Enhanced thrombogenesis but not platelet activation is associated with transcatheter closure of patent foramen ovale in patients with cryptogenic stroke

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.

Right disc thrombosis of the new Gore Cardioform ASD Occluder

BACKGROUND

The GCA is a well performing device in terms of efficacy despite complex anatomies (aortic rim <5 mm and ASD diameter >17 mm) with a good safety profile.

AIMS

To evaluate atrial septal defect (ASD) features impacting on right disc device thrombosis in patients who underwent Gore Cardioform ASD Occluder (GCA) implantation.

METHODS

A total of 44 consecutive patients undergoing percutaneous ASD with GCA device from January 2020 to September 2022 at our tertiary care Center were evaluated. The minimum follow-up was 6 months.

RESULTS

The patients were stratified in two groups according to a cut-off value of ASD diameter equal to 20 mm at sizing balloon, derived from ROC analysis (AUC = 0.894; p = 0.024). Baseline characteristics were comparable between groups in terms of age, sex, weight, height, and interatrial septum dimensions. Patients with ASD > 20 mm (n = 9) had a higher ASD/device dimension ratio, both at echocardiography (p = 0.009) and at sizing balloon (p = 0.001), longer fluoroscopic time (p = 0.022), and higher incidence of device thrombosis (0.006). Right disc thrombosis was observed in three patients of the ASD > 20 mm group, always in the inferior portion of the right disc. On univariate analysis, ASD diameter at sizing balloon (OR 1.360; p = 0.036) was the only positive predictor of device thrombosis.

CONCLUSIONS

Right disc thrombosis of the GCA device may be under-recognized at follow-up, hence deserving clinical attention, especially in those patients with larger ASD diameters.

Impact of the antiplatelet strategy following patent foramen ovale percutaneous closure

AIMS

Temporary dual antiplatelet therapy (DAPT) is recommended following patent foramen ovale (PFO) percutaneous closure although its benefit, compared to single antiplatelet therapy (SAPT), has not been demonstrated in this setting. We aimed at assessing outcomes following PFO closure according to the antiplatelet strategy at discharge.

METHODS AND RESULTS

The ambispective AIR-FORCE cohort included consecutive patients from seven centres in France and Canada undergoing PFO closure and discharged without anticoagulation. Patients treated in French and Canadian centres were mostly discharged with DAPT and SAPT, respectively. The primary endpoint was the composite of death, stroke, transient ischaemic attack, peripheral embolism, myocardial infarction, or BARC type ≥2 bleeding with up to 5 years of follow-up. The impact of the antiplatelet strategy on outcomes was evaluated with a marginal Cox model (cluster analyses per country) with inverse probability weighting according to propensity score. A total of 1532 patients (42.2% female, median age: 49 [40-57] years) were included from 2001 to 2022, of whom 599 (39.1%) were discharged with SAPT and 933 (60.9%) with DAPT, for ≤3 months in 894/923 (96.9%) cases. After a median follow-up of 2.4 [1.1-4.4] years, a total of 58 events were observed. In the weighted analysis, the rate of the primary endpoint up to 5 years was 7.8% in the SAPT strategy and 7.3% in the DAPT strategy (weighted hazard ratio 1.04, 95% confidence interval 0.59-1.83).

CONCLUSION

The antiplatelet strategy following PFO closure did not seem to impact clinical outcomes, thus challenging the current recommendations of temporary DAPT.

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.

Antiplatelet and Antithrombotic Therapy After Patent Foramen Oval and Atrial Septal Defect Closure

Pathologies of the atrial septum include different interatrial communications varying from patent foramen ovale (PFO) to actual defects. Atrial septal defects (ASDs) may be localized within the fossa ovalis such as the secundum type ASD or outside the region of fossa ovalis, such as the ostium primum defect and sinus venosus defect. Over the last decades, the percutaneous closure of interatrial shunts has become a feasible and safe method. During these procedures, the delicate balance between thrombotic risk, device sealing process and bleeding risk is crucial. In this review, we sought to describe current available data on the antiplatelet and antithrombotic management of patients after percutaneous ASD or PFO closure.

Antithrombotic/Antiplatelet Treatment in Transcatheter Structural Cardiac Interventions-PFO/ASD/LAA Occluder and Interatrial Shunt Devices

Transcatheter interventions enable safe and efficient treatment of various structural heart diseases. However, therapy does not finished with the end of the procedure. Device thrombosis is a possible serious complication. Therefore, careful patient management should include optimal antiplatelet or antithrombotic medication to enhance safe and complete endothelial coverage of the implanted device. In case of thrombus formation careful diagnostic evaluation and prompt treatment is crucial. This paper provides an update to current knowledge and understanding of prevention and management of device related thrombosis.

Changes in Coagulation and Platelet Activation Markers Following Transcatheter Left Atrial Appendage Closure

The recommendations for antithrombotic treatment after left atrial appendage closure (LAAC) remain empirical, and no data exist on the changes in hemostatic markers associated with LACC. The objective of the present study is to determine the presence, degree, and timing of changes in the markers of platelet and coagulation activation after LAAC. Forty-three patients (mean age 76 ± 9 years, 23 men) with atrial fibrillation who underwent successful LACC with the Watchman (n = 27) or Amplatzer Cardiac Plug (n = 16) devices were included in the study. Patients received antiplatelet therapy after LAAC (aspirin + clopidogrel: 27 patients; single antiplatelet therapy with aspirin or clopidogrel: 16 patients). Prothrombin fragment 1+2 and thrombin-antithrombin III were used as markers of coagulation activation, and soluble P-selectin and soluble CD40 ligand were used as markers of platelet activation. Measurements of all hemostatic markers were performed at baseline just before the procedure, followed by days 7, 30, and 180 after LAAC. Prothrombin fragment 1+2 and thrombin-antithrombin levels increased from 0.27 nmol/L and 4.68 ng/ml, respectively, at baseline to peak values of 0.43 nmol/L and 9.76 ng/ml, respectively, at 7 days, partially returning to baseline levels at days 30 and 180 after LAAC (p <0.001 for both markers). No clinical or procedural factors were associated with a greater increase in the markers of coagulation activation after LAAC. Levels of soluble P-selectin and soluble CD40 ligand did not change at any time after LAAC. In conclusion, transcatheter LAAC is associated with significant activation of the coagulation system, yet without evidence of significant platelet activation.

Mean platelet volume is elevated in patients with patent foramen ovale

INTRODUCTION

Platelets play a major role in thromboembolic events. Increased mean platelet volume (MPV) indicates higher platelet reactivity and also a tendency to thrombosis. Patent foramen ovale (PFO), persistence of the fetal anatomic shunt between right and left atria, is strongly associated with cryptogenic stroke. The aim of this study is to determine the relationship between MPV and PFO and if such an association exists, whether higher MPV levels may require antiplatelet therapy before a thromboembolic event happens, together with a literature review.

MATERIAL AND METHODS

Thirty patients (15 women, 15 men), free of any cerebrovascular events, were diagnosed with PFO by transesophageal echocardiography (TEE), enrolled as the study group. Thirty consecutive patients (16 women and 14 men), who were diagnosed as normal in TEE, were enrolled as the control group. These two groups were compared according to MPV and anatomical features of the right atrium.

RESULTS

There was no significant difference between study and control groups in clinical features and also no difference was observed in platelet counts; however, MPV in the PFO group was significantly higher than the control group (8.38 ±0.93 fl and 7.45 ±0.68 fl respectively).

CONCLUSIONS

Our results indicate that elevated MPV may be detected in patients with PFO. This might be one of the explanations for the relationship between PFO and cryptogenic stroke; however, larger cohorts are warranted in order to define further mechanisms.

Antithrombotic Strategies in Valvular and Structural Heart Disease Interventions: Current Status and Future Directions

Antithrombotic prophylaxis is the cornerstone of adjunctive pharmacologic therapy in patients undergoing transcatheter intervention for valvular and structural heart disease. However, drugs and doses of antiplatelet and anticoagulant agents are mostly empiric for these indications and typically administered at the operator's discretion. This article describes the rationale for antithrombotic management of patients undergoing transcatheter aortic valve implantation, percutaneous mitral valve repair with the Mitraclip system, patent foramen ovale, and atrial septal defect closure, as well as common strategies for managing antiplatelet and anticoagulant therapy in patients with valvular and structural heart disease undergoing transcatheter procedures.

The brain's heart - therapeutic opportunities for patent foramen ovale (PFO) and neurovascular disease

Patent foramen ovale (PFO), a common congenital cardiac abnormality, is a connection between the right and left atria in the heart. As a "back door to the brain", PFO can serve as a conduit for paradoxical embolism, allowing venous thrombi to enter the arterial circulation, avoiding filtration by the lungs, and causing ischemic stroke. PFO-related strokes affect more than 150,000 people per year in the US, and PFO is present in up to 60% of migraine patients with aura, and in one out of four normal individuals. So, in such a highly prevalent condition, what are the best treatment and prevention strategies? Emerging studies show PFO-related neurovascular disease to be a multi-organ condition with varying individual risk factors that may require individualized therapeutic approaches - opening the field for new pharmacologic and therapeutic targets. The anatomy of PFO suggests that, in addition to thrombi, it can also allow harmful circulatory factors to travel directly from the venous to the arterial circulation, a concept important in finding novel therapeutic targets for PFO-related neurovascular injury. Here, we: 1) review emerging data on PFO-related injuries and clinical trials; 2) discuss potential mechanisms of PFO-related neurovascular disease in the context of multi-organ interaction and heart-brain signaling; and 3) discuss novel therapeutic targets and research frontiers. Clinical studies and molecular mapping of the circulatory landscape of this multi-organ disease will both be necessary in order to better individualize clinical treatment for a condition affecting more than a quarter of the world's population.

Enhanced prothrombin formation and platelet activation in Chinese patients after transcatheter closure of atrial septal defect

BACKGROUND

The objective of this study was to investigate changes in coagulation activation and platelet activation after transcatheter closure of atrial septal defect (ASD) by determining the levels of specific markers over time to provide insight into preventing postprocedural embolism.

HYPOTHESIS

We hypothesis that the activation status of coagulation and the platelet would be changed after the closure of ASD.

METHODS

Forty consecutive patients who underwent transcatheter closure of ASD with the Lifetech ASD occluder (Lifetech Scientific, Shenzhen, China) were included in this prospective study. The serum level of prothrombin fragment 1 + 2 (F1 + 2) and expressions of P-selectin (CD62P) and platelet glycoprotein IIb/IIIa receptor (CD41a) on the surface of platelets were evaluated at baseline and at 1 day, 1 month, and 3 months after the closure.

RESULTS

The median F1 + 2 level was 0.96 nmol/L. This increased to a maximal value of 1.43 nmol/L at 1 day after closure, but gradually returned to the baseline level at 1 month after closure and remained there at 3 months after closure (medians were 0.98 nmol/L and 1.08 nmol/L, respectively). Platelet surface expression of CD62P and CD41a decreased at 1 day, 1 month, and 3 months after closure. For CD62P, average expressions were 8.21% +/- 2.11%, 6.28% +/- 1.72%, 5.29% +/- 1.52%, and 4.41% +/- 1.11%, respectively, for baseline and 1 day, 1 month, and 3 months after closure. For CD41a, average expressions were 79.37% +/- 14.14%, 71.98% +/- 13.77, 56.69% +/- 13.05%, and 54.88% +/- 11.62%, respectively.

CONCLUSIONS

Transcatheter closure of ASD with the Lifetech ASD occluder was associated with significantly increased coagulation activation and decreased platelet activation. No evidence supporting the use of aspirin to prevent thrombus formation after closure was found.

Altered fibrin clot structure/function in patients with cryptogenic ischemic stroke

BACKGROUND AND PURPOSE

We tested the hypothesis that fibrin structure/function is unfavorably altered in patients with cryptogenic ischemic stroke.

METHODS

Ex vivo plasma fibrin clot permeability, turbidimetry, and efficiency of fibrinolysis were determined in 89 patients with patent foramen ovale (PFO) and a history of first-ever stroke, 58 patients with first-ever stroke and no PFO, and 120 healthy controls.

RESULTS

Stroke patients, evaluated 3 to 19 months after the event, and controls did not differ with regard to age, sex, smoking, and fibrinogen. Stroke patients with or without PFO had lower clot permeability (P<0.0001), faster fibrin polymerization (P<0.0001), prolonged clot lysis time (P<0.0001), higher maximum D-dimer levels released from clots (P<0.0001), and maximum rate of D-dimer release (P=0.02) than controls. Time from stroke occurrence showed no association with any clot variables. Scanning electron microscopy of fibrin clots showed increased fiber diameter and density in stroke patients. Clots from stroke patients with PFO were more permeable and showed shorter lysis time compared to those without PFO, and this was related to lower proportion of smokers in the former group.

CONCLUSIONS

Altered fibrin clot structure and resistance to fibrinolysis are associated with cryptogenic stroke.

Atherosclerotic Burden Findings in Young Cryptogenic Stroke Patients With and Without a Patent Foramen Ovale

Background and Purpose— To further determine the mechanisms of cryptogenic stroke or transient ischemic attack in young patients, we evaluated indices of atherosclerosis in patients ≤55 years old diagnosed with cryptogenic cerebrovascular event comparing those with patent foramen ovale (PFO) with those without PFO.

Methods— This was a prospective study including 100 consecutive patients ≤55 years old (mean age, 45±8 years; 56 males) diagnosed with cryptogenic stroke/transient ischemic attack. PFO was identified in 59 of these patients with the use of transesophageal echocardiography with contrast study. The following surrogate markers of atherosclerosis were evaluated in all patients: carotid intima media thickness as measured by carotid ultrasonography and endothelial function as determined by brachial flow-mediated vasodilation. The same measurements were obtained in a control group of 50 age- and sex-matched control subjects.

Results— Patients without PFO were more likely to be current smokers and obese and more frequently had a history of hypertension and dyslipidemia. Carotid intima media thickness measurements were higher ( P <0.0001) in patients without PFO (1.03±0.31 mm) compared with those with PFO (0.75±0.20 mm) and control subjects (0.79±0.17 mm). The absence of PFO was also associated with lower brachial flow-mediated vasodilation (without PFO: 5.04±3.39%; with PFO: 7.16±4.09%; control subjects: 7.33±4.07%; P =0.02). There were no differences in carotid intima media thickness and flow-mediated vasodilation between patients with stroke/transient ischemic attack with PFO and control subjects. The presence of PFO was independently associated with reduced carotid intima media thickness ( P <0.0001) and increased flow-mediated vasodilation ( P =0.019).

Conclusions— In patients ≤55 years old diagnosed with cryptogenic stroke/transient ischemic attack, the presence of PFO was associated with a lower atherosclerotic burden as measured by carotid intima media thickness and endothelial function with no differences compared with a control group without cerebrovascular event. These results suggest that an atherosclerotic-mediated mechanism may be involved in cryptogenic stroke/transient ischemic attack in patients without PFO, whereas a nonatherosclerotic mechanism may mediate the cerebrovascular event in the presence of PFO.

Incidence, timing, and predictive factors of new-onset migraine headache attack after transcatheter closure of atrial septal defect or patent foramen ovale

The objectives of this study were to evaluate the incidence, predictive factors, and duration of migraine headache attack (MHA) after transcatheter atrial septal defect (ASD) or patent foramen ovale (PFO) closure. A total of 260 consecutive patients who underwent ASD or PFO closure in our center answered a structured headache questionnaire focused in 3 period times, including (1) at baseline (just before closure), (2) within the 3 months after ASD-PFO closure, and (3) at the last (median 27 months, range 6 to 80 months) follow-up. All questionnaires were evaluated by a neurologist who established the diagnosis of MHA with or without aura, according to International Headache Society criteria. The Amplatzer ASD or PFO device was used in 95% of the patients, and aspirin, for at least 6 months, was the antithrombotic treatment in 91% of the cases. A total of 185 patients (71%) had no history of MHA before ASD-PFO closure, and these constituted the study population (mean age 39 +/- 21 years). MHA occurred in 13 patients (7%) after ASD-PFO closure, with aura in 9 of them. MHA appeared after a median of 10 days (range 0.3 to 30 days) after the procedure and were still present at the last follow-up (23 +/- 17 months) in 9 patients (69%). The median number of MHA within the 3 months after the procedure was 4 per month (interquartile range 1 to 23), and decreased to 1 per month (interquartile range 0.3 to 1) at the latest follow-up (p = 0.03). Compared with the patients who did not develop MHA, patients with MHA after ASD-PFO closure were younger (26 +/- 16 vs 39 +/- 21 years; p = 0.02) and were more likely to have undergone ASD closure (100% vs 58%; p = 0.001). In the multivariate analysis, ASD closure was the only predictor of MHA occurrence after the procedure (odds ratio 7.7; 95% confidence interval 1.5 to 22; p = 0.01). In conclusion, MHA, mostly with aura, occurred in 7% of patients after transcatheter ASD-PFO closure and persisted in most of them after a mean follow-up of 2 years. ASD closure was the only independent predictor of MHA occurrence after the procedure. These results suggest that mechanisms other than device composition are involved in the occurrence of MHA in these cases.

The Quebec Heart Institute: 50 years of excellence in cardiology

The Quebec Heart Institute was established in 1957 at the Laval Hospital in Sainte-Foy, Quebec. Since then, clinical and research activities have made this Institute one of the largest tertiary care cardiology centres in Canada. With its vast catchment area of more than 3,000,000 people, the Institute has developed a strong collaboration with referral physicians centred on clinical, teaching and research interests. The Institute pioneered several aspects of cardiac surgery, invasive cardiology, echocardiography, basic research and, more recently, a network of researchers and clinicians working in the field of 'metabolic cardiology'. The first 50 years of the Quebec Heart Institute are depicted in this overview, which will also introduce this special supplement to The Canadian Journal of Cardiology.

[Patent foramen ovale percutaneous closure: indications, techniques and results]

A patent foramen ovale is almost physiological (15% of the population) but can be associated with some pathological situations in which its closure can be considered. The only medical indication currently accepted is a right-left shunt without elevation of the right pulmonary pressure, whose most famous pattern is the rare platypnea-orthodeoxie syndrome. PFO may be responsible for diving decompression accidents. Before taking the decision of closing a PFO, each situation must be discussed on a case to case basis. In spite of the possible link between some kinds of migraine and PFO, according to current knowledge, there is no evidence of the efficiency of PFO closure in this situation. The secondary prevention of a cryptogenic ischaemic cerebrovascular attack on a young person with a PFO associated to a membranous septum aneurysm, is the most commonly considered indication, but we lack valid data for this indication. The PFO closing procedure is well codified and its success rate is close to 100%, with rare major complications. Residual permeability within the prosthesis ensuring the closure of the PFO decreases gradually to get under 15% after six months. The clinical result is often dramatic when treating right-left shunts. As far as the secondary prevention of cryptogenic ischaemic cerebro vascular attacks in young people is concerned, there might be some clinical benefit, but we are waiting for the results of ongoing randomized and scheduled studies.