primary endpoint. A sensitivity analysis was performed for Amplatzer device. Subgroup analyses were performed for different patient and PFO characteristics for the composite endpoints as defined by the included RCTs.

RESULTS

In total of 3440 patients were included in this meta-analysis. Closure devices were superior to medical therapy for prevention of recurrent ischemic strokes (HR = 0.29; CI: 0.02-0.56), but were associated with increased risk of new onset of atrial fibrillation (AF) and atrial flutter (RR = 4.67; CI: 2.22-9.81). However, in the sensitivity analysis for Amplatzer device, there was no difference between the two groups in new onset of atrial arrhythmias. Closure devices were superior across all different subgroups when compared to medical treatment with the exception of patients with a small shunt.

CONCLUSION

This meta-analysis shows that closure devices for patients with PFO and history of cryptogenic stroke can significantly decrease the risk of a new ischemic stroke. The use of Amplatzer device was not associated with increased risk of newly diagnosed atrial arrhythmias.

Percutaneous closure versus medical therapy for stroke with patent foramen Ovale: a systematic review and meta-analysis

BACKGROUND

Patent foramen ovale (PFO) closure has emerged as a secondary prevention option in patients with PFO and cryptogenic stroke. However, the comparative efficacy and safety of percutaneous closure and medical therapy in patients with cryptogenic stroke and PFO remain unclear.

METHODS

Randomized controlled trials (RCTs) and comparative observational studies that compared PFO closure against medical therapy, each with a minimal of 20 patients in the closure arm and 1-year follow-up were included.

RESULTS

We analyzed 6961 patients from 20 studies (5 RCTs and 15 observational studies) with a median follow-up of 3.1 years. Moderate-quality evidence showed that PFO closure was associated with a significantly lower incidence of the composite outcome of ischemic stroke, transient ischemic attack (TIA), or all-cause death (odds ratio [OR]: 0.57; 95% confidence interval [CI]: 0.38 to 0.85; P = 0.006), mainly driven by lower incidence of stroke (OR: 0.39; 95% CI: 0.24 to 0.63; P < 0.001). The numbers needed to treat were 43 and 39 for the composite outcome and recurrent ischemic stroke respectively. PFO closure increased the risks for atrial fibrillation or atrial flutter (OR: 5.74; 95% CI: 3.08 to 10.70; P < 0.001; high-quality evidence) and pulmonary embolism (OR: 3.03; 95% CI: 1.06 to 8.63; P = 0.038; moderate-quality evidence), with the numbers needed to harm being 30 and 143 respectively. The risks for TIA, all-cause death, and major bleeding were not statistically different. Analyses limited to RCTs showed similar findings, as did a series of other subgroup analyses.

CONCLUSION

In conclusion, PFO closure reduced the incidences of stroke and the composite outcome of ischemic stroke, TIA, or all-cause death, but increased risks for atrial fibrillation or atrial flutter and pulmonary embolism compared with medical therapy.

Anticoagulant vs. antiplatelet therapy in patients with cryptogenic stroke and patent foramen ovale: an individual participant data meta-analysis

AIMS

The preferred antithrombotic strategy for secondary prevention in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO) is unknown. We pooled multiple observational studies and used propensity score-based methods to estimate the comparative effectiveness of oral anticoagulation (OAC) compared with antiplatelet therapy (APT).

METHODS AND RESULTS

Individual participant data from 12 databases of medically treated patients with CS and PFO were analysed with Cox regression models, to estimate database-specific hazard ratios (HRs) comparing OAC with APT, for both the primary composite outcome [recurrent stroke, transient ischaemic attack (TIA), or death] and stroke alone. Propensity scores were applied via inverse probability of treatment weighting to control for confounding. We synthesized database-specific HRs using random-effects meta-analysis models. This analysis included 2385 (OAC = 804 and APT = 1581) patients with 227 composite endpoints (stroke/TIA/death). The difference between OAC and APT was not statistically significant for the primary composite outcome [adjusted HR = 0.76, 95% confidence interval (CI) 0.52-1.12] or for the secondary outcome of stroke alone (adjusted HR = 0.75, 95% CI 0.44-1.27). Results were consistent in analyses applying alternative weighting schemes, with the exception that OAC had a statistically significant beneficial effect on the composite outcome in analyses standardized to the patient population who actually received APT (adjusted HR = 0.64, 95% CI 0.42-0.99). Subgroup analyses did not detect statistically significant heterogeneity of treatment effects across clinically important patient groups.

CONCLUSION

We did not find a statistically significant difference comparing OAC with APT; our results justify randomized trials comparing different antithrombotic approaches in these patients.

PFO Closure for Cryptogenic Stroke

A patent foramen ovale (PFO) is a common finding in the general population and has been theorized to be a mechanism for ischemic stroke primarily due to a deep venous thrombus embolizing through the shunt into the arterial circulation. There has been much debate regarding the association between PFO and stroke, especially in the case of a cryptogenic stroke (i.e., stroke of unknown etiology) in a younger patient without other risk factors. Traditionally, when a PFO is detected, antithrombotic therapy to mitigate risk of a future ischemic event has been the mainstay of treatment. More recently, both surgical and transcatheter closure of a PFO have been widely utilized. However, there are only few randomized controlled trials assessing the efficacy of PFO closure for stroke prevention.

Meta-analysis of net long-term benefit of different therapeutic strategies in patients with cryptogenic stroke and patent foramen ovale

We pooled available data on follow-up events in patients with patent foramen ovale and cryptogenic stroke to evaluate the net clinical benefit of different therapeutic strategies (percutaneous closure vs antiplatelet vs anticoagulant therapy). MEDLINE/PubMed and Cochrane databases and reviewed cited references to identify relevant studies were used; 3,311 patients from 21 clinical studies, both observational and randomized, with follow-up ≥12 months were overall included. Net clinical benefit was evaluated considering the cumulative incidence of both stroke and/or transient ischemic attack and major bleeding events. Anticoagulant therapy was more effective than antiplatelet therapy in preventing recurrent stroke and/or transient ischemic attack (event rates: 7.7% vs 9.8%, respectively, p = 0.03), but at the price of more than sixfold greater risk of major bleeding (7.1% vs 1.3%; odds ratio 6.49, 95% confidence interval 3.25 to 12.99, p <0.00001). Patent foramen ovale closure was associated over the long term with significant net clinical benefit versus both antiplatelet and anticoagulant therapy; such benefit was driven by 50% relative reduction of stroke and/or transient ischemic attack versus antiplatelet therapy and by 82% relative reduction of major bleeding versus anticoagulant therapy. In conclusion, results of this large study-level meta-analysis may influence practice patterns in patients with patent foramen ovale and cryptogenic stroke; an individualized approach tailored on both the risk of recurrent cerebral events and the bleeding risk should be used to identify the best therapeutic option (percutaneous closure vs antiplatelet therapy vs anticoagulant therapy).

Recurrent Stroke/TIA in Cryptogenic Stroke Patients with Patent Foramen Ovale

Background:

Patent foramen ovale (PFO) is present in 40% of patients with cryptogenic stroke and may be associated with paradoxical emboli to the brain. Therapeutic options include antiplatelet agents, anticoagulation, percutaneous device and surgical closure. We assessed the hypothesis that there are differences in rates of recurrent TIA or stroke between patients in the four treatment groups.

Methods:

Patients presenting from January 1997 with cryptogenic stroke or TIA and PFO were followed prospectively until June 2003. Treatment choice was made on an individual case basis. The primary outcome was recurrent stroke. The secondary outcome was a composite of stroke, TIA, and vascular death.

Results:

Baseline. Our cohort consisted of 121 patients; 64 (53%) were men. Median age was 43 years. Sixty-nine percent presented with stroke and 31% with TIA. One or more vascular risk factor was present in 40%. Atrial septal aneurysm (ASA) was present in 24%. Treatment consisted of antiplatelet agents (34%), anticoagulation (17%), device (39%) and surgical closure (11%). Follow-up. Recurrent events occurred in 16 patients (9 antiplatelet, 3 anticoagulation, 4 device closure); 7 were strokes, 9 were TIA. Comparing individual treatments there was a trend toward more strokes in the antiplatelet arm (p=0.072); a significant difference was seen for the composite endpoint (p=0.012). Comparing closure versus combined medical therapy groups, a significant difference was seen for primary (p=0.014) and secondary (p=0.008) outcomes, favoring closure. Age and pre-study event predicted outcome.

Conclusion:

Patent foramen ovale closure was associated with fewer recurrent events. Complications of surgical and device closure were self-limited.

Ischaemic stroke with patent foramen ovale

BACKGROUND

There is no sound scientific documentation of current guidelines for the treatment of cerebral infarction assumed to be due to patent foramen ovale. In this article, we present a young patient with this condition. In addition, we provide a general overview of the prevalence, recommended assessment and indications for treatment of patent foramen ovale in ischaemic stroke patients.

METHOD

The article is based on a non-systematic search in PubMed. We emphasise three recently published randomised trials on the subject.

RESULTS

Transoesophageal echocardiography with saline contrast is the gold standard for detecting patent foramen ovale. Just who will benefit from the diagnosis and treatment of this condition remains unclear, however. None of the three randomised studies of antithrombotic treatment versus transcatheter closure in patients who have suffered ischaemic stroke show a difference in outcomes, but subgroup analyses indicate that closure in young patients (age <50 years) with a large foramen ovale reduces the number of recurrent ischaemic events. Two other randomised studies of antithrombotic treatment alone versus closure are presently ongoing.

INTERPRETATION

For stroke patients with patent foramen ovale, the choice between lifelong antithrombotic therapy alone and transcatheter closure is a difficult one. Treatment with antiplatelet agents remains the first choice in most cases. Well-designed studies are needed to identify which patients will benefit most from closure.

Implantable devices for the closure of patent foramen ovale in adults: an Italian rapid health technology assessment

Percutaneous closure of patent foramen ovale (PFO) is offered to patients suffering from cryptogenic stroke, transient ischemic attack or persistent migraine. Several PFO closure devices are CE marked but none have yet been approved by the FDA. On the Italian market 11 different PFO closure devices are available and more than 2500 PFO procedures were reported in 2012. We report findings of a systematic review and meta-analysis of studies in which patients with PFO and transient ischemic attacks, cryptogenic stroke or persistent migraine who underwent PFO closure were compared to patients treated by usual care. We included five controlled clinical trials and one randomized controlled trial. Included studies had poor methodological quality and heterogeneity. In the included randomized controlled trial, 4.7% of procedure-related serious adverse events were observed. Large multicenter, sufficiently powered, and properly randomized trials need to be conducted in Europe with particular attention to patient selection.

Seven-year follow-up of percutaneous closure of patent foramen ovale

Background

Observational studies favor percutaneous closure of patent foramen ovale (PFO) over medical treatment to reduce recurrent stroke while randomized trials fail to demonstrate significant superiority of percutaneous PFO closure. Few long-term studies are available post PFO closure. This study reports long-term clinical outcomes after percutaneous PFO closure.

Methods

Between 1997 and 2006, 86 consecutive eligible patients with cerebrovascular events, presumably related to PFO, underwent percutaneous PFO closure. All 86 patients were invited to a long-term follow-up, which was carried out during 2011 and 2012.

Results

Percutaneous PFO closure was successfully performed in 85 of 86 patients. The follow-up rate was 100%. No cardiovascular or cerebrovascular deaths occurred. Two patients (both women) died from lung cancer during follow-up. Follow-up visits were conducted for 64 patients and the remaining 20 patients were followed up by phone. The mean follow-up time was 7.3 years (5 to 12.4 years). Mean age at PFO closure was 49 years. One patient had a minor stroke one month after PFO closure and a transient ischemic attack (TIA) two years afterwards. One other patient suffered from a TIA six years after closure. No long-term device-related complications were observed.

Conclusions

Percutaneous PFO closure was associated with very low risk of recurrent stroke and is suitable in most patients. We observed no mortality and no long-term device-related complications related to PFO closure, indicating that percutaneous PFO closure is a safe and efficient treatment even in the long term.

Multidisciplinary management of patent foramen ovale (PFO) and cryptogenic stroke/TIA

PURPOSE

Patent foramen ovale (PFO) has been implicated as a risk factor for cryptogenic ischemic stroke (CS). However, there is still a lack of widely accepted, undisputed indications for PFO closure. The present study describes the concept of the multidisciplinary PFO conference and a decision making process for closure versus no closure that was developed into a formalized clinical algorithm, and presents the results of implementing these, in terms of number and proportion of PFO closures as well as repeat referrals.

DESIGN

Five specialists in neurology, cardiology, internal medicine, thromboembolism, and echocardiography evaluated the clinical data of 311 patients at PFO conferences during 2006 to 2009. The main criteria for closure were patients with first-ever CS with PFO and atrial septal aneurysm, or patients with recurrent CS and PFO without atrial septal aneurysm.

RESULTS

A total of 143 patients (46%) were accepted for closure and 167 patients were rejected. Patients accepted for closure were younger (mean 50 years versus 58 years) (P < 0.001). The acceptance rate for PFO closure was similar throughout these years, with an average of 45%. Three of 167 patients (1.8%) initially rejected for PFO closure were re-referred due to recurrent stroke, and the PFO closure was subsequently performed.

CONCLUSION

The acceptance rate of less than 50% in the present study underscores the complex relationship between CS and PFO. Whatever the criteria used for PFO closure, any unit caring for these patients needs to have a rigorous process to avoid overtreatment as well as undertreatment and to ensure that personal preferences and economic incentives do not steer the selection process. Our algorithm provides a stable acceptance rate and a low rate of repeat referrals.

Shunt volume dynamics in stroke patients with patent foramen ovale

A variation in right atrial and pulmonary arterial pressure might result in a shunt dynamic across a patent foramen ovale (PFO). In the present study we tested if peak exercise facilitates a restoration of right to left shunt (RLS) in stroke patients who demonstrated a functional PFO closure (no evidence of RLS across an initially demonstrated PFO). In stroke patients with PFO demonstrating a functional closure, the RLS was reassessed on peak exercise using contrast-enhanced transcranial Doppler sonography. The exercise procedure consisted of a cardiopulmonary exercise test with supplementary stress echocardiography for assessment of pulmonary circulation. Four stroke patients with initially PFO curtain pattern and a subsequent functional PFO closure (no evidence for RLS) underwent the procedure. In all four patients a RLS could be resurrected during peak physical exercise after a Valsalva strain. While in two patients peak exercise led to an RLS in a countable range of microembolic signals, in two patients a curtain pattern was obtained. One patient showed evidence for reoccurrence of RLS on peak exercise without a Valsalva strain. The patients with curtain pattern had a better peak exercise performance. Although the systolic pulmonary arterial pressure increased during exercise in all patients, there was no direct correlation with the detected RLS. After a functional PFO closure peak exercise combined with a Valsalva strain facilitates the reoccurrence of RLS in stroke patients.

Meta-analysis of transcatheter closure versus medical therapy for patent foramen ovale in prevention of recurrent neurological events after presumed paradoxical embolism

OBJECTIVES

In this study, a meta-analysis of observational studies was performed to compare the rate of recurrent neurological events (RNE) between transcatheter closure and medical management of patients with cryptogenic stroke/transient ischemic attack (TIA) and concomitant patent foramen ovale (PFO).

BACKGROUND

A significant controversy surrounds the optimal strategy for treatment of cryptogenic stroke/TIA and coexistent PFO.

METHODS

We conducted a MEDLINE search with standard search terms to determine eligible studies.

RESULTS

Adjusted incidence rates of RNE were 0.8 (95% confidence interval [CI]: 0.5 to 1.1) events and 5.0 (95% CI: 3.6 to 6.9) events/100 person-years (PY) in the transcatheter closure and medical management arms, respectively. Meta-analysis of the limited number of comparative studies and meta-regression analysis suggested that the transcatheter closure might be superior to the medical therapy in prevention of RNE after cryptogenic stroke. Comparison of the anticoagulation and antiplatelet therapy subgroups of the medical arm yielded a significantly lower risk of RNE within patients treated with anticoagulants. Device-related complications were encountered at the rate of 4.1 (95% CI: 3.2 to 5.0) events/100 PY, with atrial arrhythmias being the most frequent complication. After transcatheter closure, RNE did not seem to be related to the pre-treatment shunt size or the presence of residual shunting in the follow-up period. Significant benefit of transcatheter PFO closure was apparent in elderly patients, patients with concomitant atrial septal aneurysm, and patients with thrombophilia.

CONCLUSIONS

Rates of RNE with transcatheter closure and medical therapy in patients presenting with cryptogenic stroke or TIA were estimated at 0.8 and 5.0 events/100 PY. Further randomized controlled trials are needed to conclusively compare these 2 management strategies.

Patent foramen ovale closure and medical treatments for secondary stroke prevention: a systematic review of observational and randomized evidence

BACKGROUND AND PURPOSE

Patients discovered to have a patent foramen ovale in the setting of a cryptogenic stroke may be treated with percutaneous closure, antiplatelet therapy, or anticoagulants. A recent randomized trial (CLOSURE I) did not detect any benefit of closure over medical treatment alone; the optimal medical therapy is also unknown. We synthesized the available evidence on secondary stroke prevention in patients with patent foramen ovale and cryptogenic stroke.

METHODS

A MEDLINE search was performed for finding longitudinal studies investigating medical treatment or closure, meta-analysis of incidence rates (IR), and IR ratios of recurrent cerebrovascular events.

RESULTS

Fifty-two single-arm studies and 7 comparative nonrandomized studies and the CLOSURE I trial were reviewed. The summary IR of recurrent stroke was 0.36 events (95% confidence interval [CI], 0.24-0.56) per 100 person-years with closure versus 2.53 events (95% CI, 1.91-3.35) per 100 person-years with medical therapy. In comparative observational studies, closure was superior to medical therapy (IR ratio=0.19; 95% CI, 0.07-0.54). The IR for the closure arm of the CLOSURE I trial was higher than the summary estimate from observational studies; there was no significant benefit of closure over medical treatment (P=0.002 comparing efficacy estimates between observational studies and the trial). Observational and randomized data (9 studies) comparing medical therapies were consistent and suggested that anticoagulants are superior to antiplatelets for preventing stroke recurrence (IR ratio=0.42; 95% CI, 0.18-0.98).

CONCLUSIONS

Although further randomized trial data are needed to precisely determine the effects of closure on stroke recurrence, the results of CLOSURE I challenge the credibility of a substantial body of observational evidence strongly favoring mechanical closure over medical therapy.

Decrease in shunt volume in patients with cryptogenic stroke and patent foramen ovale

BACKGROUND

In patients with patent foramen ovale (PFO) there is evidence supporting the hypothesis of a change in right-to-left shunt (RLS) over time. Proven, this could have implications for the care of patients with PFO and a history of stroke. The following study addressed this hypothesis in a cohort of patients with stroke and PFO.

METHODS

The RLS volume assessed during hospitalisation for stroke (index event/T0) was compared with the RLS volume on follow-up (T1) (median time between T0 and T1 was 10 months). In 102 patients with a history of stroke and PFO the RLS volume was re-assessed on follow-up using contrast-enhanced transcranial Doppler/duplex (ce-TCD) ultrasound. A change in RLS volume was defined as a difference of ≥20 microembolic signals (MES) or no evidence of RLS during ce-TCD ultrasound on follow-up.

RESULTS

There was evidence of a marked reduction in RLS volume in 31/102 patients; in 14/31 patients a PFO was no longer detectable. An index event classified as cryptogenic stroke (P < 0.001; OD = 39.2, 95% confidence interval 6.0 to 258.2) and the time interval to the follow-up visit (P = 0.03) were independently associated with a change in RLS volume over time.

CONCLUSIONS

RLS volume across a PFO decreases over time, especially in patients with cryptogenic stroke. These may determine the development of new strategies for the management in the secondary stroke prevention.

Guidelines for the prevention of stroke in patients with stroke or transient ischemic attack: a guideline for healthcare professionals from the american heart association/american stroke association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of ischemic stroke among survivors of ischemic stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches for atherosclerotic disease, antithrombotic treatments for cardioembolism, and the use of antiplatelet agents for noncardioembolic stroke. Further recommendations are provided for the prevention of recurrent stroke in a variety of other specific circumstances, including arterial dissections; patent foramen ovale; hyperhomocysteinemia; hypercoagulable states; sickle cell disease; cerebral venous sinus thrombosis; stroke among women, particularly with regard to pregnancy and the use of postmenopausal hormones; the use of anticoagulation after cerebral hemorrhage; and special approaches to the implementation of guidelines and their use in high-risk populations.

Percutaneous PFO closure with Amplatzer PFO occluder: predictors of residual shunts at 6 months follow-up

OBJECTIVE

The objective of this study was to assess predictors of residual shunts after percutaneous patent foramen ovale (PFO) closure with Amplatzer PFO occluder (AGA Medical Corporation, Golden Valley, MN, USA).

METHODS

All percutaneous PFO closures, using Amplatzer PFO occluder performed at a tertiary center between May 2002 and August 2006, were reviewed. Follow-up, including saline contrast transesophageal echocardiography, was performed in all patients 6 months after the intervention.

PATIENTS

A total of 135 procedures were performed. Mean age of the patients was 51 years. The indication for PFO closure was an ischemic cerebrovascular event in 92%, paradoxical systemic embolism in 4%, and a diving accident in 4%. Recurrent events prior to PFO closure were noted in 34%. A concomitant atrial septal aneurysm was present in 61%.

RESULTS

At 6 months follow-up, a residual shunt was detected in 26 patients (19%). Residual shunts were more common in patients with an atrial septal aneurysm (27 vs. 8%, P= .01) and in patients treated with a 35-mm compared with a 25-mm device (39 vs. 15%, P= .01). A concomitant atrial septal aneurysm remained independently associated with residual shunts when controlled for body mass index, gender, age, atrial dimensions, and presence of a Chiari network (odds ratio 4.1, 95% confidence intervals 1.1-15.0).

CONCLUSION

The presence of atrial septal aneurysms in patients undergoing percutaneous PFO closure with an Amplatzer PFO occluder significantly increases the rate of residual shunts at 6 months follow-up, even if 35-mm devices are used.

Atrial fibrillation following device closure of patent foramen ovale

OBJECTIVES

Recurrent embolic events after device closure of patent foramen ovale (PFO) have been related to incomplete closure. Another cause could be atrial fibrillation (AF). The aim of this study was to determine the incidence of AF in stroke patients after PFO closure.

METHODS

Consecutive patients with device closure of a PFO after a stroke or transient ischemic attack and control patients with stroke underwent 7-day event loop recordings 3 and 6 months after PFO closure or stroke, respectively.

RESULTS

Forty patients treated by PFO device closure 96 +/- 68 days after cryptogenic ischemic stroke and 70 control patients with ischemic stroke of other etiologies (known AF excluded) were compared. AF was identified in 6 patients (15%) of the treated group and in 12 control patients (17%, p = 0.77). In multivariate analysis, the presence of an occluder device was not an independent risk factor for AF.

CONCLUSIONS

The incidence of AF is high after device closure of a PFO in stroke patients and similar to that in patients with stroke of non-PFO etiology and, hence, with no device. Further studies are required to determine the risk of thromboembolism and the optimal treatment in patients developing AF after device closure of a PFO.