(Circulation. 2000;101:893.)
© 2000 American Heart Association, Inc.
Clinical Investigation and Reports |
Percutaneous Closure of Patent Foramen Ovale in Patients With Paradoxical Embolism
Long-Term Risk of Recurrent Thromboembolic Events
From the Swiss Cardiovascular Center Bern, University Hospital, Bern, Switzerland.
Correspondence to Bernhard Meier, MD, Professor of Cardiology, Swiss Cardiovascular Center Bern, University Hospital, 3010 Bern, Switzerland. E-mail bernhard.meier{at}insel.ch
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Background—Patients with a patent foramen ovale (PFO) and paradoxical embolism are at risk for recurrent thromboembolic events. This study investigated the long-term risk of recurrent thromboembolic events in patients with PFO and paradoxical embolism after percutaneous PFO closure.
Methods and Results—Since 1994, a total of 80 patients with PFO and at least 1 paradoxical embolic event (transient ischemic attack [TIA], cerebrovascular accident [CVA], peripheral embolism) have undergone percutaneous PFO closure with 5 different devices. There were 30 women and 50 men, with a mean age of 52±12 years. Sixty patients had only a PFO, whereas 20 patients had both a PFO and an atrial septal aneurysm. The implantation procedure was successful in 78 patients (98%). During 5 years of follow-up (mean, 1.6±1.4 years; range, 0.1 to 5.0 years), the actuarial annual risk to suffer a recurrent thromboembolic event was 2.5% for TIA, 0% for CVA, 0.9% for peripheral emboli, and 3.4% for the combined end point of TIA, CVA, or peripheral embolism. A postprocedural shunt was a predictor of recurrent paradoxical embolism (RR, 4.2; 95% CI, 1.1 to 17.8; P=0.03). The risk for recurrent thromboembolic events in patients with both atrial septal aneurysm and PFO was not significantly increased compared with patients with only PFO (RR, 1.0; 95% CI, 0.2 to 4.7; P=0.95).
Conclusions—Percutaneous PFO closure appears to be a promising technique in the prevention of recurrent systemic thromboembolism in patients with a PFO after a first event. Prospective studies comparing percutaneous PFO closure with antithrombotic medications or surgery must define its therapeutic value.
Key Words: foramen ovale • stroke • embolism
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
A patent foramen ovale (PFO) has been increasingly recognized as a mediator of paradoxical embolism,1 2 allowing passage of air, thrombus,3 4 and fat,5 with their subsequent systemic sequelae. Several case-control studies using contrast echocardiography established a strong association between cryptogenic stroke and the presence of PFO in young adults <55 years old.6 7 8 9 10 The relationship is less well defined in older age groups.8 9 11 Patients with PFO and paradoxical embolism are also at increased risk for recurrent thromboembolic events, with a combined cerebrovascular accident (CVA) and transient ischemic attack (TIA) rate of 3.4% to 3.8% per year.12 13 A large PFO size14 15 16 and presence of an atrial septal aneurysm (ASA)10 17 18 have been identified as morphological characteristics of PFO portending a high risk for paradoxical embolism.
The probability of PFO being the mediator of paradoxical embolism prompted the quest for a therapeutic and preventive strategy in affected patients. Surgical PFO closure has proved feasible, but the results have been mixed with respect to stroke prevention.19 20 Promising results of percutaneous PFO closure were initially reported by Bridges et al,21 who used the clamshell device in a sizeable cohort of patients with presumed paradoxical embolism. The present study prospectively assessed the long-term risk for recurrent thromboembolic events after percutaneous PFO closure with a variety of devices in 80 consecutive patients with paradoxical embolism during a follow-up period of up to 5 years.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Patient Population
Since April 1994, 80 patients with PFO and
1 documented
thromboembolic events have undergone percutaneous PFO
closure according to a study protocol approved by the local Ethics
Committee. A thromboembolic event was considered to be due to
paradoxical embolism when the following criteria were met: (1) presence
of PFO with or without ASA with spontaneous or provokable right-to-left
shunt during contrast transesophageal
echocardiography, (2) clinically and
neuroradiologically confirmed ischemic stroke or symptoms of
TIA with neuroradiologically identified intracranial ischemic
or clinically and radiologically verified extracranial
peripheral thromboembolism, and (3) exclusion of any
identifiable cause for the thromboembolic event other than the
PFO.22 All patients gave written informed consent to
participate in the study before the procedure.
Implantation Procedure
Venous access was gained via the right femoral vein, and the PFO
was passed under fluoroscopic guidance with a 6F multipurpose catheter.
With a standard 0.035-in exchange wire, the multipurpose catheter was
exchanged for a 6F to 14F transseptal sheath. The PFO occluder was
delivered through the transseptal sheath and placed within the PFO
under fluoroscopic guidance according to device-specific implantation
recommendations. Before the release of the PFO occluder, device
position was checked by right atrial contrast angiography to delineate
the atrial septum. Transesophageal
echocardiography was performed only during the
first 3 procedures. At the end of the procedure, the transseptal sheath
was removed, and hemostasis was achieved by manual compression. A
transthoracic contrast echocardiographic
examination was performed within 24 hours of
percutaneous PFO closure. All patients were treated
with aspirin 100 mg once daily for 3 to 6 months, at which time the
medication was stopped unless required for another indication.
Follow-Up Evaluation
At baseline before implantation and at 6 months after
percutaneous PFO closure, a
transesophageal contrast
echocardiographic study with aerated colloid solution
injected into the antecubital vein was performed.7 14 Any
recurrent thromboembolic events, including TIA, CVA, or
peripheral embolus, were considered primary end points of
the study. All patients were followed up prospectively for up to 5
years (range, 0.1 to 5 years). Patients with suspected thromboembolic
recurrence were reexamined by a neurologist, and whenever
possible, an imaging study, ie, MRI, CT, or angiography of the region
of interest, was repeated. As of the most recent contact, all patients
were subjected to a structured interview addressing recurrence
of thromboembolism, current health status, and quality of life. No
patient was lost to follow-up.
Definitions
ASA was diagnosed when the interatrial septum was abnormally
redundant, with an excursion of >10 mm into the right or left
atrium.17 TIA was defined as a temporary neurological
deficit lasting 
24 hours with complete resolution of symptoms. CVA
was defined as any new neurological deficit lasting >24 hours.
Peripheral embolism was defined as ischemia in any
end organ other than the brain caused by reduced blood flow in a
particular artery and objectively documented by Doppler flow, CT,
MRI, or angiographic imaging. Procedural complications were defined as
any adverse event that occurred within 24 hours of PFO occluder
implantation.
Statistical Analysis
Continuous variables were expressed as mean±SD.
Nominal variables were compared by 
2
analysis and paired continuous variables by a 2-sided,
paired t test. Statistical significance was assumed at a
value of P<0.05. Actuarial analysis of freedom from
recurrent thromboembolic events was calculated according to the
Kaplan-Meier method. Average annual event rates were calculated
according to the formula 1-[(1-P)1/n], where
P equals the cumulative event rate at n years of
follow-up.23 The log-rank test was used for
univariate analysis of independent variables
(age, sex, procedural complications, postprocedural shunt, or device
type) on the rate of recurrence. Estimates of the relative risk
(RR) and 95% CIs for each independent variable were obtained by
proportional hazards regression analysis.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Short-Term Results and Periprocedural Complications
Patient demographics are summarized in Table 1
. The implantation procedure was
successful in 78 patients (98%). There were 8 procedural complications
(10%), which are summarized in Table 2
and described below. In 1 patient, the procedure was aborted before
device delivery because of laceration of the femoral artery during
venous puncture with an ensuing retroperitoneal hematoma. This required
surgical revision, at which time the PFO was closed surgically. In
another patient with PFO and a large ASA, an Amplatzer occluder
embolized into the pulmonary artery 12 hours after the
procedure. The device was retracted percutaneously into
the femoral vein with an Amplatzer retrieval basket and from there
removed by local incision. Repeat PFO closure was not attempted. Thus,
in 2 patients, the implantation procedure failed.
|
|
One patient suffered an intraprocedural CVA, presumably due to air embolism through the transseptal sheath during device delivery. The clinical manifestations of aphasia and mild right hemiparesis completely resolved within 48 hours, at which time the patient was discharged home. When a reversed buttoned device was used, embolization of the counteroccluder into the pulmonary artery occurred in 2 patients. It was retrieved percutaneously. The occluding umbrella remained in the correct position, and therefore, placement of a second device was not necessary. Perforation of the right atrium with an 11F Mullins sheath resulted in a pericardial effusion with cardiac tamponade requiring needle pericardiocentesis in 1 patient who was orally anticoagulated. Embolization of air into the systemic circulation was responsible for transient inferior ST-segment elevations in 1 patient and visual disturbances in another patient during implantation of a PFO Star device.
A total of 5 different device types were implanted. There were no
obvious differences in the incidence of intraprocedural complications,
residual shunts, or recurrent thromboembolic events relative to the
implanted device (Table 3).
|
Recurrent Paradoxical Embolism
During a mean follow-up period of 1.6±1.4 years (range, 0.1 to 5
years), 8 recurrent thromboembolic events were encountered in 78
patients with an implanted device. These comprised 6 TIAs, no CVAs, and
2 peripheral emboli. One patient suffered a recurrent
peripheral embolus into the left leg requiring urgent
percutaneous embolectomy 1.6 years after
percutaneous PFO closure. At
transesophageal echocardiography, a
significant residual shunt was discovered, which was closed by
implantation of a second device. Another patient suffered a TIA and a
peripheral embolus simultaneously 0.6 years
after PFO closure, with occlusion of the left popliteal artery. No
residual shunt was found at transesophageal
echocardiography, but the patient subsequently
underwent surgical removal of the device with suture closure of the
PFO. This patient suffered another TIA 7 months after surgery. There
were no cardiac deaths, deaths due to device complications, or fatal
strokes during the observation period. The actuarial rates of
event-free survival for recurrent TIA, CVA, or the combined end point
of TIA, CVA, or peripheral embolism are displayed in Figure 1. The average annual recurrence
rates were 2.5% for TIA, 0% for CVA, 0.9% for peripheral
emboli, and 3.4% for the combined end point during the observation
period. The risk of recurrence was highest during the first
year after percutaneous PFO closure, with no further
events beyond 2 years after percutaneous PFO closure
(Table 4).
|
|
Prognostic Variables
An analysis of clinical predictors for recurrent
paradoxical embolism after percutaneous PFO closure is
summarized in Table 5. Sex or older age
(>55 years) did not influence the risk of recurrent thromboembolism.
The occurrence of intraprocedural complications had no measurable
influence on the risk of recurrence.
|
Patients were stratified according to atrial septal anatomy
into those with only PFO and those with both PFO and ASA (Figure 2, Table 5
). During 5 years of
follow-up, there was no statistically significant difference in the
annual risk of recurrent TIA (PFO only, 1.8%, versus PFO and ASA,
4.1%, P=0.7), recurrent CVA (PFO only, 0%, versus PFO and
ASA, 0%), recurrent peripheral emboli (PFO only,
1.3%, versus PFO and ASA 0%, P=0.4), and the combined end
point (PFO only, 3.1%, versus PFO and ASA, 4.1%, P=0.95)
between patients with only PFO and patients with both PFO and ASA.
|
indicates patients with only PFO; 
, patients with PFO and
ASA.
Complete PFO closure as assessed by color flow imaging and/or bubble
contrast injection under Valsalva maneuver was achieved in 57 patients
(73%), and a residual right-to-left shunt of some degree was
present in 21 patients (27%). The presence of a residual shunt
after percutaneous PFO closure as assessed by contrast
echocardiography was a predictor for recurrent
thromboembolic events with a relative risk of 4.2 (95% CI, 1.1 to
17.8; P=0.03). The average annual rates of
recurrence of the combined end point TIA, CVA, or
peripheral embolism were 6.8% in patients with versus
2.1% in patients without a postprocedural shunt (Figure 3).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Present Study
The present study, based on 128 patient-years, demonstrates that percutaneous PFO closure can be performed with a success rate of >95% and a periprocedural complication rate of 10% by use of a variety of PFO occluder devices. At up to 5 years of follow-up, the average annual rates of recurrent thromboembolic events were comparable to previously published data on medical12 13 24 and surgical19 20 25 26 treatment of PFO. The presence of a postprocedural shunt was a predictor of recurrent thromboembolic events. This not only emphasizes the importance of achieving complete PFO closure but also suggests that PFO is indeed the mediator of paradoxical embolism in this patient population.
The limitation of recurrent events to the first 2 years after
percutaneous PFO closure is of note. On one hand, the
recurrence rate appears to be rather high during the first year
after the procedure. This may be due to device-related problems, but it
also is in keeping with recent observations from other stroke series,
ie, the Oxfordshire Community Stroke Project23 and the
Northern Manhattan Stroke Study,27 in which the risk for
recurrence was highest during the first year after stroke. This
raises the question of whether a more intensive antithrombotic regimen
than 100 mg of aspirin should be recommended after
percutaneous PFO closure. A limitation in the
interpretation of the restriction of recurrence to the first 2
years after percutaneous PFO closure is that the mean
follow-up period of our study was 1.6±1.4 years (median, 1.4 years).
As detailed in Table 4, only 24 patients (31%) had a follow-up
period of 3 years, 14 patients (18%) of 4 years, and 7 patients (9%)
of 5 years. Therefore, recurrent events >2 years after device
implantation cannot be excluded with longer durations of follow-up in a
larger patient cohort.
The mean age of our patient population was 52±12 years, which is
10 years older than that of other series of PFO and paradoxical
embolism.12 13 The association of PFO with cryptogenic
stroke is less conclusively established in the elderly, with some
studies confirming the association between PFO and cryptogenic
stroke6 7 9 10 and others failing to show this
link.8 28 Although it appears that other causes of stroke
predominate in the elderly, the careful exclusion of known causes of
stroke should minimize the inclusion of nonqualifying elderly patients.
This is reflected in the observation of our study that older age (>55
years old) was not predictive of recurrent thromboembolism after
percutaneous PFO closure. Another finding of our study
is that the coexistence of an ASA with PFO did not result in a higher
recurrence rate of paradoxical embolism after
percutaneous PFO closure. This is in contrast to the
spontaneous course, in which the presence of an ASA in addition to PFO
signifies a high-risk population. Cabanes et al10 reported
that the relative risk of suffering a cryptogenic stroke was 4 times
higher in patients with PFO and 33 times higher in patients with both
PFO and ASA than in control subjects. The results of our study suggest
that the high-risk population of patients with both PFO and ASA might
derive a particularly high benefit from percutaneous
PFO closure. However, this conclusion is subject to inclusion of more
patients with a longer duration of follow-up.
Previous Studies of Percutaneous PFO
Closure
Bridges et al21 reported their experience of
percutaneous PFO closure with the clamshell device in
36 patients (mean age, 39 years). The implantation procedure was
successful in all patients, and complete closure as assessed by
echocardiography was achieved in 28 patients.
During follow-up (mean, 8 months; range, 1 to 24 months), there were no
recurrent CVAs or arterial embolisms, but 4 patients
experienced transient focal deficits. One patient was retrospectively
thought to be wrongly classified as having paradoxical embolism. The
mean time to recurrence was 5.5 months.
Ende et al29 summarized data on 10 patients (mean age, 40 years) undergoing percutaneous PFO closure with the buttoned device. Implantation was successful in 9 of 10 patients. Embolization of the counteroccluder into the left atrium was encountered in 1 patient, who subsequently underwent surgical closure. A residual shunt was noted in 4 patients at 1 month of follow-up, with subsequent closure by 6 to 12 months after the procedure. During a mean follow-up of 32 months in 9 patients, no recurrent neurological events were observed.
In a multicenter study30 using the atrial septal defect occlusion system (ASDOS) device for percutaneous PFO closure, only 1 of 46 patients (mean age, 44 years) with PFO and paradoxical embolism suffered a recurrent TIA 7 months after the procedure.
The early complication rate of the present study (8 patients, 10%) is high and asks for improvement. The underlying mechanisms for the complications encountered are (1) embolization of the device, (2) air embolism during device delivery, and (3) a learning curve in performing the procedure with different device designs. The buttoned device in particular poses a risk for embolization because of its potential for unbuttoning. Furthermore, anatomic variations such as a floppy atrial septum set the stage for device embolization. Air embolism during device delivery is a risk for intraprocedural stroke and myocardial infarction. It requires meticulous care for air evacuation at each step of the implantation procedure. Finally, as with any new technical method, there is a learning curve for each operator. However, the complication rate appears comparable to other studies. Specifically, Bridges et al,21 using the clamshell device, reported a reversible brachial plexus injury in 1 of 36 patients (2.8%); Ende et al29 described embolization of the counteroccluder of the buttoned device into the left atrium requiring percutaneous removal in 1 of 10 patients (10%); and Sievert et al,30 using the ASDOS device for both PFO and atrial septal defect closure, acknowledged embolization of the device in 2 patients (1%), pericardial effusion in 6 patients (3%), thrombus formation in 9 patients (6%), and infection in 2 patients (2%).
Other Treatment Modalities
Other treatment modalities for patients with PFO and presumed
paradoxical embolism include medical treatment with either
antiplatelet or antithrombin drugs and surgical PFO closure.
Comess et al24 described 33 patients with PFO and presumed paradoxical embolism who were followed up for 18 months and had a recurrent event rate of 16% per year (combined end point of TIA and CVA). In 132 patients <60 years old with PFO and cryptogenic stroke, Mas et al12 retrospectively analyzed the risk of recurrence during a mean follow-up period of 23 months during treatment with either aspirin (250 to 500 mg/d) or oral anticoagulation (target INR, 2 to 3). The average annual rate of recurrence was 1.2% for CVAs and 3.4% for the combined end point of TIA and CVA. Patients with both PFO and ASA had an average annual rate of recurrent stroke of 4.4%. Similar recurrence rates on medical treatment were reported from the Lausanne Stroke Registry.13 Ninety-two patients with PFO and cryptogenic stroke were treated with aspirin (250 to 500 mg/d), whereas 37 patients were treated with oral anticoagulation (target INR, 2.0 to 3.0). Eight patients were switched to aspirin after 3 months of oral anticoagulation. The average annual recurrence rate was 1.9% for CVA and 3.8% for the combined end point of TIA and CVA during a follow-up period of 3 years, with no statistically significant difference between the 2 antithrombotic drug regimens. A multicenter study in the United States funded by the NIH is currently investigating the effect of medical treatment on stroke recurrence in such patients by randomly assigning patients to either aspirin or anticoagulant therapy.
Surgical closure of PFO in patients with paradoxical embolism has been reported by Homma et al,20 who followed up 28 patients (mean age, 41 years) with PFO and cryptogenic stroke after surgical PFO closure by open thoracotomy. One recurrent ischemic stroke and 3 recurrent TIAs were observed, amounting to an actuarial recurrence rate of 20% at 13 months. This is in contrast to a series of 59 patients with a mean age of 42 years undergoing surgical closure by either open thoracotomy (n=44) or minimally invasive thoracotomy (n=15) reported by Ruchat et al.26 Except for 1 perioperative TIA, no further recurrent thromboembolic events were observed during a mean follow-up of 36 months.
Limitations
The following limitations apply to our study. (1) The
patient population is a selected cohort referred to our center for
percutaneous PFO closure and may differ from other
published series. (2) The diagnosis of paradoxical embolism rests on
presumptive assumptions. Most probably, PFO is not the sole mediator of
thromboembolic events in patients selected according to the criteria
used, and an alternative cause may become apparent only during
follow-up. (3) A weakness of this study is the use of 5 different
devices. Although our study did not find an obvious difference in
clinical outcome relative to the device type, this is probably due to
insufficient case numbers in each device group. There are important
differences between the devices used that may be clinically relevant.
For example, the incidence of postprocedural shunt, which correlates
with recurrence of thromboembolic events, was higher in
patients with the buttoned device. (4) The PFO comes in many, as yet
underestimated, anatomic phenotypes, ranging from small pinhole
openings over large tunnel-shaped structures to small atrial septal
defects with aneurysms and different degrees of redundant
interatrial tissue. This study does not address which device best fits
different anatomic subsets.
Conclusions
Percutaneous PFO closure appears to be a
promising new technique in the prevention of recurrent systemic
thromboembolism in patients with a PFO after a first event. Prospective
studies comparing percutaneous PFO closure with
antithrombotic medications or surgery must define its therapeutic
value.
Received June 24, 1999; revision received September 16, 1999; accepted October 1, 1999.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
-
Cohnheim J. Thrombose und Embolie: Vorlesung
über allgemeine Pathologie. Berlin, Germany:
Hirschwald; 1877:134.
-
Thompson T, Evans W. Paradoxical embolism.
Q J Med. 1930;23:135–150.
-
Falk V, Walther T, Krankenberg H, Mohr FW.
Trapped thrombus in a patent foramen ovale. Thorac Cardiovasc
Surg. 1997;45:90–92.[Medline]
[Order article via Infotrieve]
-
Caes FL, Van Belleghem YV, Missault LH, Coenye
KE, Van Nooten GJ. Surgical treatment of impending paradoxical
embolism through patent foramen ovale. Ann Thorac Surg. 1995;59:1559–1561.
[Abstract/Free Full Text]
-
Pell AC, Hughes D, Keating J, Christie J,
Busuttil A, Sutherland GR. Brief report: fulminating fat embolism
syndrome caused by paradoxical embolism through a patent foramen ovale.
N Engl J Med. 1993;329:926–929.
[Free Full Text]
-
Lechat P, Mas JL, Lascault G, Loron P, Theard M,
Klimczac M, Drobinski G, Thomas D, Grosgogeat Y. Prevalence of
patent foramen ovale in patients with stroke. N Engl J
Med. 1988;318:1148–1152.[Abstract]
-
Webster MW, Chancellor AM, Smith HJ, Swift DL,
Sharpe DN, Bass NM, Glasgow GL. Patent foramen ovale in young stroke
patients. Lancet. 1988;2:11–12.[Medline]
[Order article via Infotrieve]
-
Hausmann D, Mugge A, Becht I, Daniel WG.
Diagnosis of patent foramen ovale by transesophageal
echocardiography and association with cerebral and
peripheral embolic events. Am J Cardiol. 1992;70:668–672.[Medline]
[Order article via Infotrieve]
-
Di Tullio M, Sacco RL, Gopal A, Mohr JP, Homma
S. Patent foramen ovale as a risk factor for cryptogenic stroke.
Ann Intern Med. 1992;117:461–465.
-
Cabanes L, Mas JL, Cohen A, Amarenco P, Cabanes
PA, Oubary P, Chedru F, Guerin F, Bousser MG, de Recondo J. Atrial
septal aneurysm and patent foramen ovale as risk factors for
cryptogenic stroke in patients less than 55 years of age: a study using
transesophageal echocardiography.
Stroke. 1993;24:1865–1873.
[Abstract/Free Full Text]
-
de Belder MA, Tourikis L, Leech G, Camm AJ. Risk
of patent foramen ovale for thromboembolic events in all age groups.
Am J Cardiol. 1992;69:1316–1320.[Medline]
[Order article via Infotrieve]
-
Mas JL, Zuber M, French Study Group on Patent
Foramen Ovale and Atrial Septal Aneurysm. Recurrent
cerebrovascular events in patients with patent foramen ovale, atrial
septal aneurysm, or both and cryptogenic stroke or transient
ischemic attack. Am Heart J. 1995;130:1083–1088.[Medline]
[Order article via Infotrieve]
-
Bogousslavsky J, Garazi S, Jeanrenaud X,
Aebischer N, Van Melle G, Lausanne Stroke with Paradoxical Embolism
Study Group. Stroke recurrence in patients with patent foramen
ovale: the Lausanne Study. Neurology. 1996;46:1301–1305.
[Abstract/Free Full Text]
-
Homma S, Di Tullio MR, Sacco RL, Mihalatos D, Li
Mandri G, Mohr JP. Characteristics of patent foramen ovale associated
with cryptogenic stroke: a biplane transesophageal
echocardiographic study. Stroke. 1994;25:582–586.[Abstract]
-
Hausmann D, Mugge A, Daniel WG. Identification of
patent foramen ovale permitting paradoxic embolism. J Am
Coll Cardiol. 1995;26:1030–1038.[Abstract]
-
Stone DA, Godard J, Corretti MC, Kittner SJ,
Sample C, Price TR, Plotnick GD. Patent foramen ovale: association
between the degree of shunt by contrast transesophageal
echocardiography and the risk of future
ischemic neurologic events. Am Heart J. 1996;131:158–161.[Medline]
[Order article via Infotrieve]
-
Mugge A, Daniel WG, Angermann C, Spes C,
Khandheria BK, Kronzon I, Freedberg RS, Keren A, Denning K, Engberding
R, Sutherland GR, Vered Z, Erbel R, Visser CA, Lindert O, Hausmann D,
Wenzlaff P. Atrial septal aneurysm in adult patients: a
multicenter study using transthoracic and
transesophageal echocardiography.
Circulation. 1995;91:2785–2792.
[Abstract/Free Full Text]
-
Agmon Y, Khandheira BK, Meissner I, Gentile F,
Whisnant JP, Sicks JD, O’Fallon M, Covalt JL, Wiebers DO, Seward JB.
Frequency of atrial septal aneurysms in patients with cerebral
ischemic events. Circulation. 1999;99:1942–1944.
[Abstract/Free Full Text]
-
Devuyst G, Bogousslavsky J, Ruchat P, Jeanrenaud
X, Despland PA, Regli F, Aebischer N, Karpuz HM, Castillo V, Guffi M,
Sadeghi H. Prognosis after stroke followed by surgical closure of
patent foramen ovale: a prospective follow-up study with brain MRI and
simultaneous transesophageal and
transcranial Doppler ultrasound. Neurology. 1996;47:1162–1166.
[Abstract/Free Full Text]
-
Homma S, Di Tullio MR, Sacco RL, Sciacca RR,
Smith C, Mohr JP. Surgical closure of patent foramen ovale in
cryptogenic stroke patients. Stroke. 1997;28:2376–2381.
[Abstract/Free Full Text]
-
Bridges ND, Hellenbrand W, Latson L, Filiano J,
Newburger JW, Lock JE. Transcatheter closure of patent
foramen ovale after presumed paradoxical embolism.
Circulation. 1992;86:1902–1908.
[Abstract/Free Full Text]
-
Konstantinides S, Geibel A, Kasper W, Olschewski
M, Blumel L, Just H. Patent foramen ovale is an important predictor of
adverse outcome in patients with major pulmonary embolism.
Circulation. 1998;97:1946–1951.
[Abstract/Free Full Text]
-
Burn J, Dennis M, Bamford J, Sandercock P, Wade
D, Warlow C. Long-term risk of recurrent stroke after a first-ever
stroke: the Oxfordshire Community Stroke Project [published
erratum appears in Stroke 1994;25:1887]. Stroke. 1994;25:333–337.[Abstract]
-
Comess KA, De Rook FA, Beach KW, Lytle NJ, Golby
AJ, Albers GW. Transesophageal
echocardiography and carotid ultrasound in patients
with cerebral ischemia: prevalence of findings and recurrent
stroke risk. J Am Coll Cardiol. 1994;23:1598–1603.[Abstract]
-
Guffi M, Bogousslavsky J, Jeanrenaud X, Devuyst
G, Sadeghi H. Surgical prophylaxis of recurrent stroke in patients with
patent foramen ovale: a pilot study. J Thorac Cardiovasc
Surg. 1996;112:260–263.
[Abstract/Free Full Text]
-
Ruchat P, Bogousslavsky J, Hurni M, Fischer AP,
Jeanrenaud X, von Segesser LK. Systematic surgical closure of patent
foramen ovale in selected patients with cerebrovascular events due to
paradoxical embolism: early results of a preliminary study. Eur
J Cardiothorac Surg. 1997;11:824–827.[Abstract]
-
Sacco RL, Shi T, Zamanillo MC, Kargman DE.
Predictors of mortality and recurrence after hospitalized
cerebral infarction in an urban community: the Northern Manhattan
Stroke Study. Neurology. 1994;44:626–634.
[Abstract/Free Full Text]
-
Jones EF, Calafiore P, Donnan GA, Tonkin AM.
Evidence that patent foramen ovale is not a risk factor for cerebral
ischemia in the elderly. Am J Cardiol. 1994;74:596–599.[Medline]
[Order article via Infotrieve]
-
Ende DJ, Chopra PS, Rao PS.
Transcatheter closure of atrial septal defect or patent
foramen ovale with the buttoned device for prevention of
recurrence of paradoxic embolism. Am J Cardiol. 1996;78:233–236.[Medline]
[Order article via Infotrieve]
-
Sievert H, Babic UU, Hausdorf G, Schneider M,
Hopp HW, Pfeiffer D, Pfisterer M, Friedli B, Urban P.
Transcatheter closure of atrial septal defect and patent
foramen ovale with ASDOS device (a multi-institutional European trial).
Am J Cardiol. 1998;82:1405–1413.[Medline]
[Order article via Infotrieve]
This article has been cited by other articles:
 |
|
 |
|
  G. W. Albers, P. Amarenco, J. D. Easton, R. L. Sacco, and P. Teal Antithrombotic and Thrombolytic Therapy for Ischemic Stroke: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition) Chest, June 1, 2008; 133(6_suppl): 630S - 669S. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S D Treadwell, B Thanvi, and T G Robinson Stroke in pregnancy and the puerperium Postgrad. Med. J., May 1, 2008; 84(991): 238 - 245. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A Wahl, M Kunz, A Moschovitis, T Nageh, M Schwerzmann, C Seiler, H P Mattle, S Windecker, and B Meier Long-term results after fluoroscopy-guided closure of patent foramen ovale for secondary prevention of paradoxical embolism Heart, March 1, 2008; 94(3): 336 - 341. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Sievert, E. Fischer, C. Heinisch, N. Majunke, A. Roemer, and N. Wunderlich Transcatheter Closure of Patent Foramen Ovale Without an Implant: Initial Clinical Experience Circulation, October 9, 2007; 116(15): 1701 - 1706. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Gurtu, R. Grocott-Mason, M. Mason, C. Ilsley, and S. W. Dubrey Paradoxical coronary emboli following a long-haul airline flight Eur J Echocardiogr, October 1, 2007; 8(5): 390 - 392. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. R. Sukernik and E. Bennett-Guerrero The Incidental Finding of a Patent Foramen Ovale During Cardiac Surgery: Should It Always Be Repaired? A Core Review Anesth. Analg., September 1, 2007; 105(3): 602 - 610. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Hara, T. K. Jones, E. R. Ladich, R. Virmani, D. C. Auth, J. E. Eichinger, R. J. Sommer, R. A. Van Tassel, and R. S. Schwartz Patent Foramen Ovale Closure by Radiofrequency Thermal Coaptation: First Experience in the Porcine Model and Healing Mechanisms Over Time Circulation, August 7, 2007; 116(6): 648 - 653. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Krieg, H. Lapp, K. Pethig, J. F. Gummert, and T. Bossert Removal of a Left Atrial Thrombus Adherent to a Patent Foramen Ovale Occluder Ann. Thorac. Surg., April 1, 2007; 83(4): 1539 - 1541. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Bedard, J. Rodes-Cabau, C. Houde, A. Mackey, D. Rivest, S. Cloutier, M. Noel, A. Marrero, J.-M. Cote, P. Chetaille, et al. Enhanced Thrombogenesis but Not Platelet Activation Is Associated With Transcatheter Closure of Patent Foramen Ovale in Patients With Cryptogenic Stroke Stroke, January 1, 2007; 38(1): 100 - 104. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Spies, R. Strasheim, I. Timmermanns, and R. Schraeder Patent foramen ovale closure in patients with cryptogenic thrombo-embolic events using the Cardia PFO occluder Eur. Heart J., February 1, 2006; 27(3): 365 - 371. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D.R. Thomson Percutaneous PFO closure, further data but many unanswered questions Eur. Heart J., February 1, 2006; 27(3): 258 - 259. [Full Text] [PDF]
|
|
|
|
 |
|
 D. D. Hegland, G. A. Kunz, J. K. Harrison, and A. Wang Clinical problem-solving. A hole in the argument. N. Engl. J. Med., December 1, 2005; 353(22): 2385 - 2390. [Full Text] [PDF]
|
|
|
|
|
|
M. Schwerzmann and O. Salehian Hazards of percutaneous PFO closure Eur J Echocardiogr, December 1, 2005; 6(6): 393 - 395. [Full Text] [PDF]
|
|
|
|
 |
|
 H. Hara, R. Virmani, E. Ladich, S. Mackey-Bojack, J. Titus, M. Reisman, W. Gray, M. Nakamura, M. Mooney, A. Poulose, et al. Patent Foramen Ovale: Current Pathology, Pathophysiology, and Clinical Status J. Am. Coll. Cardiol., November 1, 2005; 46(9): 1768 - 1776. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Kumar, I. Khan, R. Milton, A. A. Ali, and D. J. O'Regan Pulmonary and Paradoxical Embolism in Protein C and S Deficient Patient Ann. Thorac. Surg., July 1, 2005; 80(1): 324 - 326. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. E. Sousa, M. A. Costa, E. M. Tuzcu, J. S. Yadav, and S. Ellis New Frontiers in Interventional Cardiology Circulation, February 8, 2005; 111(5): 671 - 681. [Full Text] [PDF]
|
|
|
|
|
|
A. Wahl, U. Krumsdorf, B. Meier, H. Sievert, S. Ostermayer, K. Billinger, M. Schwerzmann, U. Becker, C. Seiler, M. Arnold, et al. Transcatheter treatment of atrial septal aneurysm associated with patent foramen ovale for prevention of recurrent paradoxical embolism in high-risk patients J. Am. Coll. Cardiol., February 1, 2005; 45(3): 377 - 380. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. L. Geggel Conditions Leading to Pediatric Cardiology Consultation in a Tertiary Academic Hospital Pediatrics, October 1, 2004; 114(4): e409 - e417. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. W. Albers, P. Amarenco, J. D. Easton, R. L. Sacco, and P. Teal Antithrombotic and Thrombolytic Therapy for Ischemic Stroke: The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy Chest, September 1, 2004; 126(3_suppl): 483S - 512S. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G.P. Anzola, E. Morandi, F. Casilli, and E. Onorato Does Transcatheter Closure of Patent Foramen Ovale Really "Shut the Door?": A Prospective Study With Transcranial Doppler Stroke, September 1, 2004; 35(9): 2140 - 2144. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Windecker, A. Wahl, K. Nedeltchev, M. Arnold, M. Schwerzmann, C. Seiler, H. P. Mattle, and B. Meier Comparison of medical treatment with percutaneous closure of patent foramen ovale in patients with cryptogenic stroke J. Am. Coll. Cardiol., August 18, 2004; 44(4): 750 - 758. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. A. Wu, J. F. Malouf, J. A. Dearani, D. J. Hagler, G. S. Reeder, G. W. Petty, and B. K. Khandheria Patent Foramen Ovale in Cryptogenic Stroke: Current Understanding and Management Options Arch Intern Med, May 10, 2004; 164(9): 950 - 956. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. R. Messe, I. E. Silverman, J. R. Kizer, S. Homma, C. Zahn, G. Gronseth, and S. E. Kasner Practice Parameter: Recurrent stroke with patent foramen ovale and atrial septal aneurysm: Report of the Quality Standards Subcommittee of the American Academy of Neurology Neurology, April 13, 2004; 62(7): 1042 - 1050. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Devuyst, B. Piechowski-Jozwiak, T. Karapanayiotides, J.-W. Fitting, V. Kemeny, L. Hirt, L. A. Urbano, P. Arnold, G. van Melle, P.-A. Despland, et al. Controlled Contrast Transcranial Doppler and Arterial Blood Gas Analysis to Quantify Shunt Through Patent Foramen Ovale Stroke, April 1, 2004; 35(4): 859 - 863. |