Transcatheter Closure of Patent Foramen Ovale versus Medical Therapy after Cryptogenic Stroke: A Meta-Analysis of Randomized Controlled Trials

A matching-adjusted indirect comparison of results from REDUCE and RESPECT-two randomized trials on patent foramen ovale closure devices to prevent recurrent cryptogenic stroke

AIMS

Two randomized clinical trials, REDUCE and RESPECT, demonstrated that patent foramen ovale (PFO) closure in combination with antithrombotic therapy was more effective for the prevention of recurrent ischemic stroke compared with antithrombotic therapy alone. The aim of this study was to determine the relative efficacy and safety of the PFO closure devices used in REDUCE (HELEX and CARDIOFORM Septal Occluders) compared with the device used in RESPECT (Amplatzer PFO Occluder).

METHODS

An unanchored matching-adjusted indirect comparison (MAIC) of the PFO closure arms of the REDUCE and RESPECT trials was performed using patient-level data from REDUCE weighted to match baseline characteristics from RESPECT. Comparisons of the following outcomes were made between the devices assessed in the trials: risk of recurrent ischemic stroke; recurrent ischemic stroke one year after randomization; any serious adverse event (SAE) related to the procedure or device; and atrial fibrillation or atrial flutter as an SAE related to the procedure or device.

RESULTS

After conducting the MAIC, baseline characteristics were well-matched between the two trials. Compared to RESPECT, PFO closure using the devices from REDUCE resulted in a hazard ratio of 0.46 (95% confidence interval [CI] 0.15-1.43; p = 0.17) for the risk of recurrent stroke. For the recurrence of stroke after one year, SAE related to the procedure or device, and atrial fibrillation or atrial flutter as SAE related to the procedure or device, the MAIC resulted in a rate difference of -0.68 (95%CI -2.06 to 0.70; p = .34), -1.29 (95%CI -3.82 to 1.25; p = .32), and -0.19 (95%CI -1.16 to 0.78; p = .71), respectively. These findings were consistent across scenario analyses.

CONCLUSIONS

This MAIC analysis found no statistically significant differences in efficacy and safety outcomes between PFO closure with the HELEX and CARDIOFORM Septal Occluders versus the Amplatzer PFO Occluder, as used in the REDUCE and RESPECT trials.

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.

Patent foramen ovale-When to close and how?

Closure of a patent foramen ovale (PFO) in patients after cryptogenic/cardioembolic stroke is recommended by current guidelines for patients who are 16-60 years of age with a high-risk PFO (class of recommendation A, level of evidence I). The use of double-disk occlusion devices followed by antiplatelet therapy is recommended. The procedure of interventional PFO closure compared with other interventions in cardiology is rather easy to learn. However, it should be performed carefully to avoid postinterventional complications. The number needed to treat (NNT) to avoid one stroke in 5 years in the RESPECT trial was 42, in the CLOSE trial even lower with 20. In the REDUCE trial, the NNT was 28 at 2 years. This can be reduced by longer follow-up, e.g., at 10 years the NNT is 18. While other conditions such as migraine are currently under investigation with respect to the impact of PFO closure, sufficiently powered trials are lacking so that closure in diseases other than stroke should always be individualized.

The role of cardiologists on the stroke unit

Cardiologists need a better understanding of stroke and of cardiac implications in modern stroke management. Stroke is a leading disease in terms of mortality and disability in our society. Up to half of ischaemic strokes are directly related to cardiac and large artery diseases and cardiovascular risk factors are involved in most other strokes. Moreover, in an acute stroke direct central brain signals and a consecutive autonomic/vegetative imbalance may account for severe and life-threatening cardiovascular complications. The strong cerebro-cardiac link in acute stroke has recently been addressed as the stroke-heart syndrome that requires careful cardiovascular monitoring and immediate therapeutic measures. The regular involvement of cardiologic expertise in daily work on a stroke unit is therefore of high importance and a cornerstone of up-to-date comprehensive stroke care concepts. The main targets of the cardiologists' contribution to acute stroke care can be categorized in three main areas (i) diagnostics workup of stroke aetiology, (ii) treatment and prevention of complications, and (iii) secondary prevention and sub-acute workup of cardiovascular comorbidity. All three aspects are by themselves highly relevant to support optimal acute management and to improve the short-term and long-term outcomes of patients. In this article, an overview is provided on these main targets of cardiologists' contribution to acute stroke management.

Patent Foramen Ovale Closure: State of the Art

Patent foramen ovale (PFO) is a common abnormality affecting between 20% and 34% of the adult population. For most people, it is a benign finding; however, in some people, the PFO can open widely to enable paradoxical embolus to transit from the venous to arterial circulation, which is associated with stroke and systemic embolisation. Percutaneous closure of the PFO in patients with cryptogenic stroke has been undertaken for a number of years, and a number of purpose-specific septal occluders have been marketed. Recent randomised control trials have demonstrated that closure of PFO in patients with cryptogenic stroke is associated with reduced rates of recurrent stroke. After a brief overview of the anatomy of a PFO, this article considers the evidence for PFO closure in cryptogenic stroke. The article also addresses other potential indications for closure, including systemic arterial embolisation, decompression sickness, platypnoea-orthodeoxia syndrome and migraine with aura. The article lays out the pre-procedural investigations and preparation for the procedure. Finally, the article gives an overview of the procedure itself, including discussion of closure devices.

Updates in the Management of Cryptogenic Stroke and Patent Foramen Ovale

BACKGROUND

Stroke is a common neurological disorder and may present with visual symptoms. A thorough workup is warranted to determine the underlying cause of stroke to optimize secondary prevention. Despite a full workup, a high-risk mechanism may not be identified. Optimal treatment in this patient population has been the subject of recent research, particularly with regard to low-risk stroke mechanisms such as patent foramen ovale (PFO).

EVIDENCE ACQUISITION

Using PubMed and published stroke guidelines, an evidence-based literature review was performed.

RESULTS

In this review, we compare cryptogenic stroke with the newer concept of embolic stroke of undetermined source, summarize the most common causes presumed to underlie these strokes, and review the evidence for optimal antithrombotic management. We also review recent clinical trials demonstrating a benefit for percutaneous closure of PFO for secondary stroke prevention in select patients.

CONCLUSIONS

Stroke management is based on evaluation of individual patient-risk factors. Evaluation and treatment is ideally directed by a vascular neurologist to ensure optimal secondary prevention, especially in cases where an underlying etiology is not identified on initial workup.

Recurrent Stroke Reduction with Patent Foramen Ovale Closure versus Medical Therapy Based on Patent Foramen Ovale Characteristics: A Meta-Analysis of Randomized Controlled Trials

Efficacy of patent foramen ovale (PFO) closure in patients with cryptogenic stroke remains a matter of debate. We performed a comprehensive meta-analysis of available randomized controlled trials (RCTs) to evaluate the efficacy and safety of PFO closure versus medical therapy (MT) based on PFO characteristics. Random-effects meta-analysis was conducted to estimate risk ratio (RR) with 95% confidence intervals (CI) for the primary end points of stroke. After systematic search, six RCTs (3,747 patients) with 1,889 patients randomized to PFO closure and 1,858 patients randomized to the MT group were included in the meta-analysis. Overall, PFO closure was associated with a significant reduction in recurrent stroke compared to MT [RR 0.41; 95% CI 0.20-0.83]. While there were no differences in mortality or major bleeding between the two groups, risk of newly diagnosed atrial fibrillation was higher in the PFO closure group compared to MT [RR 5.29; 95% CI 2.32-12.06]. Further, risk reduction in stroke with PFO closure was significant in patients with high-risk PFO characteristics [RR 0.37; 95% CI 0.16-0.87] but not in low-risk patients [RR 0.73; 95% CI 0.29-1.84]. In conclusion, among patients with cryptogenic stroke, PFO closure is associated with a significantly reduced risk of recurrent stroke compared to MT. Additionally, the benefit of PFO closure might be dependent on certain PFO characteristics.

Closing the gap on patent foramen ovale and cryptogenic stroke

Introduction: The treatment options for prevention of recurrent of cryptogenic stroke in patients with patent foramen ovale (PFO) have been intensely debated in the recent decades. The suggested options were percutaneous closure of PFO versus medical therapy. However, up to these date there is a controversy regarding the indication of percutaneous closure. Multiple meta-analysis and recent randomized control trials showed the benefit of PFO closure when compared with medical therapy alone. Areas covered: The article reviews the prevalence, physiology, diagnosis and treatment options of PFO after cryptogenic stroke. Furthermore, it will discuss the results of randomized control trials that compared the PFO closure to medical therapy. Expert opinion: The association between PFO and unexplained cryptogenic stroke has been well established in the multiple studies. The diagnosis and management of PFO might be challenging in some cases. Although multiple studies showed that PFO closure is associated with lower rates of recurrent stroke in patients presenting with cryptogenic stroke, the indication and patient selection for this intervention are not well established yet in the guidelines.

Long-term safety and efficacy of combined percutaneous LAA and PFO/ASD closure: a single-center experience (LAAC combined PFO/ASD closure)

OBJECTIVES

To report long-term safety and efficacy of combined percutaneous LAA and PFO/ASD closure.

METHODS

A retrospective study of 370 consecutive patients undergoing LAAC procedures using the Watchman (WM) device. Data were compared between 330 cases only with LAAC procedure (Group I) and 25/5 (PFO/ASD) cases with sequential procedures of LAAC and PFO/ASD closure (Group II).

RESULTS

Compared to Group I, Group II had more males (86.7% vs. 65.8%, p < 0.05) and a higher rate of stroke (33.3% vs. 10.6%, p < 0.01), but there were no statistical differences in the remaining patient characteristics. During the follow-up period, there were no significant differences between the two groups in embolism events (6.1% vs. 0%, p = 0.39), device related thrombus (5.8% vs 3.3%, p = 1.0), major bleeding (9.4% vs. 6.7%, p = 1.0) and cardiac death (3.6% vs. 0%, p = 0.61). The observed rate of all thromboembolic events by Kaplan-Meier analysis was decreased by 39.9% and 100% and the observed annual rate of bleeding was reduced by 32.9% and 57.6% in Group I and Group II, respectively.

CONCLUSIONS

LAAC combined with PFO/ASD closure might be an ideal choice to prevent stroke and other thrombotic complications in patients with both NVAF and PFO/ASD.

Patent Foramen Ovale Closure in 2019

Patent foramen ovale (PFO) is a common abnormality affecting between 20% and 34% of the adult population. For most people it is a benign finding; however, in some the PFO can open widely, enabling a paradoxical embolus to transit from the venous to arterial circulation, which is associated with stroke and systemic embolisation. Percutaneous closure of PFO in patients with cryptogenic stroke has been undertaken for a number of years, and a number of purpose-specific septal occluders have been marketed. Recent randomised controlled trials have demonstrated that closure of PFO in patients with cryptogenic stroke is associated with reduced rates of recurrent stroke. After a brief overview of the anatomy of a PFO, this review considers the evidence for PFO closure in cryptogenic stroke. The review also addresses other potential indications for closure, including systemic embolisation, decompression sickness, platypnoea-orthodeoxia syndrome and migraine with aura. It lays out the pre-procedural investigations and preparation for the procedure. Finally, it gives an overview of the procedure itself, including discussion of closure devices.

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.

Patent Foramen Ovale Closure Versus Medical Therapy in Cryptogenic Strokes and Transient Ischemic Attacks: A Meta-Analysis of Randomized Trials

Cryptogenic strokes account for about 25% to 40% of total ischemic strokes, and 1 of the 3 of these have a patent foramen ovale (PFO). A meta-analysis concerning the effectiveness and safety of PFO closure in cryptogenic strokes or transient ischemic attacks (TIAs) was performed. We systematically searched Medline, Embase, and the Cochrane Library through April 2018. Eligible studies were randomized clinical trials. Primary and secondary end points were, respectively, stroke or TIA and stroke recurrences. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) for all end points using fixed- and random-effects meta-analyses. Data were included from 6 trials involving 3560 patients. In the pooled analysis, PFO closure was superior to medical treatment for both primary (RR: 0.39; 95% CI: 0.18-0.82; P < .02) and secondary end points (RR: 0.58; 95% CI: 0.44-0.76; P < .001). Transcatheter closure significantly increased the risk of new-onset atrial fibrillation (AF; RR: 5.74; P < .001). Percutaneous closure is superior to medical treatment in reducing stroke and TIA recurrence, even if with a significant risk increasing for new-onset AF. These findings suggest that transcatheter closure is indicated in patients with cryptogenic strokes and large PFO.