Incidence of thrombus formation on the CardioSEAL and the Amplatzer interatrial closure devices

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.

Case report: Early thrombosis in left atrial during transcatheter closure of ASD in a child with favorable outcome after use of GPIIb/IIIa receptor antagonist and heparin

Background

Acute thrombus in atrial septal defect occluders is a rare complication that requires aggressive, effective, and safe management. Tirofiban, a platelet glycoprotein IIb/IIIa receptor antagonist, is widely used for the management of thromboembolic diseases, such as coronary heart disease and stroke. To date, there is no report using the GPIIb/IIIa receptor antagonist tirofiban for the management of ASD closure-related thrombosis in children.

Case presentation

Herein, we reported a case of a 5-year-old girl with ASD who presented with acute thrombus on the left disc of the occluder device immediately after transcatheter closure of ASD. The thrombus was successfully dissolved 24 h after a combined infusion of heparin and tirofiban, followed by 1 months of aspirin and clopidogrel and 5 months of aspirin alone. No thromboembolism or hemorrhage events occurred during follow-up for more than 2 years.

Conclusion

The continuous infusion of GPIIb/IIIa receptor antagonist tirofiban combined with heparin may have beneficial effects for the management of thrombosis during ASD closure procedure.

Assessment of Device Neoendothelialization With Cardiac Computed Tomography Angiography After Transcatheter Closure of Atrial Septal Defect

Although the transcatheter closure of atrial septal defect was established as the treatment of choice several decades ago, the process of device neoendothelialization (NE) in humans is not well understood. We aimed to measure the extent of device NE using cardiac computed tomography angiography and analyze its risk factors.

Angioscopic Evaluation of Atrial Septal Defect Closure Device Neo-Endothelialization

Background

Current guidelines recommend at least 6 months of antithrombotic therapy and antibiotic prophylaxis after septal‐occluding device deployment in transcatheter closure of atrial septal defect. It has been estimated that it takes ≈6 months for complete neo‐endothelialization; however, neo‐endothelialization has not previously been assessed in vivo in humans.

Methods and Results

The neointimal coverage of septal occluder devices was evaluated 6 months after implantation in 15 patients by angioscopy from the right atrium. Each occluder surface was divided into 9 areas; the levels of endothelialization in each area were semiquantitatively assessed by 4‐point grades. Device neo‐endothelialization was sufficient in two thirds of patients, but insufficient in one third. In the comparison between patients with sufficiently endothelialized devices of average grade score ≥2 (good endothelialization group, n=10) and those with poorly endothelialized devices of average grade score <2 (poor endothelialization group, n=5), those in the poor endothelialization group had larger devices deployed (27.0 mm [25.0–31.5 mm] versus 17.0 mm [15.6–22.5 mm], respectively) and progressive right heart dilatation. The endothelialization was poorer around the central areas. Moreover, the prevalence of thrombus formation on the devices was higher in the poorly endothelialized areas than in the sufficiently endothelialized areas (Grade 0, 94.1%; Grade 1, 63.2%; Grade 2, 0%; Grade 3, 1.6%).

Conclusions

Neo‐endothelialization on the closure devices varied 6 months after implantation. Notably, poor endothelialization and thrombus attachment were observed around the central areas and on the larger devices.

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.

Neurologic complications of implantable devices

Technologies for repairing cardiac structures or sustaining cardiac function with implantable devices have helped patients with an ever-expanding array of cardiac conditions. Patients are surviving and thriving with cardiac conditions that would formerly have been disabling or fatal. With the implantation of devices in the heart, however, comes the inevitable risk of neurological complications. This chapter focuses on devices implanted in the chambers or valves of the heart itself, including prosthetic heart valves, closure devices for patent foramen ovale, atrial appendage occluder devices, short-term implantable circulatory assist devices, and long-term ventricular assist devices, but excluding coronary artery stents or extracardiac devices. Further, it considers the procedural and postprocedural risks of the devices, leaving the discussion of clinical effectiveness of the devices to other chapters of this book.

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.

A comparison of the in vivo neoendothelialization and wound healing processes of three atrial septal defect occluders used during childhood in a nonrandomized prospective trial

Objective:

We prospectively investigated the neoendothelialization of transcatheter secundum atrial septal defect (ASD) closure in children receiving one of three different occluders.

Methods:

Transcatheter ASD closure was performed for 44 children. The patients were divided into three groups: group I: Amplatzer, group II: Lifetech CeraFlex, and group III: Occlutech Figulla Flex II septal occluder. The data were prospectively analyzed. Markers of the three phases of wound healing were studied in all patients before and on the 1^st and 10^th days and 1^st month post intervention.

Results:

The mean age of children was 7.08±3.51 years, and the mean weight was 26.07±15.07 kg. The mean ASD diameter was 12.65±3.50 mm. Groups I, II, and III comprised 34.1%, 31.8%, and 34.1% patients, respectively. No significant differences were observed between the groups regarding patient number, age, defect size, device diameter, or total septum/device ratio (p>0.05). Inflammatory and proliferative phase marker levels increased following the procedure (p<0.05). However, scar formation markers did not change after 1 month. No significant differences in neoendothelializaton were observed among the different occluders (p>0.05).

Conclusion:

All three devices were composed of nitinol with different surface coating techniques. Although the different manufacturing features were claimed to facilitate of neoendothelialization, no differences were observed among the three devices 1 month following the procedure.

Successful thrombolytic treatment of a mobile thrombus on atrial septal defect occluder device

This case report presents a case with septal occluder device thrombosis which was successfully treated with low dose longer duration of thrombolytic application. Our case showed that the thrombolytic strategy with the lower dose and the longer duration might be a valuable alternative treatment option for the septal occluder thrombosis which is anticoagulation-resistant. This strategy might obviate the need for surgery.

Mid-Term Outcomes after Percutaneous Closure of the Secundum Atrial Septal Defect with the Figulla-Occlutech Device

OBJECTIVES

To evaluate the mid-term outcomes after percutaneous closure of the secundum atrial septal defects (ASD) using the Figulla-Occlutech device (FOD).

BACKGROUND

Transcatheter closure has become the method of choice for most patients with ASD. Although the FOD may have some advantageous characteristics there is a paucity of data on later outcomes after the use of this relatively new device.

METHODS

Observational, single arm study including 200 non-consecutive patients who underwent ASD closure between 04/09 and 07/15 in 2 centers. Device performance, deployment technique, and immediate and mid-term outcomes were assessed.

RESULTS

Median age and weight were 24 years (4-72) and 58 kg (15-92), respectively. Single defects were observed in 171 patients (median size of 19 mm). The remainder had multiple or multifenestrated defects. Implantation of FOD (median size of 24 mm) was successful in all (99%), but 2 patients (1 with deficient postero-inferior rim; 1 with a large ASD for the size of the child). Embolization with device retrieval occurred in 2 (1%). Median follow-up of 36 months was obtained in 172 patients. Serial echocardiographic assessment showed complete closure in all but 2 patients, in whom an additional small non-significant posterior defect was purposely left untouched. There have been no episodes of late arrhythmias, device embolization, cardiac erosion, endocarditis, thromboembolism, wire fracture, or death.

CONCLUSIONS

Transcatheter closure of ASDs in older children, adolescents, and adults using the FOD was highly successful in a wide range of anatomical scenarios with high closure rates and no complications in mid-term follow-up.

Percutaneous closure of secundum type atrial septal defects: More than 5-year follow-up

AIM: To investigate long-term efficacy of two different devices more than five years after percutaneous atrial septal defect (ASD) closure in adults.

METHODS: All patients who underwent percutaneous closure of an ASD in the St. Antonius Hospital, Nieuwegein, The Netherlands, between February 1998 and December 2006 were included. Percutaneous closure took place under general anaesthesia and transesophageal echocardiographic monitoring. Transthoracic echocardiography (TTE) was performed 24 h post-procedure to visualize the device position and to look for residual shunting using color Doppler. All complications were registered. All patients were invited for an outpatient visit and contrast TTE more than 5-years after closure. Efficacy was based on the presence of a residual right-to-left shunt (RLS), graded as minimal, moderate or severe. The presence of a residual left-to-right shunt (LRS) was diagnosed using color Doppler, and was not graded. Descriptive statistics were used for patients’ characteristics. Univariate analysis was used to identify predictors for residual shunting.

RESULTS: In total, 104 patients (mean age 45.5 ± 17.1 years) underwent percutaneous ASD closure using an Amplatzer device (ASO) in 76 patients and a Cardioseal/Starflex device (CS/SF) in 28 patients. The mean follow-up was 6.4 ± 3.4 years. Device migration occurred in 4 patients of whom two cases occurred during the index hospitalization (1 ASO, 1 CS/SF). The other 2 cases of device migration occurred during the first 6 mo of follow-up (2 CS/SF). The recurrent thrombo-embolic event rate was similar in both groups: 0.4% per follow-up year. More than 12 mo post-ASD closure and latest follow-up, new-onset supraventricular tachyarrhythmia’s occurred in 3.9% and 0% for the ASO and CS/SF group, respectively. The RLS rate at latest follow-up was 17.4% (minimal 10.9%, moderate 2.2%, severe 4.3%) and 45.5% (minimal 27.3%, moderate 18.2%, severe 0%) for the ASO- and CS/SF groups, respectively. There was no residual LRS in both groups.

CONCLUSION: Percutaneous ASD closure has good long-term safety and efficacy profiles. The residual RLS rate seems to be high more than 5 years after closure, especially in the CS/SF. Residual LRS was not observed.

Current status of percutaneous PFO closure

The clinical significance of persistent patent foramen ovale (PFO) is not well defined. Empirically, PFO has been associated with many clinical conditions. In cryptogenic stroke, migraine, and orthodeoxia/platypnea, a plausible biologic mechanism exists to support PFO closure as a possible treatment. Although transcatheter closure of PFO has been available for over 2 decades, it has remained controversial due to a paucity of evidence to guide patient and device selection. Contemporary studies investigating PFO closure as treatment for patients with these conditions have been published recently and longitudinal data regarding the safety and efficacy of the devices is now available. In this review, we aim to describe the potential clinical significance of a patent foramen in the adult, appraise the newest additions to the body of evidence, and discuss the safety, benefit, patient selection, and future of transcatheter treatment of PFO.

Thrombus formation on amplatzer septal occluder device: pinning down the cause

The use of interatrial septal occluder devices is an efficacious and less invasive alternative to open heart surgery for the repair of atrial septal defects. These devices present significant risks including thrombus formation on the device and subsequent thromboembolic events. We present a case of a woman who presented with stroke-like symptoms five years after PFO closure. The patient was subsequently found to have a thrombus on the occluder device. Our case highlights the risk of such thrombolic phenomenon and the risk associated with the device structure as a nidus for such a complication.

Echocardiographic findings in simple and complex patent foramen ovale before and after transcatheter closure

AIMS

Percutaneous closure of patent foramen ovale (PFO) in cryptogenic cerebrovascular events is an alternative to medical therapy. The interpretation of residual shunts after implantation of different devices for PFO with different morphologies is controversial.

METHODS AND RESULTS

Transcatheter PFO closure was performed in 123 patients with a history of ≥1 paradoxical embolism using three different devices: Amplatzer (n = 46), Figulla Occlutech (n = 41), and Atriasept Cardia (n = 36). Fifty-six patients presented with simple PFO and 67 patients had complex morphologies. All patients were studied with contrast enhanced transesophageal echocardiography (TEE) before interventional procedure and thereafter at 1 and 6 months and every 6-12 months in case of incomplete closure. Definite closure was confirmed in at least two consecutive TEE studies. Various PFO morphologies were identified by TEE before device implantation. The device size to PFO diameter ratio was significantly increased in patients with complex PFO compared with those patients with a simple PFO morphology (P < 0.05). The difference between the closure rate of S-PFO and C-PFO concerning each device type was significant (Amplatzer P = 0.0027, Figulla P = 0.0043, and Atriasept P < 0.01). The mean follow-up period was 3.4 years (median 2.7 years) with a cerebrovascular re-event rate of 2.4% per year. In three patients, thrombi were detected in the 6-month TEE controls and resolved after medical therapy. In three other patients, the implantation of an adjunctive device was necessary for residual shunt.

CONCLUSION

In our series of patients, the closure rate was dependent on PFO morphology more than occluder size and type. An adjunctive device was implanted in selected cases.

PFO and ASD Closure in Adulthood: Where Do We Stand?

OPINION STATEMENT

Ever since the observation was made linking a higher prevalence of a patent foramen ovale (PFO) in younger individuals with cryptogenic stroke (CS), there has been a vigorous debate as to the role the PFO plays and a search for the optimal management strategy to prevent recurrent CS. Data from observational studies from the past two decades have demonstrated the superiority of percutaneous device closure over medical therapy. The recent publication of three randomized controlled trials (RCTs), which failed to demonstrate the superiority of percutaneous closure has reignited the controversy as to how best treat these patients. In this article, we will review the contemporary literature from the past three years including the results from new meta-analyses of medical therapy and device closure. In addition, we will review the three published randomized control trials to date (ie, CLOSURE I, the PC trial, and RESPECT) along with a meta-analysis of their results. While on primary intention-to-treat analysis, the three RCTs failed to demonstrate a superiority of percutaneous PFO closure vs medical therapy, a closer look at the data seems to suggest a trend toward benefit. We come to the conclusion that the issue of optimal treatment of PFO in patients with CS is far from settled and is unlikely to be a "one size fits all" approach due to the heterogeneity of this condition. In our opinion, based on the entirety of available data, both observational and randomized, there is likely a role for percutaneous device closure in select patients with CS in whom a PFO is the likely cause of their first stroke and will remain a significant risk for recurrent neurologic events. The article will go on to review current indications for atrial septal defect (ASD) closure and will highlight safety, efficacy and caveats regarding this technique.

Amplatzer PFO occluder device may prevent recurrent stroke in patients with patent foramen ovale and cryptogenic stroke: a meta-analysis of randomised trials

OBJECTIVE

To review efficacy of percutaneous closure of patent foramen ovale compared with medical therapy in prevention of recurrent strokes in patients with cryptogenic stroke.

METHODS AND RESULTS

Electronic databases; PUBMED, EMBASE, Cochrane registry and web of knowledge were searched for relevant studies. In three randomised clinical trials involving 2303 participants, risk of the recurrent strokes (pooled HR 0.62, 95% CI=0.36-1.07, P=0.09, I(2) =10%) did not show benefit with device closure when compared with medical therapy group on meta-analysis of all three trials. However, on sensitivity analysis in trials using Amplatzer PFO occluder device, the closure of PFO was associated with significantly lower recurrent strokes (pooled HR=0.44, 95% CI=0.21-0.94, P=0.03, I(2)=0%) compared with medical therapy.

CONCLUSION

The closure of PFO with Amplatzer PFO occluder device was associated with significant reduction in recurrent strokes in patients with cryptogenic stroke and patent foramen ovale. The better outcome in prevention of secondary stroke in patients with cryptogenic stroke and PFO may be associated with type of closure device used.

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.

De novo thrombus on an atrial septal defect device 3 years after its implantation

The secundum atrial septal defect (ASD) is noted to occur in 1 per 1,500 live births and is the fourth most common congenital heart defect (CHD) [Anzai et al. in Am J Cardiol 93:426-431, 2004]. Early complications with percutaneous closure of secundum ASDs include device malposition and embolization, arrhythmias (primarily atrial fibrillation), pericardial effusion, residual shunt, and thrombus development on the left atrial disk [Chessa et al. in J Am Coll Cardiol 39:1061-1065, 2002, Co-Burn and William in Moss and Adams' Heart disease in infants, children and adolescents including fetus and young adults. Williams and Wilkins, Baltimore, 1995]. We present a patient with a very late complication of device thrombus after percutaneous secundum ASD device closure.

Closure of patent foramen ovale versus medical therapy after cryptogenic stroke

BACKGROUND

Whether closure of a patent foramen ovale is effective in the prevention of recurrent ischemic stroke in patients who have had a cryptogenic stroke is unknown. We conducted a trial to evaluate whether closure is superior to medical therapy alone in preventing recurrent ischemic stroke or early death in patients 18 to 60 years of age.

METHODS

In this prospective, multicenter, randomized, event-driven trial, we randomly assigned patients, in a 1:1 ratio, to medical therapy alone or closure of the patent foramen ovale. The primary results of the trial were analyzed when the target of 25 primary end-point events had been observed and adjudicated.

RESULTS

We enrolled 980 patients (mean age, 45.9 years) at 69 sites. The medical-therapy group received one or more antiplatelet medications (74.8%) or warfarin (25.2%). Treatment exposure between the two groups was unequal (1375 patient-years in the closure group vs. 1184 patient-years in the medical-therapy group, P=0.009) owing to a higher dropout rate in the medical-therapy group. In the intention-to-treat cohort, 9 patients in the closure group and 16 in the medical-therapy group had a recurrence of stroke (hazard ratio with closure, 0.49; 95% confidence interval [CI], 0.22 to 1.11; P=0.08). The between-group difference in the rate of recurrent stroke was significant in the prespecified per-protocol cohort (6 events in the closure group vs. 14 events in the medical-therapy group; hazard ratio, 0.37; 95% CI, 0.14 to 0.96; P=0.03) and in the as-treated cohort (5 events vs. 16 events; hazard ratio, 0.27; 95% CI, 0.10 to 0.75; P=0.007). Serious adverse events occurred in 23.0% of the patients in the closure group and in 21.6% in the medical-therapy group (P=0.65). Procedure-related or device-related serious adverse events occurred in 21 of 499 patients in the closure group (4.2%), but the rate of atrial fibrillation or device thrombus was not increased.

CONCLUSIONS

In the primary intention-to-treat analysis, there was no significant benefit associated with closure of a patent foramen ovale in adults who had had a cryptogenic ischemic stroke. However, closure was superior to medical therapy alone in the prespecified per-protocol and as-treated analyses, with a low rate of associated risks. (Funded by St. Jude Medical; RESPECT ClinicalTrials.gov number, NCT00465270.).

Atrial septum defect closure device in a beating heart, from the perspective of a researcher in artificial organs

Transcatheter closure of atrial septum defect (ASD) with a closure device is increasing, but the history of clinical use of this procedure is still short, and the efficacy and long-term safety remain unproved. The total number of closure devices implanted throughout the world has not been counted accurately. Therefore, the probability of complications occurring after implantation is uncertain. Device-related complications that occur suddenly late after implantation are life-threatening, and quite often necessitate emergency surgical intervention. In Japanese medical journals, authors reporting closure devices have mentioned no complications and problems in their facilities. Detailed studies of device-related complications and device removal have not been reported in Japan. In fact, this literature search found an unexpectedly large number of reports of various adverse events from many overseas countries. When follow-up duration is short and the number of patients is small, the incidence of complications cannot be determined. Rare complications may emerge in a large series with a long observation period. Consequently, the actual number of incidents related to ASD closure devices is possibly several times higher than the number reported. Guidelines for long-term patient management for patients with an implanted closure device are necessary and post-marketing surveillance is appropriate. Development of a national database, a worldwide registration system, and continuous information disclosure will improve the quality of treatment. The devices currently available are not ideal in view of reports of late complications requiring urgent surgery and the need for life-long follow-up. An ideal device should be free from complications during life, and reliability is indispensable.

PFO closuRE and CryptogenIc StrokE (PRECISE) registry: a multi-center, international registry

BACKGROUND

The Premere™ PFO closure device has a special design for closure of patent foramen ovale (PFO) including a flexible distance and angulation between the right and left disc providing minimal septal distortion. The primary objective of the study was to determine the degree of risk for stroke or transient ischemic attack (TIA) in patients after Premere™ PFO closure device implantation.

METHODS

In this multicenter, prospective observational registry, patients with a clinical indication for PFO closure were included. Patients had a history of stroke or TIA with right to left shunt. Follow-up visits were scheduled according to routine clinical practice.

RESULTS

In 23 centers from 10 countries, 267 patients with successful device implantation were included. Assessment of right to left shunt after device implantation revealed no residual shunt in 71 %, small shunts in 16.8 %, and moderate or large residual shunts in 5.6 and 6.5 %. With common clinical practice, use of Coumadin or heparin decreased from 27 % pre- to 3 % post-implantation, while use of acetylsalicylic acid or thienopyridines increased from 64 to 95 % and 27 to 80 %, respectively; 18 % of patients were discharged with anti-platelet monotherapy. Mean follow-up was 11 ± 9 months (range 1-24 months). There was no stroke or TIA. During follow-up, there was one sudden death. Atrial fibrillation occurred in five (1.9 %) patients. One (0.4 %) patient with a thrombophilic diathesis developed a thrombus.

CONCLUSIONS

In this prospective, international, multicenter PRECISE registry, the use of the Premere™ PFO closure device for closure of PFO after stroke or TIA resulted in good clinical results with no recurrent event.

Thrombus formation after left atrial appendage exclusion using an Amplatzer cardiac plug device

The feasibility and safety of left atrial appendage closure with the Amplatzer cardiac plug (AGA Medical Corp., Minneapolis, MN) have been recently published; no thrombus formation on the device surface has been reported previously. We describe a case of a 66-year-old man with permanent atrial fibrillation, previous stroke, and contraindication for long-term oral anticoagulant therapy. A 22-mm ACP device was deployed successfully without complications. The patient was discharged on acetyl salicylic acid 100 mg and clopidogrel 75 mg daily. After 4 weeks, the patient was admitted for a lower gastrointestinal bleeding and clopidogrel was stopped. A 3-month follow-up echocardiogram confirmed the exclusion of the LAA but it demonstrated the presence of a thrombus on the atrial surface of the device. It was decided to keep the patient on acetyl salicylic acid 100 mg with the addition of enoxaparin 60 mg bid. Transesophageal echocardiogram demonstrated total resolution of the thrombus after 2 months.

Stroke due to late device thrombosis following successful percutaneous patent foramen ovale closure

We report a case of stroke due to device thrombosis occurring three years following percutaneous patent foramen ovale (patent foramen ovale) closure with an Amplatzer atrial septal occluder device. We discuss risk factors that may have contributed to device thrombosis and raise concerns regarding the lack of a dedicated PFO closure device for clinical use in the United States.

Intermediate and long-term followup of percutaneous device closure of fossa ovalis atrial septal defect by the Amplatzer septal occluder in a cohort of 529 patients

Objectives:

The aim of present study is to analyze the intermediate and long-term follow up results of percutaneous closure of fossa ovalis atrial septal defect (ASD) with Amplatzer septal occluder (ASO) in a large cohort of patients including children and adults.

Methods:

Between May 1998 and July 2008, 529 patients (age group 2-77 years, median 28 years) underwent successful device closure with an ASO at single tertiary referral cardiac center in India.. This was out of an attempted 543 cases. The procedure was carried out in catheterization laboratory under transesophageal echocardiographic and fluoroscopy guidance. The mean size of ASD was 20 mm (7-40 mm) while size of septal occluder was 10-40 mm (mean 24 mm). Two devices were deployed in four patients. Three patients developed transitory pulmonary edema in immediate postprocedure period requiring ICU care for 48 hrs. All patients were advised for Aspirin (3-5 mg/kg, maximum 150 mg) once daily for 6 months. In patients with device 30 mm or larger, Clopidogril ( 75 mg once daily) was given for 3 months in addition to Aspirin. Clinical evaluation, echocardiogram were done on 3 months, 6 months and then at 1, 3, 5, 7 and 10 years of follow up. Transesophageal echocardiography (TEE) was performed in case of any doubt on clinical evaluation or on transthoracic echocardiography (n=10).

Results:

Followup data is available for 496 patients (93.7%). Followup period is from 12 months to 120 months (median 56 months). On followup, device was in position in all patients, no residual shunt and no evidence of thrombosis. Interventricular septal motion normalized on day of procedure in 89% patients, in 6% over 3 months while flat septal motion persisted in 5% (n=25, all in age group > 40 years) of cases, though right ventricular dilatation persisted in 10% (n=50, age more than 40 years) of patients. Symptom-free survival was 96.7 % (480/496) in patients who came for followup. Only one 68 year old patient with preexistent tricuspid regurgitation developed congestive heart failure, and one patient (58 years old) had a history of hemiparesis after 1 year of device on telephonic interview. Ten patients were in atrial fibrillation (AF) before the procedure and remained in AF on followup.

Conclusions:

Our study showed that percutaneous closure of fossa ovalis ASD is a safe and effective procedure on intermediate and long-term followup in both the children as well as adults.both. Technical factors during the procedure and proper follow up are important. Our single centre intermediate and long term experience in a large number of patients support the use of device closure as an alternative to surgery.

Experimental study of the Spider™ patent foramen ovale occluder

AIM

To evaluate the feasibility, safety and efficacy of the Spider™ patent foramen ovale (PFO) occluder for the treatment of PFOs in an animal model.

METHOD

The foramen ovale was punctured to establish an animal model of a PFO. Under fluoroscopic guidance, the PFO was occluded with the Spider PFO occluder. The piglets were electively sacrificed at months 1, 2, 3, 6 and 12 after occlusion for macroscopic and microscopic examination.

RESULTS

PFOs were successfully created and occluded percutaneously in 20 piglets. All piglets recovered from the procedure in good condition and completed follow-up. Macroscopic examination of all hearts showed complete closure of the PFO. The position of each device was correct. All devices were completely covered and embedded in pale and smooth tissue. There was no evidence of interference with adjacent structures of the heart or valves. The occluder was partially covered by endocardium after 1 month, almost completely covered by fresh endocardium after 3 months, and embedded within thick fibrous tissues and fresh vessels after 6 months. The tissue covering both occluder discs demonstrated some infiltration of inflammatory cells, including patches of lymphocyte aggregation. This inflammatory cell reaction diminished with increasing distance from the device. Furthermore, the number of inflammatory cells decreased gradually during follow-up and eventually, at 6-month follow-up, the inflammatory response was no longer visible. The 12-month histological findings did not differ from the 6-month findings.

CONCLUSION

Transcatheter closure of PFO with the Spider PFO occluder is effective and safe in an animal model. These results support further investigation of this device in animals and, if the results are confirmed, in human clinical trials.

A new pan-nitinol occluder for transcatheter closure of ventricular septal defects in a canine model

BACKGROUND

The Amplatzer ventricular septal defect (VSD) occluder has a fixed stainless steel pin bottom protruding out of the surface at the center of the discs on both sides. Theoretically, this protruding bottom may interfere with epithelialization or, in some cases, cause thrombosis.

OBJECTIVE

To evaluate a new type of pan-nitinol VSD occluder without the protruding stainless steel pin bottom on both sides in a canine VSD model designed to ensure safety, effectiveness, and feasibility.

METHODS AND RESULTS

VSDs were successfully created by transseptal ventricular septal puncture with a Brockenbrough needle and dilation with an 8-mm-diameter balloon via the right jugular vein in 9 out of 12 canines. The new type VSD occluder was successfully implanted in 8 of the 9 modeled canines. No procedure- or device-related complication was observed. Transthoracic echocardiography and MRI 2 months after device implantations showed that there was no device dislocation or heart valve dysfunction in 6 of the 8 tested canines. In addition, gross and pathological examinations 3-6 months after implantation showed no corrosion of the devices or serious inflammatory reactions in the modeled animals. Complete endothelialization was seen over the surface of the discs.

CONCLUSIONS

The new pan-nitinol VSD device can be successfully implanted in a canine VSD model via a transcatheter approach featuring high success rate, low risk of procedure-related complications, and sound biocompatibility. The result suggests that this new VSD occluder could be used safely in future clinical trials for further test.