Patent foramen ovale closure in patients with transient ischemia attack/stroke

A Systematic Review and Meta-Analysis of the Association between Residual Shunts after Patent Foramen Ovale Closure and Long-Term Cerebrovascular Events

BACKGROUND

The association between a patent foramen ovale (PFO) and cryptogenic stroke (CS) is well established, and the benefits of PFO closure are clearly recognized. This study aimed to investigate the presence of a residual shunt in patients who have experienced cryptogenic cerebrovascular events following a PFO closure.

METHODS

Two researchers systematically searched the PubMed and Embase online database for pertinent clinical studies published between January 2000 and July 2021 concerning the recurrence of cerebrovascular events after PFO closures.

RESULTS

Upon screening an initial list of 2,342 articles, six studies were identified, involving 2,083 patients. Overall, the analysis indicated a marked difference in the recurrence of cerebrovascular events in 8.89% of residual shunt (RS) cases compared to only 2.90% of non-RS cases. The summary odds ratio was 3.484 (95% confidence interval, 2.169-5.596), which suggested that RS may be a risk factor for recurrent cerebrovascular events in patients that experienced PFO-related cerebrovascular events within 6 months after PFO closure surgery.

CONCLUSIONS

The presence of RS significantly increases the risk of recurrent cerebrovascular events in patients with clinical PFO closure.

Interventional prevention of paradoxical embolism as the gold standard: End of discussion?

Paradoxical embolism is one of the predominant causes of cryptogenic stroke and interventional secondary prevention, i.e., closure of the patent foramen ovale (PFO), is a much discussed issue. This review aims to provide a complex perspective on this topic, aggregates and comments on the available data and current guidelines. Several large trials were performed, some of which proved the superiority of PFO closure over pharmacotherapy while others have not. Studies detecting significant superiority of intervention worked with disproportionately high representation of large shunts compared to the general population. Other controversies also remain, such as the lack of comparison of the effect of modern anticoagulant/antiplatelet treatment to PFO closure or the risk of developing unwanted side effects after intervention, and these are discussed in detail. PFO closure is a suitable method for secondary prevention of paradoxical embolism and, therefore, cryptogenic stroke. However, this is only true for carefully selected patient populations and such selection is of the utmost importance in deciding on interventional or conservative treatment.

Closure or medical therapy of patent foramen ovale in cryptogenic stroke: prospective case series

Background

Results of randomized controlled trials (RCT) do not provide definite guidance for secondary prevention after ischemic stroke (IS)/transient ischemic attack (TIA) attributed to patent foramen ovale (PFO). No recommendations can be made for patients > 60 years. We aimed to compare interventional and medical PFO-management in cryptogenic IS/TIA patients, including patients > 60 years.

Methods

Prospective case series including consecutive cryptogenic IS/TIA patients with PFO at Tuebingen university stroke unit, Germany. ‘PFO-closure’ was recommended in patients ≤70 years when featuring high-risk PFO (i.e., with atrial septal aneurysm, spontaneous, or high-grade right-to-left shunt during Valsalva). Primary (recurrent IS/intracranial hemorrhage) and secondary endpoints (e.g., disability) were assessed during ≥1-year follow-up; planned subgroup analyses of patients ≤60/> 60 years.

Results

Among 236 patients with median age of 58 (range 18–88) years, 38.6% were females and median presenting National Institutes of Health Stroke Scale score was 1 (IQR 0–4). Mean follow-up was 2.8 ± 1.3 years. No intracranial hemorrhage was observed. Recurrent IS rate after ‘PFO-closure’ was 2.9% (95%CI 0–6.8%) and 7% (4–16.4) in high-risk PFO patients ≤60 (n = 103) and > 60 years (n = 43), respectively, versus 4% (0–11.5) during ‘medical therapy alone’ MTA (n = 28). 42 low-risk PFO patients treated with MTA experienced no recurrent IS/TIA.

Conclusions

In our real-world study, IS recurrence rate in ‘PFO-closure’ high-risk PFO patients ≤60 years was comparable to that observed in recent RCT. High-risk PFO patients > 60 years who underwent PFO-closure had similar IS recurrence rates than those who received MTA. MTA seems the appropriate treatment for low-risk PFO.

Trial registration

ClinicalTrials.gov, registration number: NCT04352790, registered on: April 20, 2020 – retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42466-021-00114-3.

Hemodynamic, biological, and right ventricular functional changes following intraatrial shunt repair in patients with flow-induced pulmonary hypertension

OBJECTIVES

Atrial septal defects may result in pulmonary hypertension and right heart remodeling. We analyzed improvements in patients with flow-induced pulmonary hypertension and the activation of endothelial progenitor cells after flow reduction.

DESIGN

This prospective cohort study included 37 patients who were admitted for an occluder implantation. Blood samples were collected before and after the procedure. We determined the number of endothelial progenitor cells in outgrowth colonies and serum Hsp27 concentrations. Daily performance and cardiothoracic ratio were reevaluated later.

RESULTS

Closure of the defect significantly reduced the pulmonary pressure and B-type natriuretic peptide levels. The cardiothoracic ratio and daily performance status also improved. The number of endothelial progenitor cell outgrowth colony-forming units significantly increased and was positively correlated with daily performance. In patients with enhanced colony formation, Hsp27 levels were significantly increased.

CONCLUSIONS

The implantation of an occluder successfully improved hemodynamic, right ventricular, and daily performance. Qualitative enhancement of colony formation for endothelial progenitor cells was also noted and positively correlated with daily performance. Closure of defects may serve as a valid, reliable model to obtain a deeper understanding of the modulation of endothelial progenitor cell activity and its relationship with pulmonary hypertension prognosis.

Therapeutic Utilities of Pediatric Cardiac Catheterization

In an era when less invasive techniques are favored, therapeutic cardiac catheterization constantly evolves and widens its spectrum of usage in the pediatric population. The advent of sophisticated devices and well-designed equipment has made the management of many congenital cardiac lesions more efficient and safer, while providing more comfort to the patient. Nowadays, a large variety of heart diseases are managed with transcatheter techniques, such as patent foramen ovale, atrial and ventricular septal defects, valve stenosis, patent ductus arteriosus, aortic coarctation, pulmonary artery and vein stenosis and arteriovenous malformations. Moreover, hybrid procedures and catheter ablation have opened new paths in the treatment of complex cardiac lesions and arrhythmias, respectively. In this article, the main therapeutic utilities of cardiac catheterization in children are discussed.

Recurrent and Residual Shunts After Patent Foramen Ovale Closure: Results From a Long-Term Transcranial Doppler Study

OBJECTIVES

Assess the evolution of right-to-left shunt (RLS) after transcatheter patent foramen ovale (PFO) closure.

BACKGROUND

Despite the high number of interventional procedures performed worldwide, limited systematic data on the long-term abolition of RLS after percutaneous closure are available.

METHODS

All patients treated at our Institution between February 2001 and July 2009 were included in this single center, prospective study, and were asked to repeat late contrast transcranial Doppler (cTCD). Rate of complete closure, residual RLS (i.e., a shunt that persists after closure), and recurrent RLS (i.e., a shunt that reappears after a previous negative cTCD) was assessed.

RESULTS

Long-term follow-up was completed in 120 patients (56% male). RLS was still detectable 4.9 ± 2.3 years (range 1.3-10.3) after the procedure in 55 patients; 20 (17%) had residual RLS and 35 (29%) had recurrent RLS. Multivariate analysis revealed that significant predictors of residual RLS included post-procedural shunt at transesophageal echocardiography (OR 3.07, 95%CI 0.97-9.7), use of a bigger device (35 vs 25 mm, OR 3.85, 95%CI 1.22-12.2) and length of follow-up (OR 0.75, 95%CI 0.57-0.98), while only length of follow-up (OR 0.77, 95%CI 0.62-0.95) was associated with recurrent RLS. Neurological recurrences (1 stroke, 6 transient ischemic attacks) were equally distributed between the groups.

CONCLUSION

A significant number of recurrent and residual shunts may be observed by cTCD up to 5 years after PFO closure. Management of late RLSs includes periodic re-evaluation, exclusion of device-induced complications or secondary sources of RLS, and optimization of antithrombotic treatment with or without a second intervention.

A rare case of right ventricular myxoma causing recurrent stroke

We present a 62-year-old lady admitted in our hospital with two episodes of acute ischemic stroke about 2 weeks apart. She was evaluated for acute ischemic stroke and was thrombolysed for recent stroke in right MCA territory first time. On further evaluation, she was found to have a RVOT mass. A transthoracic and transesophageal echocardiogram revealed a PFO and a large, 5.1 cm × 2.3 cm, ovoid, well circumscribed, echogenic mass in the right ventricle outflow tract attached by small pedicle to the ventricular side of anterior tricuspid leaflet, partly obstructing the right ventricular outflow tract and protruding through the pulmonic valve during systole. She was scheduled for surgery (right ventricular mass excision and PFO closure) after 3 weeks due to the risk of secondary hemorrhage in the infarcted area following thrombolysis and anticoagulation and so was discharged with medications after full neurologic recovery after about a week of hospital stay.

She was readmitted 7 days after discharge, before the scheduled date of surgery with history of weakness of right upper limb, slurred speech and mild breathing difficulty lasting for about 20 min following which she improved slowly (transient ischemic attack). The tumor was completely removed with the stalk using cardiopulmonary bypass support. The histopathological findings confirmed the diagnosis of myxoma.

Initial clinical experience with the Coherex FlatStent™ and FlatStent™ EF PFO closure system for in-tunnel PFO closure: results of the Coherex-EU study

OBJECTIVE

The Coherex-EU Study evaluated the safety and efficacy of PFO closure utilizing novel in-tunnel PFO closure devices.

BACKGROUND

Transcatheter closure of patent foramen ovale (PFO) followed the development of transcatheter closure devices designed to patch atrial septal defects (ASDs). The Coherex FlatStent™ and FlatStent™ EF devices were designed specifically to treat PFO anatomy.

METHODS

A total of 95 patients with a clinical indication for PFO closure were enrolled in a prospective, multicenter first in man study at six clinical sites. Thirty-six patients received the first-generation FlatStent study device, and 57 patients received the second-generation FlatStent EF study device, which was modified based on clinical experience during the first 38 cases. Two patients enrolled to receive the first generation did not receive a device.

RESULTS

At 6 months post-procedure, 45% (17/38) of the intention-to-treat (ITT) cohort receiving the first-generation FlatStent device had complete closure, 26% (10/38) had a trivial residual shunt, and 29% (11/38) had a moderate to large residual shunt. In the ITT cohort receiving the second-generation FlatStent EF device, 76% (43/57) had complete closure, 12% (7/57) had a trivial shunt, and 12% had a moderate to large shunt. Five major adverse events occurred, all without sequelae.

CONCLUSION

This initial study of the Coherex FlatStent/FlatStent EF PFO Closure System demonstrated the potential for in-tunnel PFO closure. The in-tunnel Coherex FlatStent EF may offer an alternative to septal repair devices for PFO closure in appropriately selected patients; however, further investigation will be necessary to establish the best use of this device.

Amplatzer occluder versus CardioSEAL/STARFlex occluder: a meta-analysis of the efficacy and safety of transcatheter occlusion for patent foramen ovale and atrial septal defect

OBJECTIVE

Percutaneous transcatheter occlusion has benefited thousands of patients suffering from patent foramen ovale and atrial septal defect. However, no general agreement has been reached on the superiority among occluders. Thus, a meta-analysis between the two most commonly adopted types of occluders was conducted.

METHODS

The literature review has identified relevant studies up to May, 2011 in the databases of PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and World Health Organization clinical trials registry centre. Meta-analysis was performed in a fixed/random effects model using Revman 5.1.1. Information on complications and outcomes was extracted.

RESULTS

Analysis from included studies reports an outcome in favour of the Amplatzer. The Amplatzer has proven its superiority in efficacy with a significantly lower risk of early (95% confidence interval = 0.09-0.34) and long-term (95% confidence interval = 0.14-0.97) residual shunt rate for atrial septal defect occlusion, although no significant difference in performance has been reported for patent foramen ovale. In addition, the Amplatzer has also remarkably reduced the risk of embolisation by the device (95% confidence interval = 0.07-0.45) for atrial septal defect and new-set atrial fibrillation (95% confidence interval = 0.18-0.48) for patent foramen ovale. On evaluation of recurrent thrombotic events, it was found that the Amplatzer greatly lowered the rate of thrombus formation on the device (95% confidence interval = 0.02-0.21) for patent foramen ovale; however, no statistical difference was found on atrial septal defect evaluation. However, the result indicated no statistically significant difference between the two kinds of occluders in stroke and transient ischaemic attack of patent foramen ovale.

CONCLUSION

The meta-analysis has proven the Amplatzer to be the superior occluder, serving better prognosis with more fluent procedure and less complications.

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.

Closure or medical therapy for cryptogenic stroke with patent foramen ovale

BACKGROUND

The prevalence of patent foramen ovale among patients with cryptogenic stroke is higher than that in the general population. Closure with a percutaneous device is often recommended in such patients, but it is not known whether this intervention reduces the risk of recurrent stroke.

METHODS

We conducted a multicenter, randomized, open-label trial of closure with a percutaneous device, as compared with medical therapy alone, in patients between 18 and 60 years of age who presented with a cryptogenic stroke or transient ischemic attack (TIA) and had a patent foramen ovale. The primary end point was a composite of stroke or transient ischemic attack during 2 years of follow-up, death from any cause during the first 30 days, or death from neurologic causes between 31 days and 2 years.

RESULTS

A total of 909 patients were enrolled in the trial. The cumulative incidence (Kaplan-Meier estimate) of the primary end point was 5.5% in the closure group (447 patients) as compared with 6.8% in the medical-therapy group (462 patients) (adjusted hazard ratio, 0.78; 95% confidence interval, 0.45 to 1.35; P=0.37). The respective rates were 2.9% and 3.1% for stroke (P=0.79) and 3.1% and 4.1% for TIA (P=0.44). No deaths occurred by 30 days in either group, and there were no deaths from neurologic causes during the 2-year follow-up period. A cause other than paradoxical embolism was usually apparent in patients with recurrent neurologic events.

CONCLUSIONS

In patients with cryptogenic stroke or TIA who had a patent foramen ovale, closure with a device did not offer a greater benefit than medical therapy alone for the prevention of recurrent stroke or TIA. (Funded by NMT Medical; ClinicalTrials.gov number, NCT00201461.).

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.

The incidence of peripheral arterial embolism in association with a patent foramen ovale (right-to-left shunt)

Objectives

The aim of this study was to examine a cohort of patients who had suffered an arterial embolism to see whether a patent foramen ovale (PFO) was an identifiable cause.

Design

This study was conducted in two parts; a retrospective limb involving an audit of patient records over a period of 10 years, and a prospective limb including selected patients from that audit to search for a PFO using an agitated saline test with transcranial Doppler ultrasound monitoring of the anterior cerebral artery. Data on patients with peripheral vascular disease were collected using a structured questionnaire.

Setting

A clinical vascular department. All patients were seen in the vascular outpatients clinic.

Participants

Patients who had been identified from a retrospective search based on the headline diagnosis of arterial embolus. Collected data on the 71 patients revealed that 75% had predisposing factors for DVT, 70% were male smokers, and 84.4% had a significant past history of vascular symptoms.

Main outcome measures

Whether or not patients identified as having a possible PFO actually had one on objective testing with transcranial Doppler assessment of the cerebral circulation with an agitated saline solution.

Results

Fifteen patients who were suspected of having a PFO were selected from these 71 patients; 12 of these were found to have no PFO on testing, and three had already undergone a percutaneous PFO closure.

Conclusion

The incidence of a PFO in this small study group is no higher than that found in the general population (3/15, 20%). There was high prevalence of male smokers with associated predisposing factors leading to a DVT.

Cardioembolic stroke: who is the guilty?

A young woman was referred following a transient ischemic attack due to suspect patent foramen ovale. At the diagnostic workup a spontaneous mild right-to-left atrial shunt owing to fenestrated aneurysmal septum was found. However, also a large arteriovenous malformation of the left lung was also imaged. At interventional cardiac catheterization, both malformations were closed using an Amplatzer Cribriform occluding device and a Amplatzer Vascular Plug II, respectively. In conclusion, patent foramen ovale is just one of the potential causes of cardioembolic stroke and a thorough diagnostic workup is mandatory after a cryptogenic stroke to rule out any additional source of paradoxical embolism.

A suture not always the ideal solution: problems encountered in developing a suture-based PFO closure technique

OBJECTIVES

To summarize our experiences with the first-in-man suture-based patent foramen ovale (PFO) closure technique.

BACKGROUND

PFO is often present with the occurrence of cryptogenic stroke and migraine with aura. Successful PFO closure can be performed percutaneously using catheter techniques with many different closure devices. The described novel closure system is intended to deliver, via endovascular access, a suture into the atrial septal wall tissue for closure of PFO.

METHODS

Eleven patients, between 22 and 58 years of age (mean 46.6 +/- 9.6), who had a cryptogenic ischemic stroke, TIA, or a peripheral embolism and a PFO were considered for percutaneous closure with this technique.

RESULTS

The mean stretched diameter of the defect evaluated during balloon sizing was 8.8 +/- 0.4 mm (range 7-12.5). Delivery of the suture was successful in all patients. No intraprocedural complications occurred. During the follow up, complete closure could be achieved in one patient. Six patients with significant residual shunting during follow-up had successful closure using a conventional device. One patient was lost for follow-up after the 3-month visit. The residual shunt in the remaining three patients was very small and they declined to be treated with a conventional device. No complications occurred during the follow up.

CONCLUSIONS

Transcatheter application of a suture for closure of PFO is technically feasible and safe. However, despite successful suturing of the septum primum to the septum secundum, the PFO did not close in most of the patients.

Cryptogenic stroke in a patient with a PFO: a decision analysis

BACKGROUND

Octogenarian Israeli prime-minister Ariel Sharon recently sustained a mild, reversible stroke. A patent foramen ovale (PFO) was detected and anticoagulants were given pending PFO closure. A few days later, he sustained major intracerebral hemorrhage and has since remained in vegetative state. The events triggered serious criticism in the mass media, experts promoting one management option over others. Because knowledge of outcome and hindsight bias evaluation of appropriateness of care, we sought to systematically review the clinical case.

METHODS

We performed a formal decision analysis to identify the preferred management between anticoagulation, antiplatelets, PFO closure, or no treatment. Using the best evidence available, we built a decision tree.

MAIN OUTCOMES

recurrent stroke and treatment complications within 1 year.

RESULTS

Optimal decision was found to be critically sensitive to assumptions about etiology, efficacy and safety of treatments, recurrence risk, and to small changes in utilities. In multiway sensitivity analysis, when the risk of recurrent stroke was <0.12 per year, no treatment was the best management. PFO closure is dominant only when the risk of recurrent stroke is >0.12 per year closure effectiveness is assumed to be <0.28. When closure effectiveness is >0.6, it is inferior to anticoagulation and antiplatelet management.

CONCLUSIONS

Uncertainties precluded a clear-cut answer and choice was found to be a "toss-up," often associated with much controversy. Use of novel therapies, such as PFO closure, outside clinical trials will not reduce uncertainty about efficacy.

Causes of recurrent focal neurologic events after transcatheter closure of patent foramen ovale with the CardioSEAL septal occluder

Transcatheter patent foramen ovale (PFO) closure has been undertaken to eliminate paradoxical emboli as a cause for recurrent strokes/transient ischemic attacks (TIAs). We report the results of investigations to determine causes of all significant focal neurologic events (FNEs) after PFO closure reported to our center. Records of 216 consecutive patients who underwent PFO closure were reviewed. Patients had to have had > or =1 preceding clinical event consistent with stroke/TIA considered by a neurologist to be consistent with an embolic episode. Follow-up was recommended at 24 hours, 1 month, 6 months, 1 year, and every 1 to 2 years thereafter. All patients were requested to report any new FNE possibly suggestive of stroke/TIA to our center. Reports of evaluations were reviewed in detail. Twenty patients had an FNE 0.1 month to 40.2 months after PFO closure over 438 person-years of follow-up (mean 2.1 years, range 1 month to 7.1 years). There were 4 recurrent strokes, 2 likely directly device related. Ten patients had TIA and 6 patients had clear evidence of pathology unrelated to the device. Event rate for recurrent strokes was 0.9% per year (95% confidence interval for difference 0.3 to 2.4) and combined event rate for stroke/TIA was 3.4% per year (95% confidence interval for difference 2 to 5.6). In conclusion, transcatheter PFO occlusion can be accomplished as an outpatient procedure with minimal immediate morbidity. Patients may have multiple possible causes of recurrent FNE. Recurrence rate of cryptogenic FNE compares favorably with reports of medical management. Analysis of results from ongoing randomized trials of transcatheter PFO closure versus medical management may improve our ability to select the best treatment for individual patients.

Mechanisms underlying air aspiration in patients undergoing left atrial catheterization

BACKGROUND

Air embolism in patients undergoing percutaneous interventions requiring access to the left atrium (LA) represents a potentially fatal complication. Here we tested if a decline in LA pressures following sedation represents an important mechanistic link underlying air intrusion into the LA.

METHODS AND RESULTS

Left atrial pressures were measured in 26 consecutive patients (49 +/- 14 years; 27% male), who underwent percutaneous atrial septal occlusion for persistent foramen ovale or secundum atrial septal defects. Patients either received sedation by propofol allowing for guidance by transesophageal echocardiography (n = 13) or underwent occluder implantation without sedation and under fluoroscopic control only (n = 13). Whereas mean expiratory LA pressures remained unchanged in either group, sedation provoked a marked decline in the mean inspiratory LA pressure as compared to non-sedated patients (Delta p 6.9 +/- 8.6 mm Hg vs. 0.1 +/- 1.2 mm Hg in nonsedated patients, P < 0.001). Ex vivo experiments evaluating the air-tightness of different sheaths in response to negative pressures revealed air aspiration at -13.4 +/- 1.2 mm Hg of suction in all cases, once a guide wire was inserted.

CONCLUSIONS

Negative LA pressures in conjunction with air-leaking sheaths are identified as potentially important factors for air intrusion into the LA with the patient's sedation being a primary risk factor to lower LA pressure levels. The results advocate close monitoring of LA pressures during intervention, prevention of airway collapse and protection of LA sheaths from communication with the atmosphere, during procedures under sedation.

[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.

Percutaneous devices for stroke prevention

The most important approaches to prevent cerebral ischemia by catheter technique are patent foramen ovale (PFO) closure in patients with a history of cryptogenic stroke and left atrial appendage (LAA) occlusion in atrial fibrillation (AF) patients. Over the past years, several new devices have been developed for these procedures. Results of randomized trials comparing device therapy, antiplatelet, or anticoagulation therapy are still not available. However, several nonrandomized studies have shown promising results. This article gives a review on the current results and techniques of the most commonly used devices as well as on new developments and approaches to catheter-based stroke prevention.

Results of the U.S. Multicenter Pivotal Study of the HELEX Septal Occluder for Percutaneous Closure of Secundum Atrial Septal Defects

OBJECTIVES

This study sought to compare the safety and efficacy of the HELEX septal occluder (HSO) with surgical repair of atrial septal defect (ASD).

BACKGROUND

The HSO is a low-profile, double-disk occluder device for percutaneous closure of secundum ASD.

METHODS

Patients were enrolled (HSO arm prospectively, surgery arm prospectively/retrospectively) from 14 U.S. sites and followed up for 12 months postprocedure. Investigator-reported outcomes were evaluated, including closure success (no or clinically insignificant residual shunt) and the incidence of adverse events. The first 3 HSO patients at each site were considered training cases and were excluded from analysis.

RESULTS

Between March 2001 and April 2003, 119 nontraining cases received an HSO and 128 had surgical repair. The groups were similar with statistical but clinically unimportant differences in median age, weight, and preprocedural echocardiographic defect size. Anesthesia time and hospital stay were significantly shorter in the HSO group. Closure success, defined as complete closure or a clinically insignificant residual shunt, was similar in both groups. Major and minor adverse events rates were not statistically different. The most common major adverse events for the HSO group was device embolization requiring catheter retreival (1.7%), and in the surgery group was postpericardiotomy syndrome (6.3%), including one death because of tamponade. The primary end point, clinical success, a composite of closure success and no major adverse events at 12 months, satisfied the noninferiority hypothesis comparing device closure with surgery.

CONCLUSIONS

Closure of ASD with the HELEX septal occluder is safe and effective when compared with surgical repair, with reduced anesthesia time and hospital stay. (U.S. Multicenter Pivotal Study of the HELEX Septal Occluder for Percutaneous Closure of Secundum Atrial Septal Defects; this study was approved by the Food and Drug Administration before the National Institutes of Health website was active, so there is not a URL or registration number.).

Patent foramen ovale and cryptogenic stroke. A critical review

The underlying causes of ischemic stroke in young patients are often difficult to find, despite systematic investigations concerning heart, coagulation system or any other type of vascular disease, thus the definition of 'cryptogenic'. In patients with cryptogenic stroke, the prevalence of a patent foramen ovale is about 45%, versus 25% of the general healthy population, leading to many speculations about a potential role of intracardiac right-to-left shunts in determining ischemic cerebral disease. Since a possible mechanism has been thought to be paradoxical embolism, percutaneous closure of the foramen ovale is currently discussed, at least until the appearance of data from the ongoing randomized trials. However, recurrent paradoxical embolism in patients with an aneurysmal atrial septum and a patent foramen ovale is currently the only unequivocal indication for percutaneous closure. Professional divers may benefit from the procedure as well, whereas migraine is still not considered an indication. In the pediatric population, closure of the patent foramen ovale seems to be safe and effective to prevent recurrent stroke. As the complication rate for device implantation decreases, the threshold for percutaneous closure is likely to decline.

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

BACKGROUND AND PURPOSE

No studies have yet determined whether antiplatelet or anticoagulant therapy is the more appropriate treatment after transcatheter closure of patent foramen ovale (PFO) in patients with cryptogenic stroke. The objective of this study was to prospectively evaluate the presence, degree, and timing of activation of the platelet and coagulation systems after transcatheter closure of PFO in patients with cryptogenic stroke.

METHODS

Twenty-four consecutive patients (mean age, 44+/-10 years; 11 men) with previous cryptogenic stroke who had undergone successful transcatheter closure of PFO were included in the study. Prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin III (TAT) 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 taken at baseline just before the procedure and at 7, 30, and 90 days after device implantation.

RESULTS

F1+2 and TAT levels increased from 0.41+/-0.16 nmol/L and 2.34+/-1.81 ng/mL, respectively, at baseline to a maximal value of 0.61+/-0.16 nmol/L and 4.34+/-1.83 ng/mL, respectively, at 7 days, gradually returning to baseline levels at 90 days (P<0.001 for both markers). F1+2 and TAT levels at 7 days after PFO closure were higher than those obtained in a group of 25 healthy controls (P<0.001 for both markers). Levels of soluble P-selectin and soluble CD40 ligand did not change at any time after PFO closure.

CONCLUSIONS

Transcatheter closure of PFO is associated with significant activation of the coagulation system, with no increase in platelet activation markers. These findings raise the question of whether optimal antithrombotic treatment after PFO closure should be short-term anticoagulant rather than antiplatelet therapy.

Transcatheter devices used in the management of patients with congenital heart disease

The availability of transcatheter devices has revolutionized the management of patients with congenital heart and vascular disease. Many patients that were in the past exclusively treated through open heart surgical procedures can now be managed using a percutaneous approach. This article describes those devices that are, at present, most frequently used in the USA for transcatheter therapy of congenital heart disease, which have, or are about to receive, US premarket approval. It also focuses on devices for occlusion of septal defects and vascular structures, as well as endovascular stents. In addition, the most important outcome data are discussed.

Thrombosis after septal closure device placement: a review of the current literature

Thrombus formation has been described for all types of commercially available transcatheter septal occlusion devices. Most reports have been single-institution case studies. Screening for hypercoagulable conditions prior to device placement and anticoagulation after device deployment has been variable. The objective of this study was to synthesize the current experience with device thrombosis; the Medline database from 1980 until 2004 was searched. Seventeen articles identified 54 unique patients with device thrombosis. Thrombus developed on eight different types of transcatheter devices. All commercially available devices had at least one reported case of thrombosis. Patient mean age was 44.2 +/- 9.8 years. Thrombosis was diagnosed at a mean of 5 months after device deployment. Prior to device placement, 12 patients had normal coagulation evaluations and 5 had coagulopathies. For 37 patients, no mention was made in the report of coagulation studies. Prior to device thrombosis, 26 patients received aspirin and clopidogrel, 15 patients received aspirin alone, 8 received warfarin, 2 heparin alone, 1 aspirin and warfarin. One patient with hemophilia A received no anticoagulation and in one case treatment prior to thrombosis was not reported. After device thrombosis, 35 patients were treated with warfarin with thrombus resolution, 2 had successful lytic therapy, 1 was treated with heparin alone. Sixteen patients had surgical explantation of the device. Septal occlusion device thrombosis is rare. All types of commercially available devices have been associated with thrombosis. All patients should have early (< or = 3 months) echocardiographic surveillance for device thrombosis. Thorough coagulation evaluation is imperative prior to transcatheter device placement.

First experience with the 2005 modified Gore Helex ASD occluder system

We report about our initial experience for the in 2005 modified Helex (Gore) device for closure of atrial septal defects (ASD) and persistent foramen ovale (PFO). Major changes were made at the delivery system for simplifying the Helex implantation procedure. We treated 11 patients, 8 children and 3 adults, with ages between 3 and 62 years. In 10 patients the diagnosis was a relevant ASD with volume overload of the right heart (Left to right shunts between 30 and 50%). One adult (age 58 years) have had a small left to right shunt with a PFO-like defect and the history of 2 neurologic embolic events. In 3 patients we found 2 defects. In all patients a Helex occluder was implanted successfully. The mean fluoroscopy time was 8,4 minutes. The immediate occlusion rate after 24 hours was 91%. In all cases there was a very good adaptation of the device to the anatomical structures. In this small series, the Helex occluder appears to offer a reliable system of occlusion for small and moderate ASDs and for PFO with minimal risk of major complications.

Transcatheter closure of patent foramen ovale in older adults

OBJECTIVES

Comparing results of patent foramen ovale (PFO) closure in older and younger patient cohorts.

BACKGROUND

The literature pertaining to stroke and PFO has focused on patients <55 years of age.

METHODS

Between March 2000 and December 2003, 456 consecutive stroke/transient ischemic attack (TIA) patients (14.2-91.1 years, mean 51.4 +/- 15.5) underwent successful closure of PFO with a CardioSEAL Septal Occluder by one operator at five hospitals. Of the 456 patients, 184 (40.4%) were >55 years of age at the time of the procedure (mean 66.9 +/- 8.3 years) and comprise the subject group (OLDER). The remaining 272 patients (mean 41.1 +/- 7.7) comprise the control group (YOUNGER). Data were collected prospectively in a registry type format.

RESULTS

Minor procedural complications were comparable: 7/184 (3.8%) OLDER vs. 12/272 (4.4%) YOUNGER (P = NS). In the follow-up period (1-45 months, mean = 17.8 +/- 11.1), there was no significant difference in the rate of recurrent stroke/TIA, headaches, or late unrelated death. Forty OLDER patients and 47 YOUNGER developed new onset atrial arrhythmia (P = NS). The incidence of new onset atrial fibrillation (AF), however, was significantly higher in OLDER (14/40 OLDER and only 2/47 YOUNGER, P < 0.025). All patients who were in normal sinus rhythm (NSR) before the procedure are in NSR at last follow-up.

CONCLUSIONS

Older patients should not be excluded from PFO closure. The procedure seems as safe and effective in preventing recurrent stroke in the older, as in the younger population. Older patients seem more prone to developing AF.

Septal repair implants: evaluation of magnetic resonance imaging safety at 3 T

Specialized implants are used for transcatheter closure of septal defects, including atrial and ventricular septal defects, and patent foramen ovale. These metallic devices may pose a risk to patients undergoing magnetic resonance imaging (MRI) procedures especially if performed at 3 T. Therefore, this investigation evaluated MRI safety at 3 T for septal repair implants (CardioSEAL Septal Repair Implant and STARFlex Septal Repair Implant, NMT Medical, Boston, MA, USA) by characterizing magnetic field interactions, heating and artifacts. These implants exhibited minor magnetic field interactions; heating was not excessive (+0.5 degrees C); and artifacts will only create a problem if the area of interest is in the same area as or near these devices. Thus, the findings indicated that it would be safe for a patient with these implants to undergo MRI at 3 T or lower. Importantly, because of the minor magnetic field interactions, MRI may be performed immediately after implantation.

Patent foramen ovale closure in patients with cryptogenic thrombo-embolic events using the Cardia PFO occluder

AIMS

We report our experience with three generations of the Cardia patent foramen ovale (PFO) occluder in patients with cryptogenic thrombo-embolic events (TE).

METHODS AND RESULTS

Between 1998 and 2004, interventional PFO closure was attempted in 403 patients. Prior to PFO closure, 605 TE occurred, translating into an annual incidence of 3.1%. PFO closure was successful in all patients. Peri-procedural complications occurred in eight patients (2.0%). At 6 months follow-up, residual shunt was present in 10.8% of patients. Transient thrombi developed on 10 devices (predominantly generation II) and asymptomatic wire fractures were detected in 14 cases (generation I and II). The annual incidence of recurrent TE was 2.0% (n=13). Atrial septal aneurysm and prior device-related thrombus formation were identified as predictors of recurrent TE.

CONCLUSION

Owing to technical improvements and modified adjunctive pharmacotherapy, the rate of thrombus formation has declined and wire fractures are virtually absent in generation III devices. The overall rate of recurrent TE is reduced by transcatheter PFO closure with the Cardia PFO occluder, and seems comparable to recurrence rates reported for other devices used for this purpose.