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

Patent foramen ovale: The never-ending story

Several uncontrolled studies suggested a relationship between patent foramen ovale (PFO) and stroke. But recent data indicate that previous studies may overestimate the association between PFO and stroke. First, among patients who have had a cryptogenic stroke under treatment (with either warfarin or aspirin), the main data from the French PFO/atrial septal aneurysm (ASA) and PICSS (Patent Foramen Ovale in Cryptogenic Stroke Study), analyzed separately and in combination, indicate that PFO alone does not announce a significantly increased risk of recurrent stroke or death. But a small increase or decrease in risk cannot be excluded by this meta-analysis. Second, the data concerning the association between PFO and ASA are not clear and variable: the French PFO/ASA study found a significantly increased risk of recurrent stroke in patients with cryptogenic stroke and an association between PFO and ASA when treated medically. In contrast, PICSS found no association between the combined PFO-ASA with stroke or death, but the two populations had meaningful differences. Patients in the PICSS were much older than those in the French PFO/ASA study and had more risk factors for stroke, such as hypertension, diabetes, and history of prior stroke. Third, there were inadequate data to conclude about ASA alone. Possible practice recommendations could come from this meta-analysis: the evidence indicates that the risk of recurrent stroke or death is not different for patients with a PFO who underwent cryptogenic stroke compared to patients without a PFO who underwent a cryptogenic stroke under treatment with either aspirin or warfarin. But aspirin is more preferable (300 mg/d). However, it seems that the association between PFO and ASA confers an increased risk of recurrent stroke in medically treated patients who are less than 55 years of age. This subgroup of younger stroke patients may benefit from other treatments, such as the percutaneous closure of PFO or mini-invasive surgery to a lesser extent, but their efficacy and safety are not yet assessed by large randomized trials. However, we must also keep in mind that some stroke patients with PFO are psychologically attached to their PFO and prefer to close it.

Transseptal technique of percutaneous PFO closure results in persistent interatrial shunting

Our goal was to review the effectiveness of the transseptal and tunnel techniques of patent foramen ovale (PFO) closure. Percutaneous PFO closure is an increasingly common treatment for prevention of paradoxical embolism and is typically performed by passing the device through the defect tunnel itself. The transseptal technique, in which the septum primum is punctured to create a hole through which the device is passed, has been proposed for patients with long-tunnel PFO. From May 2001 to December 2003, 120 patients underwent PFO closure at our institution and were included in this analysis. Defect closure was assessed by transesophageal echocardiography (TEE) with bubble study. Clinical follow-up data were obtained by clinic visits or standardized telephone interviews. Device closure was successfully completed in all patients, with 12 (10%) undergoing transseptal closure and 108 (90%) undergoing tunnel closure. Immediately following the procedure, complete closure occurred in 6 of 12 (50%) of the transseptal group and 88 of 108 (81.5%) of the tunnel group (P = 0.0120). Of the 89 patients (74.2%) who returned for 6-month TEE, complete closure was demonstrated in 4 out of 10 (40%) of the transseptal group and 58 out of 79 (73.4%) of the tunnel group (P = 0.0303). There have been four transient ischemic attacks during a mean follow-up of 11 months. The transseptal technique of PFO closure results in a higher proportion of patients with persistent interatrial shunting when compared with the tunnel technique. Whether this is due to a difference in technique, device, or patient anatomy is unclear.

Percutaneous patent foramen ovale closure

This article discusses percutaneous patent foramen ovale closure.

Rare case of pulmonary arteriovenous fistula simulating residual defect after transcatheter closure of patent foramen ovale for recurrent paradoxical embolism

We report on a patient suffering from recurrent cerebrovascular events despite previous transcatheter closure of persistent foramen ovale (PFO) with a Helex occluder. There was evidence of persistent left-to-right atrial shunt shown by transesophageal contrast echocardiography and the patient was admitted to our institution for interventional closure of the supposed residual defect. However, the PFO was completely closed by the device and left pulmonary artery injections showed a pulmonary arteriovenous fistula in the left lower lobe. This rare malformation may well explain the recurrent paradoxical embolism. Transcatheter fistula closure with coils was performed successfully. This case underlines that the existence of an isolated pulmonary arteriovenous fistula as a right-to-left shunt in patients with cryptogenic stroke should not be overlooked, even if a PFO is present and pulmonary arteriovenous fistula is not suggested by the initial physical findings or chest X-ray.

Antithrombotic and Thrombolytic Therapy for Ischemic Stroke

This chapter about treatment and prevention of stroke is part of the 7th ACCP Conference on Antithrombotic and Thrombolytic Therapy: Evidence Based Guidelines. Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patients' values may lead to different choices (for a full understanding of the grading see Guyatt et al). Among the key recommendations in this chapter are the following: For patients with acute ischemic stroke (AIS), we recommend administration of i.v. tissue plasminogen activator (tPA), if treatment is initiated within 3 h of clearly defined symptom onset (Grade 1A). For patients with extensive and clearly identifiable hypodensity on CT, we recommend against thrombolytic therapy (Grade 1B). For unselected patients with AIS of > 3 h but < 6 h, we suggest clinicians not use i.v. tPA (Grade 2A). For patients with AIS, we recommend against streptokinase (Grade 1A) and suggest clinicians not use full-dose anticoagulation with i.v. or subcutaneous heparins or heparinoids (Grade 2B). For patients with AIS who are not receiving thrombolysis, we recommend early aspirin therapy, 160 to 325 mg qd (Grade 1A). For AIS patients with restricted mobility, we recommend prophylactic low-dose subcutaneous heparin or low molecular weight heparins or heparinoids (Grade 1A); and for patients who have contraindications to anticoagulants, we recommend use of intermittent pneumatic compression devices or elastic stockings (Grade 1C). In patients with acute intracerebral hematoma, we recommend the initial use of intermittent pneumatic compression (Grade 1C+). In patients with noncardioembolic stroke or transient ischemic attack (TIA) [ie, atherothrombotic, lacunar or cryptogenic], we recommend treatment with an antiplatelet agent (Grade 1A) including aspirin, 50 to 325 mg qd; the combination of aspirin and extended-release dipyridamole, 25 mg/200 mg bid; or clopidogrel, 75 mg qd. In these patients, we suggest use of the combination of aspirin and extended-release dipyridamole, 25/200 mg bid, over aspirin (Grade 2A) and clopidogrel over aspirin (Grade 2B). For patients who are allergic to aspirin, we recommend clopidogrel (Grade 1C+). In patients with atrial fibrillation and a recent stroke or TIA, we recommend long-term oral anticoagulation (target international normalized ratio, 2.5; range, 2.0 to 3.0) [Grade 1A]. In patients with venous sinus thrombosis, we recommend unfractionated heparin (Grade 1B) or low molecular weight heparin (Grade 1B) over no anticoagulant therapy during the acute phase.

Age Is Not a Predictor of Patent Foramen Ovale with Right-to-Left Shunt in Patients with Cerebral Ischemic Events

BACKGROUND

Patent foramen ovale (PFO) with or without atrial septal aneurysm (ASA) is highly associated with cerebral ischemic events in young patients. The prevalence of PFO and ASA in elderly patients with cerebral ischemic events is not well described.

OBJECTIVE

Our study is to evaluate the frequencies of PFO with right-to-left shunt (RLS) and ASA in elderly patients and to determine whether age is a predictor of flow-reversed PFO with RLS in cerebral ischemic events.

METHODS

A prospective registry for all consecutive patients with cerebral ischemic events who were evaluated by transesophageal echocardiography (TEE) for the detection of possible cardiac source of embolization was established and maintained in a university hospital. Patients' demographics including age, gender, ethnic origin, cerebrovascular risk factors, and all positive TEE data were collected from July 2000 to August 2001 for statistical analysis. A univariate and multivariate stepwise logistic regression analysis was performed.

RESULTS

In older patients the prevalence of PFO with RLS, PFO, and ASA was 25/118 (20%), 28/118 (24%), and 38/118 (32%), respectively, as opposed to younger patients, in whom it was 35/119 (30%), 39/119 (33%), and 38/119 (32%), respectively. Older patients had higher frequencies of hypertension (59; 69%), CAD (25; 21%), and prior history of stroke (23; 20%) as opposed to younger patients. Younger age (<60 years), gender, smoking history, hypertension, hyperlipidemia, CAD, and prior history of stroke were not associated with higher prevalence of PFO with RLS. Patent foramen ovale was associated with ASA (P < 0.001) and LVH (P < 0.019) in patients with TIA and stroke. In multivariate analysis only ASA (P < 0.001) remained significant with PFO, with RLS controlling for age, gender, and LVH.

CONCLUSIONS

PFO with RLS and ASA are frequently present in elderly stroke and/or TIA patients and age is not a predictor for PFO. Transesophageal echocardiography should be considered for all stroke and/or TIA patients irrespective of their age.

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

Transcatheter closure for atrial septal defect (ASD) and patent foramen ovale (PFO) is a promising alternative to surgical closure or anticoagulant therapy. A potential complication is thrombus formation on the device after implantation. From February 2001 to June 2003, 66 patients with atrial communication were treated successfully with the Amplatzer device (16 septal and 20 PFO occluders) or the CardioSEAL device (30). Patients were discharged on antiplatelet medication (aspirin and clopidogrel) and/or anticoagulation. Fifty patients (76%) had transesophageal echocardiography (TEE) 1 month after device implantation (28 +/- 10 days). No patient experienced a thromboembolic episode during follow-up. TEE revealed that thrombus formation occurred more frequently on the CardioSEAL device (5 of 23 patients; 22%) than on the Amplatzer device (0 of 27 patients; 0%) (p = 0.02). Although thrombus disappeared or markedly diminished after additional anticoagulation therapy in 3 patients, 1 patient had surgical explantation of the device due to progressive increase in the size of thrombus with hypermobility despite intensive anticoagulation therapy. There was no variable associated with the presence of thrombus formation on the occluder other than the use of the CardioSEAL device. One month after insertion, the CardioSEAL device is more likely to have thrombus present than the Amplatzer device.

Patent foramen ovale, systemic embolization and closure

The recognition, evaluation and treatment of patent foramen ovale has attracted increasing interest as the importance and frequency of paradoxical embolism has become better understood. The interest in this field has been driven largely by the widespread application of echocardiography with identification of a patent foramen ovale and/or an atrial septal aneurysm. The evaluation of the role of a patent foramen ovale in patients with a neurologic event is complex because the patent foramen ovale or atrial septal aneurysm may either be an innocent bystander or could be the etiologic mechanisms involved in the paradoxical embolus. In patients younger than 55 years, a causal relationship between a patent foramen ovale/atrial septal aneurysm and a neurologic ischemic event is considerably stronger than in those patients older than 55 years. In patients with a presumed diagnosis of paradoxical embolus in the setting of a patent foramen ovale, percutaneous closure is now possible and 2 devices are relatively widely used. Both of these devices reliably close the defect with a very acceptable risk profile and have been found in the longer term to be associated with excellent outcome. The exact role, however, that these devices play vis a vis continued medical therapy for prevention of recurrent events is being tested in 2 randomized clinical trials. The field continues to change with new technology being developed and with new applications. A recently exciting finding has been the identification that closure of a patent foramen ovale may be associated with dramatic improvement in symptoms of patients with disabling migraine headaches. Other potential applications of these devices include those patients who are deep-sea divers, in whom the potential for "bends" exists, or high altitude airplane pilots.

Transcatheter Amplatzer device closure of atrial septal defect and patent foramen ovale in patients with presumed paradoxical embolism

OBJECTIVE

To review our experience with, and profile the safety and efficacy of, the Amplatzer PFO (patent foramen ovale) occluder (APO) and Amplatzer septal occluder (ASO) used to close PFO and/or atrial septal defect (ASD) in patients with paradoxical embolism (PE).

PATIENTS AND METHODS

Between April 1998 and November 2002, 103 patients at the Mayo Clinic in Rochester, Minn, and Scottsdale, Ariz, mean age 52.4 years, with presumed PE (transient ischemic attack [n=22], stroke [n=77], or peripheral emboli [n=4]) underwent transcatheter device closure of PFO (n=81), ASD (n=12), and ASD/PFO (n=10) with 106 devices (APO [n=22] or ASO [n=84]).

RESULTS

All devices deployed successfully, and no patients died. Procedural complications included atrial fibrillation (n=2), vessel injury (n=3), profound sinus node dysfunction (n=1), and device embolization with successful retrieval (n=1). At 3 months, 7 of 95 monitored patients had trivial residual shunt; at 12 months, 2 of 28 monitored patients had trivial residual shunt. Three patients had recurrent events--2 transient ischemic attacks and 1 retinal artery occlusion--at a mean +/- SD follow-up of 8.3 +/- 8.1 months (range, 1-34 months). None of these 3 patients had residual shunt or evidence of intracardiac thrombus. The average annual recurrence of all events was 3.6% at 23 months. The overall mean +/- SD freedom from recurrence of all events was 98.9% +/- 1.2% and 83.8% +/- 10.2% at 12 and 29 months of follow-up, respectively.

CONCLUSIONS

Transcatheter device closure of PFO and/or ASD with use of APO/ASO in patients with presumed PE is effective and safe. Recurrent events may occur in the absence of a residual shunt.

Clinical outcomes of patent foramen ovale closure for paradoxical emboli without echocardiographic guidance

The objective of this study was to determine the feasibility of device closure of patent foramen ovale (PFO) for presumed paradoxical emboli without echocardiographic guidance or balloon sizing and the clinical outcome after device closure. Closure of the PFO has been proposed as an alternative to anticoagulation in patients with presumed paradoxical emboli. At present, most centers perform device closure with transesophageal echocardiographic guidance and balloon sizing of the defect. Between May 1998 and April 2002, 92 consecutive patients underwent device closure for a PFO using fluoroscopic monitoring only. Procedural success and major complications were recorded. Follow-up outcomes were recurrence rate and residual atrial shunting on transthoracic echocardiography. All patients (mean age, 45 +/- 13 years; 52% male) had successful device deployment using either the CardioSeal (n = 78) and Amplatzer (n = 14) PFO occluders with no major complications. Mean procedure time and fluoroscopy time was 27 +/- 13 and 6 +/- 4 min, respectively. One patient had a residual shunt on echocardiography at 1 year. Cumulative event-free survival for recurrence of paradoxical embolus at 1 year was 97.3% +/- 1.8%. This study provides a basis for device closure of PFO becoming a safe, day-case procedure, resulting in a low rate of residual shunting and recurrent thromboembolic events.

Transcatheter closure of atrial septal defects in children with a hypoplastic right ventricle

The efficacy and safety of device closure of atrial defects in children with complex congenital heart disease and a hypoplastic right ventricle have not been detailed. The objective of this study was to determine the clinical impact and outcomes of a staged surgical catheter-based management strategy. A retrospective analysis of 17 children with a hypoplastic right ventricle who had undergone cardiac catheterization and attempted device occlusion of an atrial defect was undertaken. Clinical data, anatomical diagnoses, previous surgeries, and interventions were noted. The clinical course and echocardiographic findings were compared before and after defect closure (6 +/- 4 months of follow-up). Nine children had pulmonary atresia with an intact ventricular septum, six had Ebstein's anomaly of the tricuspid valve, and two had isolated right ventricular hypoplasia. The mean age at defect closure was 6.6 +/- 3.4 years. Under general anesthesia, closure of the atrial defect was undertaken after initial temporary test occlusion. The Qp:Qs ratio before closure was 1.1 +/- 0.4. Oxygen saturation improved in all children from 91% +/- 1% to 98% +/- 1% (P < 0.0005). Mean right atrial pressure increased from 9 +/- 3 to 11 +/- 4 mm Hg after closure, but the difference was not statistically significant (P = 0.2). Follow-up revealed an increased right ventricular length (P = 0.009) and Z-score (P = 0.02), although no significant increase in the diameter of the tricuspid valve annulus was observed in children with pulmonary atresia. Right ventricular systolic pressures or systolic function did not change significantly during follow-up (P = 0.5 and 0.29, respectively). Exercise tolerance improved in all children and clinical evidence of right ventricular decompensation was absent. Catheter closure of atrial defects in children with a hypoplastic right ventricle is well tolerated, safe, and effective as a treatment strategy in the staged management.

Indication and Techniques of Transcatheter Closure of Patent Foramen Ovale

A potential causal relationship of a patent foramen ovale (PFO) and a stroke was first suggested by Cohnheim in 1877.1 Today, this correlation is generally accepted. However, there is still no "gold standard" for the treatment of patients with presumed paradoxical embolism. This article reviews the epidemiology of and the diagnostic methods for PFO, the clinical relationship between PFO and cerebral ischemia, as well as indications and techniques for transcatheter closure of PFO. In the author's opinion, transcatheter PFO closure represents an elegant management for selected patients at risk.

Transcatheter closure of patent foramen ovale associated with paradoxical embolism using the amplatzer PFO occluder: Initial and intermediate-term results of the U.S. multicenter clinical trial

Closure of patent foramen ovale (PFO) has been proposed as an alternative to anticoagulation in patients with presumed paradoxical emboli. We report the immediate and mid-term results of the phase 1 U.S. Multicenter Clinical Trial of patients who underwent transcatheter PFO closure for paradoxical embolism using the new Amplatzer PFO device. Fifty patients (28 male/22 female) underwent catheter closure of their PFOs at a mean age of 41 +/- 11 years. Thirty-six patients had ischemic stroke, 10 had transient ischemic attack, and 4 had peripheral embolism. Seventeen patients had atrial septal aneurysm. The implantation procedure was successful in 49/49 patients; one patient did not have a PFO. Complete closure was seen immediately after the procedure in 26/49 patients; 17 had minimal residual shunt, 4 had moderate and 2 had large residual shunts. The median fluoroscopy time was 10.5 min (2.8-43 min). There were no complications related to the device. One patient developed an arteriovenous fistula at the catheter site requiring surgical repair. At a mean follow-up interval of 16.5 +/- 7.2 months, there were no deaths or recurrent neurological or peripheral embolic events. Eight patients reported an episode of dizziness or palpitations (four of them within 18 days of the procedure). No episodes of atrial dysrhythmias were noted. Contrast bubble study at last follow-up documented complete closure in 45/48 patients; one patient had minimal, one had moderate residual shunt, and one had a large shunt. One patient was lost to follow-up. We conclude that catheter closure of PFO associated with stroke/transient ischemic attack or peripheral embolism using the new Amplatzer PFO device is a safe and effective method in preventing recurrence of such episodes. Randomized clinical trials comparing device closure versus continued medical therapy are underway.

Preliminary experience with a new 18 mm Amplatzer PFO occluder for small persistent foramen ovale

We report our initial experience with a new 18 mm Amplatzer PFO device for the closure of small PFO. Patients were selected by a semiquantitative sizing procedure using the circle of a diagnostic pigtail catheter instead of a sizing balloon. In all eight patients, the device was easy to implant without problems. Due to its size, it has the potential to minimize the risk of inadvertent atrial erosion or perforation after deployment and thus will enhance the safety of interventional PFO closure.

Secondary embolization of a Helex occluder implanted into a secundum atrial septal defect

We report on a 2-year-old patient with atrial septal defect with a stretched diameter of 11 mm. The defect was closed uneventfully by use of a 25 mm Helex device. There was only trivial residual shunting (1 mm at the cranial margin of the device). After 36 hr, routine postinterventional echocardiography confirmed device embolization into the pulmonary artery. The child was asymptomatic. Transcatheter device retrieval with snares of different sizes, bioptomes, and retrieval forceps failed due to the mismatch of the diameter of the device and the small diameter of the pulmonary artery. Therefore, the device was retrieved surgically and the ASD closed by primary sutures. Secondary embolization of a Helex device complicated the closure of an uncomplicated atrial septal defect with a device-to-defect ratio according to the manufacturer's suggestion due to a mechanism not yet understood.

Intracardiac echocardiography is superior to conventional monitoring for guiding device closure of interatrial communications

BACKGROUND

This study sought to test whether intracardiac echocardiography (ICE) is superior to conventional monitoring in guiding device closure of interatrial communications (atrial septal defect [ASD] and patent foramen ovale [PFO]).

METHODS AND RESULTS

Forty-four patients undergoing device closure of ASD (n=6) or PFO (n=38) were randomized to have the procedure guided by either ICE (group 1; n=22) or by transesophageal echocardiography (TEE) (group 2; n=22). All interventions were completed successfully. In 1 patient from group 2, atrial fibrillation occurred 1 day after device implantation; the patient was successfully cardioverted on the next day. There were no other complications. Fluoroscopy time (FT) (6.0+/-1.7 minutes versus 9.5+/-1.6 minutes; P<0.0001) as well as procedure time (PT) (33.4+/-4.7 minutes versus 37.8+/-5.6 minutes; P<0.01) were shorter in group 1 than in group 2. Group 2 patients required general anesthesia without (n=19) or with endotracheal intubation (n=3). In contrast, ICE allowed continuous monitoring of the whole procedure, including balloon sizing before device closure, without sedation.

CONCLUSIONS

ICE is a safe tool to guide device closure of PFO and ASD. Supine patients tolerate ICE better than TEE. ICE reduces FT and PT. ICE seems to be advantageous, especially when long continuous or repeated echocardiographic viewing is required.