Percutaneous closure of secundum atrial septal defect with a new self centering device ("angel wings")

Preliminary Experience With the New Amplatzer™ Trevisio™ Delivery System in Transcatheter Atrial Septal Defect Closures in Children

Objectives: To evaluate safety, efficacy, and technical advantages of Amplatzer™ Trevisio™ intravascular delivery system (ATIDS) in percutaneous atrial septal defect (ASD) closure in children. Background: The Trevisio™ is a novel delivery system designed for accurate and facilitated implantation of Amplatzer™ devices. There are no published clinical reports so far. Methods: During September 2020, 9 children with anatomically challenging ASDs underwent attempted transcatheter closure using ATIDS to deliver Amplatzer™ Septal occluders (ASO). All interventions were performed under general anesthesia, trans-esophageal echocardiography (TOE), and fluoroscopic guidance. Standard safety, immediate, and 60-days outcomes were prospectively assessed. Results: The median age was 8.1 (5.1-16.9) years and the median bodyweight was 30 (18-63) kg. Six patients had isolated secundum-type ASDs with absent anterosuperior rims including one with an aneurysmal septum. Three patients had unclassical defects associated with complex congenital heart anomalies. Eight devices were delivered from the femoral vein and the jugular vein was accessed in one patient with interrupted inferior caval vein and azygos continuation. All implantations were successful. The shape, position, and orientation of the ASO were identical before and after release on TOE and fluoroscopy. There was no device embolization or serious complication following closure. Complete shunt closure was confirmed on follow-up. Conclusions: We report the first clinical experience with ATIDS in transcatheter ASD pediatric closures. Safety and efficacy were witnessed in our case-series. The major advantage of reduced-tension deployment and reliable precision in device positioning is highly beneficial in challenging anatomies and unusual access.

Outcomes of Device Closure of Atrial Septal Defects

Several devices have been designed and tried over the years to percutaneously close atrial septal defects (ASDs). Most of the devices were first experimented in animal models with subsequent clinical testing in human subjects. Some devices were discontinued or withdrawn from further clinical use for varied reasons and other devices received Food and Drug Administration (FDA) approval with consequent continued usage. The outcomes of both discontinued and currently used devices was presented in some detail. The results of device implantation are generally good when appropriate care and precautions are undertaken. At this time, Amplatzer Septal Occluder is most frequently utilized device for occlusion of secundum ASD around the world.

Antithrombotic Therapy for Percutaneous Cardiovascular Interventions: From Coronary Artery Disease to Structural Heart Interventions

Percutaneous cardiovascular interventions have changed dramatically in recent years, and the impetus given by the rapid implementation of novel techniques and devices have been mirrored by a refinement of antithrombotic strategies for secondary prevention, which have been supported by a significant burden of evidence from clinical studies. In the current manuscript, we aim to provide a comprehensive, yet pragmatic, revision of the current available evidence regarding antithrombotic strategies in the domain of percutaneous cardiovascular interventions. We revise the evidence regarding antithrombotic therapy for secondary prevention in coronary artery disease and stent implantation, the complex interrelation between antiplatelet and anticoagulant therapy in patients undergoing percutaneous coronary intervention with concomitant atrial fibrillation, and finally focus on the novel developments in the secondary prevention after structural heart disease intervention. A special focus on treatment individualization is included to emphasize risk and benefits of each therapeutic strategy.

Antiplatelet therapy in valvular and structural heart disease interventions

Transcatheter interventions for valvular and structural heart diseases are rapidly expanding due to greater operators' experience and development of new generation devices associated with increased procedural safety. They represent the standard strategy for patients with prohibitive risk for open surgery. These procedures are associated with a significant occurrence of both thrombotic and bleeding complications, thus in this setting, even more than in other percutaneous procedures, the balance between thrombotic and bleeding risk is critical. This review describes the current data available on the antithrombotic management of patients undergoing transcatheter aortic valve implantation (TAVI), percutaneous mitral valve repair with the MitraClip system, percutaneous left atrial appendage occlusion and percutaneous patent foramen ovale (PFO)/atrial septal defects (ASD) closure.

[Interventional closure of atrial septal defects, patent oval foramen and ventricular septal defects]

Percutaneous transcatheter closure techniques and devices for congenital intracardiac shunts have considerably improved; therefore, catheter closure is now the treatment of choice for atrial septal defects (ASD). This is technically feasible in more than 80% of patients with a secundum ASD and the success rate is higher than 99%. General anesthesia is as a rule unnecessary and the hospital stay is very short. A patent oval foramen (POF) is a potential cause of cryptogenic stroke and peripheral embolisms. The catheter occlusion has many advantages in comparison to lifelong anticoagulation therapy and for some patients it is the only therapeutic option. Randomized trials have shown that interventional closure leads to results which are comparable to drug therapy and for some occlusion systems even evidence of significant advantages compared to drug therapy was found. Even ventricular septal defects (VSD), including perimembraneous and post-myocardial infarction VSDs can be closed by catheter techniques with a high success rate.

Transcatheter closure of atrial septal defects

Transcatheter closure of atrial septal defects has evolved significantly over the last 20 years. Transcatheter closure has replaced surgical closure for the treatment of most secundum atrial septal defectsat the current time. A major reason for this is the lower morbidity of transcatheter closure procedures. Several closure devices have come into clinical use. The Amplatzer septal occluder (AGA Medical Co.) currently has the largest reported experience and subsequently the best-established safety and efficacy features. Clinically challenging situations, such as larger atrial septal defects, atrial septal defects with deficient rims and multiple atrial septal defects, are increasingly being addressed using the transcatheter approach, with improved results. The incidence of most complications has significantly reduced over time, and serious side effects are relatively uncommon. In this review, the literature is summarized regarding the current role of transcatheter closure, the evolution of the different available devices for clinical use and the complications that occur with their use. A comparison is also made with surgical closure techniques.

Shaping tissue with shape memory materials

After being severely and quasi-plastically deformed, shape memory materials are able to return to their original shape at the presence of the right stimulus. After a brief presentation about the fundamentals, including various shape memory effects, working mechanisms, and typical shape memory materials for biomedical applications, we summarize some major applications in shaping tissue with shape memory materials. The focus is on some most recent development. Outlook is also discussed at the end of this paper.

[Rapidly evolving techniques for structural heart disease interventions]

Structural heart disease interventions are the transcatheter techniques used for treating non-coronary heart disease. In recent years, these techniques have generated considerable interest even though they still comprise only a small percentage of the total volume of interventions performed in interventional cardiology departments. The level of interest in these techniques is high probably because their application is characterized by a number of special features: a) the need for multidisciplinary teams; b) the need for specialized education and training; c) the requirement for special skills developed through education and experience, and d) the limited number of referral centers at present. This article describes four specific techniques: a) percutaneous closure of perivalvular leaks; b) percutaneous left atrial appendage obliteration; c) percutaneous treatment of mitral regurgitation, and d) transcatheter implantation of prosthetic aortic valves. We explore the rationale for using the technique, the specific procedures involved and the results obtained.

Pre-procedural planning for percutaneous atrial septal defect closure: transesophageal echocardiography compared with cardiac computed tomographic angiography

BACKGROUND

The safety and efficacy of percutaneous closure of atrial septal defects (ASDs) is determined by several variables, including defect size, presence of adequate rim tissue, relationship to other cardiac structures, and associated congenital anomalies.

OBJECTIVE

We sought to determine the accuracy of computed tomographic angiography (CTA) in predicting a defect's size compared with pre-procedural transesophageal echocardiography (TEE) and to the current "gold standard" balloon sizing by intracardiac echocardiography (ICE).

METHODS

Thirty-five consecutive patients referred for possible percutaneous closure of suspected secundum ASD were evaluated with gated multislice CTA after initial TEE screening. Axial and sagittal image planes of the ASD from the CTA multiplanar reformation (MPR) images were used to measure the defect size and surface area.

RESULTS

Of the 35 patients with secundum-type ASDs, 5 subjects had disqualifying anatomy by CTA and 2 had an unsuccessful closure, resulting in a procedural success rate of 93%. Measurement of defect area by gated MPR images provided the strongest correlate to ICE balloon size. In large ASDs, TEE was less well correlated to the maximum defect size and identification of the inferior/inferoposterior rims than CTA.

CONCLUSIONS

Cardiac CTA is an accurate and useful technique for pre-procedural assessment of ASDs and may be superior to conventional TEE in large defects that have deficient inferior rims.

Pediatric cardiac interventions

The field of pediatric cardiac interventions has witnessed a dramatic increase in the number and type of procedures performed. We review the most common procedures performed in the catheter laboratory. Lesions are divided according to their physiological characteristics into left-to-right shunting lesions (atrial septal defect, patent ductus arteriosus, ventricular septal defect), right-to-left shunting lesions (pulmonary stenosis, pulmonary atresia/intact ventricular septum), right heart obstructive lesions (peripheral arterial pulmonic stenosis, right ventricular outflow tract obstruction), and left heart obstructive lesions (aortic valve stenosis, coarctation of the aorta). In addition, a miscellaneous group of lesions is discussed.

Progression to late complete atrioventricular block following amplatzer device closure of atrial septal defect in a child

Atrial septal defect (ASD) closure by interventional catheterization techniques has been widely accepted and is considered a standard treatment for this congenital heart defect. We report the case of a 6-year-old girl who presented with progression of first-degree atrio-ventricular (AV) block to symptomatic, complete heart block after ASD closure with an Amplatzer septal occluder (ASO). Although she received steroids immediately after the procedure when second-degree AV block was seen, her AV conduction slowly deteriorated over 4 years, requiring permanent pacemaker implantation. We can only speculate that the injury to the conduction system was the result of persistent trauma, ischemia, or progressive scarring caused by the ASO on the AV nodal region. It is uncertain if early device removal would have prevented this complication. This case highlights the importance of cardiac rhythm monitoring following ASO implantation for ASD closure on long-term follow-up.

Single pediatric center experience with multiple device implantation for complex secundum atrial septal defects

OBJECTIVES

We analyzed the efficacy and complications of placing multiple transcatheter devices to correct complex ASD in a primarily pediatric population.

BACKGROUND

Limited pediatric information exists regarding the safety and efficacy of using multiple devices for secundum atrial septal defects (ASD) when multiple defects are present.

METHODS

Cath lab, echo, and clinical data were reviewed for 238 patients who underwent device closure of secundum ASD from 2000 to 2007 at a single pediatric center. Of those requiring multiple devices (n = 15), residual shunting and complications were assessed.

RESULTS

238 patients (mean age 12 yrs; 80% < 16 yrs) underwent transcatheter ASD closure. 34 (14%) had multiple ASD, but only 15 received multiple devices (2 devices in 14 and 3 devices in 1). The mean age and weight (12 yrs; 35 kg) represent a younger population than previously reported. Only 3 were > 15 yrs, with a median age of 10.8 yrs (range 2-31). There was no compromise or obstruction to surrounding structures, and no device embolization or erosion was noted. A tiny thrombus was observed on the right sided screw of one device with no clinical sequelae. One patient (age 31 yrs) died at home 30 days post procedure from cardiac tamponade. Autopsy revealed the 3 intact devices in stable position without evidence of erosion. Latest available echo follow-up for the group revealed functional resolution of atrial level shunting in all patients.

CONCLUSION

Multiple devices can safely and effectively be implanted in the pediatric population to close complex ASD.

Atrial Septal Defect and Atrial Fibrillation: The Known and Unknown

Atrial fibrillation (AF) is a common complication in patients with atrial septal defects (ASDs). The link between AF and ASD is fairly complex and entails modifications in electrophysiologic, contractile and structural properties, at the cellular and tissue level, of both atria, mainly due to chronic atrial stretch and dilation. Surgical repair or percutaneous closure of ASDs are equally effective in reducing mortality and symptoms but limited in preventing or curbing AF, unless combined with an arrhythmia-specific procedure. Transesophageal echocardiography (TEE) and intracardiac echocardiography (ICE) have improved the safety and success of the above procedures. Finally, clearer understanding of the pathophysiology of AF in patients with ASD (and CHF, in general) has led to target-specific advances in medical management.

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.

Transcatheter closure of secundum atrial septal defects in adults with the Amplatzer septal occluder: Intermediate and long-term results

AIMS

Transcatheter closure of secundum atrial septal defects (ASD) with the Amplatzer septal occluder (ASO) has become a standard procedure in most pediatric and adult patients. However, data addressing success rates and outcome in adults is limited. We sought to define the safety profile of the ASO in the community setting and identify the percentage of adults with ASD amenable to percutaneous closure with the ASO.

METHODS

We performed a retrospective analysis of patients' records referred for transcatheter ASD closure from 1999 through 2005 at a single institution. Patients were evaluated with right heart catheterization and underwent closure of the ASD according to standard indications under transesophageal and fluoroscopic guidance.

RESULTS

Two hundred and seven consecutive patients were taken to the catheterization laboratory for hemodynamic evaluation and possible interventional closure of an ASD. Of those patients, 18 were excluded because the defect and the left-to-right shunt were hemodynamically insignificant (n = 7) or because there was no distinct defect, but instead a multi-perforated septum (n = 11). Nineteen cases were excluded for anatomic reasons. Of the remaining 170 patients, ASO implantation was attempted and successfully performed in 166 (83% of 200 patients with hemodynamically significant ASD). Complications occurred in 11 cases (6.5%) (device dislocation = 4, transient ST-segment elevation = 4, TIA = 1, hemoptysis = 1, pericardial effusion = 1); none of these events were associated with long-term sequelae. During a median follow-up period of 13 months (range 6-80) there were no major clinical events.

CONCLUSIONS

More than 80% of adults with a distinct, hemodynamically significant secundum ASD can be successfully treated with the ASO. The immediate success rates are excellent and follow-up data suggest that the ASO is a safe device well suited for transcatheter ASD closure.

Multiple Amplatzer septal occluder devices for multiple atrial communications: Immediate and long-term follow-up results

OBJECTIVES

We report on the feasibility, effectiveness, and long-term outcome of transcatheter closure of multiple ASD's using multiple ASO devices.

BACKGROUND

Little is known about the use and long-term outcome of multiple Amplatzer Septal Occluder (ASO) devices to close multiple atrial septal defects (ASD's).

METHODS

From May 1997 to June 2006, 33 patients (mean age 38.9 years and mean weight 68 kg) underwent transcatheter closure of multiple ASD's under transesophageal (TEE) or intracardiac echocardiographic (ICE) guidance.

RESULTS

Unless not available, the device size chosen to be deployed was +/-2 mm larger than the stretched diameter or no more than 30-40% larger than the ICE/TEE 2D diameter. Sixty-seven devices were deployed in 33 patients. The mean diameters of the larger and smaller defects were 12.9 and 7.7 mm, and the corresponding mean balloon stretched diameters were 19.2 and 12.0 mm, respectively. The mean larger and smaller device diameters were 19.0 and 13.4 mm, respectively. The mean QP: Qs ratio was 1.8:1. The mean fluoroscopy time, and procedure time were 16.4 and 81.6 min respectively. Immediately after the procedure 15 patients had complete closure, 8 had trivial shunt, 9 had small shunt and one had large shunt. Complications included a device embolization within 24 hr and left atrial-aortic wall erosion and pericardial effusion at 2 years. The mean follow-up interval was 34.8+25.7 months.

CONCLUSIONS

Device closure of multiple ASD's using multiple ASO's is safe and effective. Continued follow-up is important to assess the long-term outcome.

Device closure of large atrial septal defects: technical considerations

Transcatheter closure of secundum type atrial septal defect has become an accepted alternative to surgical closure. Closure of small to moderate-sized atrial septal defects is technically easy and straightforward, however, closure of large atrial septal defects may be technically challenging. We review the available techniques that can be used to secure deployment of the device in good position. These techniques include the use of a specially designed delivery sheath, the 'Hausdorf sheath', or deployment of the device in either right or left pulmonary veins, the use of a dilator or balloon to hold the left disk in the left atrium and the use of a Judkins right coronary guiding catheter to deploy the device.

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.

Aortic sinus-left atrial fistula after interventional closure of atrial septal defect

A 3-year-old boy underwent interventional closure of an atrial septal defect using an Amplatzer septal occluder. After 4 weeks, an aortic sinus-to-left atrial fistula was detected by echocardiography in an asymptomatic child. The device was surgically explanted with fistula and atrial septal defect closure. Follow-up was uneventful.

Do complaints of amaurosis fugax and blurred vision after transcatheter device closure of atrial septal defect indicate microemboli to retinal vessels?

Atrial septal defect (ASD) is a common diagnosis in adults undergoing surgical repair. The aim of the study was to determine if ocular symptoms following treatment are due to microemboli. The study group included 20 adult patients (9 men, 11 women, mean age 57.2 years) with ASD who had undergone successful closure with the Amplatzer occluder. Patients were treated with aspirin or warfarin during the 6 months after the procedure. All were evaluated neurologically and an ocular medical history was obtained. Ocular examination included the 120-point Humphery visual field. Transcranial Doppler (TCD) was performed to monitor the middle cerebral artery. Two patients complained of amaurosis fugax at 1 and 3 months after the procedure, and two patients complained of blurred vision at 3 and 4 months after the procedure. TCD performed within 24 h of the complaints revealed no abnormalities. In all patients, the neurological and ocular examinations, including the visual field test, were normal. In conclusion, microembolic events do not appear to be the cause of the ocular complaints in patients with ASD treated with Amplatzer occluder. Further studies in larger samples are needed to confirm these results.

Do Complaints of Amaurosis Fugax and Blurred Vision after Transcatheter Device Closure of Atrial Septal Defect Indicate Microemboli to Retinal Vessels?

Atrial septal defect (ASD) is a common diagnosis in young adults with congenital heart disease. The aim of this study was to determine if ocular symptoms following percutaneous treatment are due to microemboli. The study group included 20 adult patients (9 men, 11 women, mean age 57.2 years) with ASD who had undergone successful closure with the Amplatzer occluder. The patients were treated with aspirin or warfarin during 6 months after the procedure. All were evaluated neurologically and an ocular medical history was obtained. Ocular examination included the 120-point Humphrey visual field. Transcranial Doppler (TCD) was performed to monitor the middle cerebral artery. Two patients complained of amaurosis fugax at 1 and 3 months after the procedure, and two patients complained of blurred vision at 3 and 4 months after the procedure. TCD performed for 45 minutes within 24 hours of the visual complaints revealed no abnormalities. In all patients, the neurological and ocular examinations, including the visual field test, were normal. In conclusion, microembolic events could not be demonstrated to be the cause of the ocular complaints in patients with ASD treated with Amplatzer occluder. Further studies in larger samples are needed to confirm these results.

Reversible atrioventricular block associated with closure of atrial septal defects using the Amplatzer device

OBJECTIVES

We sought to determine the incidence, nature, and predisposing factors of atrioventricular block (AVB) associated with closure of atrial septal defects (ASDs) using the Amplatzer septal occluder (ASO).

BACKGROUND

In our institution, 162 patients underwent ASD closure using ASO between December 1997 and December 2001. This includes small children with large defects.

METHODS

Electrocardiographic tracings during ASO implantation and at follow-up visits were reviewed. Anatomic characteristics and device size were assessed as potential risk factors for AVB.

RESULTS

Ten patients (6.2%) presented with new-onset (n = 9) or aggravation of preexisting (n = 1) AVB. Atrioventricular block occurred during the procedure (n = 3) or was first noted one day to one week later (n = 7). Patients had first-degree (n = 4), second-degree Wenckebach (n = 4), or third-degree (n = 2) AVB, with no symptoms or hemodynamic compromise. First-degree AVB persisted in two patients at 12 and 33 months of follow-up, whereas most recovered normal AV conduction within one (n = 7) or six months (n = 1). A larger shunt (Qp/Qs ratio 2.8 +/- 0.9 vs. 2.1 +/- 0.8, p < 0.01) and device size (24 +/- 5 vs. 19 +/- 6 mm, p < 0.01) were the only determinant factors for AVB. A device size > or =19 mm was used in 90% (9 of 10) of patients who developed AVB, as compared with 49% of those without AVB (p < 0.02).

CONCLUSIONS

Closure of ASDs using the large ASO can be associated with the development of AV block and mandate a closer follow-up. In our series, however, all AVBs resolved or improved spontaneously, with no recurrence at mid-term follow-up.

Five-year clinical and echocardiographic evaluation of the Das AngelWings atrial septal occluder

BACKGROUND

The late outcome of patients treated with atrial septal occluder devices remains incompletely defined. The purpose of this study was to assess the late outcome (range 4-7 years postprocedure) of patients in whom the Das AngelWings septal occluder device was implanted in the atrial septum. We report the clinical and echocardiographic outcome, at an average of 5 years following the procedure, of patients treated with the Das AngelWings device used to close either a secundum atrial septal defect (ASD) or a patent foramen ovale (PFO).

METHODS

Thirty-two patients underwent successful percutaneous closure of an atrial septal closure, patent foramen ovale, or fenestration in the lateral tunnel of their Fontan with the Das AngelWings device between June 1995 and March 1998 at Duke University Medical Center. Two of the 32 patients were lost to follow-up. The remaining 30 patients were divided into 3 groups based on indication for device implantation. Group 1 consisted of 14 patients with a secundum ASD and predominantly left-to-right atrial shunting. Group 2 consisted of 8 patients who had a PFO and who suffered a thromboembolic event. Group 3 (compassionate use) consisted of 10 patients with multiple comorbid medical problems with predominantly right-to-left shunting at the atrial level causing hypoxemia. Eight of the patients in group 3 were severely ill at the time of device implantation. The 2 remaining patients in group 3 underwent AngelWings implantation for closure of right-to-left shunting through a Fontan fenestration. Mean follow-up was 59 months.

RESULTS

There was no device embolization. No patient in the ASD or PFO/stroke group had a clinical complication. By radiographic examination, 2 of 27 patients had evidence of fracture of the nitinol framework at 2-year follow-up. Residual shunting was present in 44% at 24 hours, 20% at 1 year, and 18.8% at 2 years by use of Doppler color flow imaging and/or microcavitation echocardiographic studies. Mild mitral regurgitation caused by the AngelWings device occurred in 1 patient. One patient in the compassionate use group had a subsequent neurologic event. Five of the 10 patients in the compassionate use group died of comorbid illnesses in follow-up, none directly related to device complications.

CONCLUSION

The late clinical outcome of secundum ASD and PFO/stroke patients in this study demonstrates that Das AngelWings closure of the atrial septum is effective and safe. These data are encouraging with respect to the expanding use of other percutaneously implanted ASD occlusion devices, although late clinical safety and efficacy data are needed for the specific devices being implanted.

Catheter Closure of Secundum ASD Using “Other” Devices

The first nonoperative ASD closure was performed by Noel L. Mills and Terry D. King in a 17-year old female patient on April 8, 1975. In the following years there was little interest in this clinical field after trials with the "Clamshell Device" had been discontinued because of arm fractures. From the late 1980s until the mid 1990s E. B. Sideris ("Buttoned Device") and U.U. Babic ("ASDOS") kept the ideas of King & Mills alive while G.S. Das developed the first self-centering device ("AngelWings"). Clinical trials with ASDOS and AngelWings have been stopped because of complicated technology and risk of perforation. The Buttoned Device and its modifications are still used with high success rates even in defects > 20 mm and low long-term risk of perforation. Since the pioneering works of King & Mills marked improvements in devices and delivery systems have been achieved. After almost three decades of ongoing research and development, transcatheter ASD closure has become a clinical routine procedure.

ASD Closure with the Amplatzer Device

We report the safety and efficacy of the Amplatzer device for transcatheter closure of ASD and fenestrated Fontan in children and adults. One hundred and two patients underwent transcatheter occlusion of the defect. The median age of the patients was 18.2 years, the median size of the ASDs by TEE was 17.6 mm, the median balloon-stretched diameter was 19.9 mm, and the median size of the device implanted was 20 mm. Immediately after the release of the device, color Doppler echocardiography revealed no residual shunt in 92 (90.19%) of 102 patients. At 24 hours all the patients 101/101 (100%) had complete closure. The minor complications encountered after the procedure were atrial arrhythmias in 4 patients. The only major complication we had was a baby who died. In conclusion, the ASO device is a safe and effective device for catheter closure of most secundum ASDs and fenestrated Fontan.

The gold standard for atrial septal defect closure: current surgical results, with an emphasis on morbidity

Device closure of atrial septal defects (ASDs) is rapidly becoming routine in children. Comparisons are often made to older surgical series with higher morbidities. However outcomes including reintervention, late failure, and the need for long-term follow-up must be considered and compared to those of a current surgical series. One hundred consecutive surgical closures of ASDs in children were reviewed. The mean age was 60.5 +/- 6.4 months; 6 patients underwent repair in the first year of life. Full clinical and echocardiographic follow-up was available on all patients. There was no mortality; there were no residual ASDs and no neurological complications. There were 3 cases of postpericardiotomy syndrome and 26 pericardial effusions. Median stay was 4 days; all patients have been discharged from follow-up. A review of the literature on the short-term follow-up of ASD devices revealed a number of problems. Their long-term durability is unknown. As such, it remains an experimental procedure and must be compared over the long-term to the current gold standard, surgical repair.

The use of anticoagulation in pediatric cardiac disease

Palliation and repair of increasingly complex congenital heart defects as well as the emergence of novel contexts has led to multiple scenarios in which a real or potential risk of thromboembolism may exist. While various anticoagulation methodologies have been well defined for adults, there are few studies relating directly to pediatric patients. This article reviews a number of specific pediatric disease states, the representative pediatric literature, and, where appropriate, the corresponding adult literature. In so doing, the art and science of pediatric cardiac anticoagulation is defined with the hope to engender further thought regarding future directions of study and therapy.

Role of intracardiac echocardiography in atrial septal abnormalities

The purpose of this review is to outline the feasibility of performing a comprehensive atrial septal examination from the internal confine of the right atrium and to evaluate the advantages resulting by intracardiac echocardiography (ICE) evaluation of atrial septal morphology as well as pathophysiology. In this setting, ICE indications have not yet been established because ICE is a relatively new technique that is still evolving. Notwithstanding, during catheter-based secundum atrial septal defect and patent foramen ovale closure, ICE seems useful for diagnosing cardiac abnormalities instantly, guiding and monitoring all stages of the procedures, and assessing proper selection and optimal device placement. Moreover, ICE provides solid anatomical criteria to diagnose fenestrated atrial septal aneurysm, interatrial communications such as ostium primum and sinus venosus defects, partial anomalous pulmonary venous connection, and lipomatous hypertrophy of atrial septum.

Transcatheter closure of atrial septal defect and patent foramen ovale in adult patients using the Amplatzer occlusion device: no evidence for thrombus deposition with antiplatelet agents

Transcatheter closure of atrial septal defect (ASD) and patent foramen ovale (PFO) using the Amplatzer septal occluder (AGA Medical, Minneapolis, Minn) is an alternative to surgical closure. There are only limited data on the thrombogenic potential of the device. Thirty-seven patients (14 men, 23 women) underwent device closure of their ASD (n = 21) or PFO (n = 16) at a mean age of 47 +/- 14 years (range, 18-72). The device was successfully deployed in all patients. Thirty-three of 37 patients received antiplatelet therapy with clopidogrel bisulfate and aspirin for a total of 6 months. Four patients in atrial fibrillation were also anticoagulated (international normalized ratio 2.0 to 3.0). No thrombus was detected in any patient on either side of the device by transthoracic and transesophageal echocardiography and there were no cases of symptomatic thromboembolism. Right-to-left interatrial shunting was diagnosed by contrast transesophageal echocardiography with the Valsalva's maneuver. At 1-month follow-up, minimal right-to-left shunting was detected in 6 patients (2 PFO, 4 ASD). Two patients (PFO) had minimal shunting at 1 month but not at 6 months. In 3 patients (ASD), inducible right-to-left shunting persisted at 6 months. In conclusion, our results obtained from a modest number of patients indicate that antiplatelet therapy is safe and effective in preventing thrombus formation on the septal occluder surface.

Minimal access closure of patent foramen ovale: is it also recommended for patients with paradoxical emboli?

BACKGROUND

To investigate the outcome of the port-access approach for patent foramen ovale (PFO) closure and to identify the long-term risk of recurrent thromboembolic events in the paradoxical embolus subgroup after closure.

METHODS

Between 1997 and 2001, 31 patients underwent PFO closure using the port-access approach. Twelve of the 31 patients underwent PFO closure secondary to at least one paradoxical embolic event leading to either transient ischemic attack or cerebral infarction. All patients were followed longitudinally with office visits and telephone interviews.

RESULTS

The mean age was 47 years (range 18 to 85 years). All procedures were completed successfully without conversion to median sternotomy. The mean duration of aortic occlusion and cardiopulmonary bypass for all patients (n = 31) was 32 minutes (range 17 to 55 minutes) and 72 minutes (range 40 to 124 minutes), respectively. Postoperative complications included pneumonia/pulmonary embolus (n = 1), transient atrial fibrillation (n = 3, 9.7%), and exploration for bleeding (n = 3, 9.7%). No deaths were recorded. All patients were assessed using transesophageal echocardiography, and the closure of the PFO was documented. The average length of hospital stay was 3.8 days (range 2 to 10 days) for patients with paradoxical emboli. The mean follow-up period for the paradoxical embolus subgroup was 23 months (range 4 to 45 months). One patient was lost to follow-up. Neither transient ischemic attack nor cerebral infarction recurred during follow-up.

CONCLUSIONS

The port-access approach to PFO closure is a safe and effective procedure, with acceptable initial experience outcome and excellent low-risk rate of recurrent thromboembolic events.

Transcatheter closure of patent foramen ovale in patients with cerebral ischemia

OBJECTIVES

The present study was conducted to determine the safety of the transcatheter closure of a patent foramen ovale (PFO) in patients with cryptogenic cerebral ischemia and the midterm follow-up of recurrent thromboembolic events after interventional PFO closure.

BACKGROUND

Current therapeutic options for stroke prevention in patients with PFO and a history of thromboembolic events include chronic antithrombotics and more invasive treatments such as surgical closure or minor invasive transcatheter permanent closure of the PFO. Promising preliminary and pilot data with the Amplatzer Septal Occluder or the PFO-Star Occluder have been reported. Systematic and long-term data are still missing.

METHODS

A total of 276 consecutive patients with a PFO and a history of at least one thromboembolic event were recruited in four medical centers and underwent percutaneous PFO closure with the PFO-Star device. Follow-up data were analyzed over an average of 15.1 months, equivalent to 345 patient-years.

RESULTS

The implantation was successful in all 276 patients. Peri-interventional reversible complications included transient ST-segment elevations (1.8%) and transient ischemic attack (TIA) (0.8%). Two devices have been removed surgically. During follow-up the annual recurrence rate of thromboembolic events was 1.7% for TIA, 0% for stroke and 0% for peripheral emboli.

CONCLUSIONS

Interventional PFO closure with the PFO-Star device appears to be a reliable and promising technique resulting in a low recurrence rate of thromboembolic events, especially stroke in patients with a history of cryptogenic ischemia presumably due to paradoxical embolization. To our knowledge, this is the largest coherent and prospective study for interventional PFO closure.

Percutaneous closure with Amplatzer device is a safe and efficient alternative to surgery in adults with large atrial septal defects

BACKGROUND

In adults with atrial septal defect (ASD) and large right-to-left shunt, closure of the defect is recommended. Percutaneous closure is still rarely used in this population. This study presents the results of transcatheter closure with the Amplatzer occluder in such patients.

METHODS AND RESULTS

We studied 44 consecutive adult patients with a secundum ASD and 2 of the 3 following criteria: QP/QS >/=2 by oximetry, echocardiographic right ventricle overload, and ASD size >20 mm. Forty-two patients had a successful implantation. In 1 patient an unstable device was withdrawn; in another one, the device embolized in the pulmonary artery. At 6-month median follow-up, 95% had a complete closure; 2 patients with an additional defect had a small residual shunt. Major complications were the aforementioned embolization and a cerebrovascular accident in a patient with atrial fibrillation treated with aspirin. Others were minor and transitory: premature atrial beats in 3 patients, and paroxysmal atrial fibrillation and pulmonary edema in 1 patient each.

CONCLUSIONS

Transcatheter closure of large ASDs with the Amplatzer device is efficient with less morbidity than surgical closure.

Effect of nickel-titanium shape memory metal alloy on bone formation

The aim of this study was to determine the biocompatibility of NiTi alloy on bone formation in vivo. For this purpose we used ectopic bone formation assay which goes through all the events of bone formation and calcification. Comparisons were made between Nitinol (NiTi), stainless steel (Stst) and titanium-aluminium (6%)-vanadium (4%) alloy (Ti-6Al-4V), which were implanted for 8 weeks under the fascia of the latissimus dorsi muscle in 3-month-old rats. A light-microscopic examination showed no chronic inflammatory or other pathological findings in the induced ossicle or its capsule. New bone replaced part of the decalcified matrix with mineralized new cartilage and bone. The mineral density was measured with peripheral quantitative computed tomography (pQCT). The total bone mineral density (BMD) values were nearly equal between the control and the NiTi samples, the Stst samples and the Ti-6Al-4V samples had lower BMDs. Digital image analysis was used to measure the combined area of new fibrotic tissue and original implanted bone matrix powder around the implants. There were no significant differences between the implanted materials, although Ti-6Al-4V showed the largest matrix powder areas. The same method was used for measurements of proportional cartilage and new bone areas in the ossicles. NiTi showed the largest cartilage area (p < or = 0.05). Between implant groups the new bone area was largest in NiTi. We conclude that NiTi has good biocompatibility, as its effects on ectopic bone formation are similar to those of Stst, and that the ectopic bone formation assay developed here can be used for biocompatibility studies.