Outcome of patients with cryptogenic stroke and patent foramen ovale

Heart Brain Clinic: An Integrated Approach to Stroke Care

Background and Objectives

Multidisciplinary clinics have been shown to improve care. Patients with patent foramen ovale (PFO)-associated stroke need evaluation by cardiology and neurology specialists. We report our experience creating a multidisciplinary Structural Heart Brain Clinic (HBC) with a focus on patients with PFO-associated stroke.

Methods

Demographic and clinical data were retrospectively collected for patients with PFO-associated ischemic stroke. Patients with PFO-associated stroke were divided into a standard care group and Heart Brain Clinic group for analysis. Outcome measures included time from stroke to PFO closure and number of clinic visits before decision regarding closure. Nonparametric analysis evaluated differences in median time to visit and clinical decision, while the chi square analysis compared differences in categorical variables between groups.

Results

From February 2017 to December 2021, 120 patients were evaluated for PFO-associated stroke. The Structural HBC began in 12/2018 with coordination between Departments of Neurology and Cardiology. For this analysis, 41 patients were considered in the standard care group and 79 patients in the HBC group. During data analysis, 107 patients had received recommendations about PFO closure. HBC patients required fewer clinic visits (p = 0.001) before decision about closure; however, among patients who underwent PFO closure, there was no significant difference in weeks from stroke to PFO closure. Clinicians were more likely to recommend against PFO closure among patients seen in HBC compared with those seen in standard care (p = 0.021).

Discussion

Our data demonstrate that a multidisciplinary, patient-centered approach to management of patients with PFO-associated ischemic stroke is feasible and may improve the quality of care in this younger patient population. The difference in recommendation to not pursue PFO closure between groups may reflect selection and referral bias. Additional work is needed to determine whether this approach improves other aspects of care and outcomes.

Risk of Perioperative Stroke in Patients with Patent Foramen Ovale: A Systematic Review and Meta-Analysis

BACKGROUND

Patent foramen ovale (PFO) is a common congenital cardiac abnormality. Risk of stroke increases perioperatively; however, the association of PFO with perioperative stroke risk remains unclear. We conducted a systematic review to inform the risk of perioperative stroke in patients with PFO undergoing surgery.

METHODS

EMBASE, MEDLINE, and Cochrane databases were searched from inception to January 2020. We described methods used for establishing PFO and perioperative stroke diagnosis. We conducted meta-analyses to obtain pooled estimates for risk of stroke in patients with and without PFO in different surgical populations.

RESULTS

Ten articles with a total of 20,858,011 patients met the eligibility criteria. Prevalence of PFO ranged from 0.06-1.4% based on ICD code diagnosis and 10.4-40.4% based on echocardiography diagnosis. Perioperative stroke was observed in 0-25% of patients with PFO, and 0-16.7% without PFO. Studies that use echocardiography to diagnose PFO found no association between PFO and perioperative stroke. Studies that used ICD codes, found strong association but were highly heterogenous. PFO was not associated with a risk of perioperative stroke in cardiac and transplant surgeries. While the adjusted odds ratios for stroke were substantial for orthopedic, general, genitourinary, neuro, and thoracic surgeries (with PFO status established based on ICD codes), data heterogeneity and quality of data create significant uncertainty.

CONCLUSION

In conclusion, PFO is likely a risk factor for perioperative stroke in select types of surgeries. However, this is based on a very low-quality evidence. Rigorous, prospective studies are needed to further investigate this relationship.

Comparison of antithrombotic strategies in patients with cryptogenic stroke and patent foramen ovale: an updated meta-analysis

PURPOSE

Patients with patent foramen ovale (PFO) and cryptogenic ischemic stroke (CS) are at risk for stroke recurrence. The optimal antithrombotic strategy in patients who undergo medical management is still debated.

METHODS

We systematically searched the literature for studies that reported on cerebrovascular event recurrences and/or death in patients with PFO treated with oral anticoagulation (OAC) or antiplatelet therapy (APT) for secondary prevention of CS. The efficacy endpoints were stroke recurrence and the composite of stroke, transient ischemic attack or all-cause death. Major bleedings represented the safety endpoint.

RESULTS

A total of 16 studies with 3953 patients (OAC = 1527, APT = 2426) were included. Weighted mean follow-up was 2.9 years. OAC was associated with a significant reduction in the risk of stroke compared with APT (RR 0.65; 95% CI 0.44-0.95; ARR 2%, NNT 49), while no difference was found regarding the composite outcome (RR 0.78; 95% CI 0.57-1.07) and the safety outcome (RR 1.57; 95% CI 0.85-2.90; p = 0.15).

CONCLUSIONS

OAC was more effective than APT in reducing the risk of stroke recurrence in patients with PFO and CS, without a significant increase in the risk of major bleedings. Our findings support the need for further randomized data focused on the comparison of antithrombotic strategies in this setting.

Prior Stroke in PFO Patients Is Associated With Both PFO-Related and -Unrelated Factors

Background and Purpose: To identify factors associated with prior stroke at presentation in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO).

Methods: We studied cross-sectional data from the International PFO Consortium Study (NCT00859885). Patients with first-ever stroke and those with prior stroke at baseline were analyzed for an association with PFO-related (right-to-left shunt at rest, atrial septal aneurysm, deep venous thrombosis, pulmonary embolism, and Valsalva maneuver) and PFO-unrelated factors (age, gender, BMI, hypertension, diabetes mellitus, hypercholesterolemia, smoking, migraine, coronary artery disease, aortic plaque). A multivariable analysis was used to adjust effect estimation for confounding, e.g., owing to the age-dependent definition of study groups in this cross-sectional study design.

Results: We identified 635 patients with first-ever and 53 patients with prior stroke. Age, BMI, hypertension, diabetes mellitus, hypercholesterolemia, coronary artery disease, and right-to-left shunt (RLS) at rest were significantly associated with prior stroke. Using a pre-specified multivariable logistic regression model, age (Odds Ratio 1.06), BMI (OR 1.06), hypercholesterolemia (OR 1.90) and RLS at rest (OR 1.88) were strongly associated with prior stroke.Based on these factors, we developed a nomogram to illustrate the strength of the relation of individual factors to prior stroke.

Conclusion: In patients with CS and PFO, the likelihood of prior stroke is associated with both, PFO-related and PFO-unrelated factors.

Anticoagulant vs. antiplatelet therapy in patients with cryptogenic stroke and patent foramen ovale: an individual participant data meta-analysis

AIMS

The preferred antithrombotic strategy for secondary prevention in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO) is unknown. We pooled multiple observational studies and used propensity score-based methods to estimate the comparative effectiveness of oral anticoagulation (OAC) compared with antiplatelet therapy (APT).

METHODS AND RESULTS

Individual participant data from 12 databases of medically treated patients with CS and PFO were analysed with Cox regression models, to estimate database-specific hazard ratios (HRs) comparing OAC with APT, for both the primary composite outcome [recurrent stroke, transient ischaemic attack (TIA), or death] and stroke alone. Propensity scores were applied via inverse probability of treatment weighting to control for confounding. We synthesized database-specific HRs using random-effects meta-analysis models. This analysis included 2385 (OAC = 804 and APT = 1581) patients with 227 composite endpoints (stroke/TIA/death). The difference between OAC and APT was not statistically significant for the primary composite outcome [adjusted HR = 0.76, 95% confidence interval (CI) 0.52-1.12] or for the secondary outcome of stroke alone (adjusted HR = 0.75, 95% CI 0.44-1.27). Results were consistent in analyses applying alternative weighting schemes, with the exception that OAC had a statistically significant beneficial effect on the composite outcome in analyses standardized to the patient population who actually received APT (adjusted HR = 0.64, 95% CI 0.42-0.99). Subgroup analyses did not detect statistically significant heterogeneity of treatment effects across clinically important patient groups.

CONCLUSION

We did not find a statistically significant difference comparing OAC with APT; our results justify randomized trials comparing different antithrombotic approaches in these patients.

PFO Closure for Cryptogenic Stroke

A patent foramen ovale (PFO) is a common finding in the general population and has been theorized to be a mechanism for ischemic stroke primarily due to a deep venous thrombus embolizing through the shunt into the arterial circulation. There has been much debate regarding the association between PFO and stroke, especially in the case of a cryptogenic stroke (i.e., stroke of unknown etiology) in a younger patient without other risk factors. Traditionally, when a PFO is detected, antithrombotic therapy to mitigate risk of a future ischemic event has been the mainstay of treatment. More recently, both surgical and transcatheter closure of a PFO have been widely utilized. However, there are only few randomized controlled trials assessing the efficacy of PFO closure for stroke prevention.

Recurrent Stroke/TIA in Cryptogenic Stroke Patients with Patent Foramen Ovale

Background:

Patent foramen ovale (PFO) is present in 40% of patients with cryptogenic stroke and may be associated with paradoxical emboli to the brain. Therapeutic options include antiplatelet agents, anticoagulation, percutaneous device and surgical closure. We assessed the hypothesis that there are differences in rates of recurrent TIA or stroke between patients in the four treatment groups.

Methods:

Patients presenting from January 1997 with cryptogenic stroke or TIA and PFO were followed prospectively until June 2003. Treatment choice was made on an individual case basis. The primary outcome was recurrent stroke. The secondary outcome was a composite of stroke, TIA, and vascular death.

Results:

Baseline. Our cohort consisted of 121 patients; 64 (53%) were men. Median age was 43 years. Sixty-nine percent presented with stroke and 31% with TIA. One or more vascular risk factor was present in 40%. Atrial septal aneurysm (ASA) was present in 24%. Treatment consisted of antiplatelet agents (34%), anticoagulation (17%), device (39%) and surgical closure (11%). Follow-up. Recurrent events occurred in 16 patients (9 antiplatelet, 3 anticoagulation, 4 device closure); 7 were strokes, 9 were TIA. Comparing individual treatments there was a trend toward more strokes in the antiplatelet arm (p=0.072); a significant difference was seen for the composite endpoint (p=0.012). Comparing closure versus combined medical therapy groups, a significant difference was seen for primary (p=0.014) and secondary (p=0.008) outcomes, favoring closure. Age and pre-study event predicted outcome.

Conclusion:

Patent foramen ovale closure was associated with fewer recurrent events. Complications of surgical and device closure were self-limited.

Stroke Recurrence and its Prevention in Patients with Patent Foramen Ovale

BACKGROUND

It is unclear whether medical or invasive (surgical or catheter interventional) treatment is preferable to prevent recurrence of cerebral ischemia in patients with patent foramen ovale (PFO) as the suspected cause of stroke and what the role of concomitant risk factors is in stroke recurrence.

METHODS

Over a period of ten years, 124 patients (mean age 51 +/- 15 years) with cryptogenic cerebral ischemia and PFO were included into the study and prospectively followed over a mean of 52 +/- 32 months. Of these, 83 were treated medically, 34 underwent transcatheter closure, and seven had surgical closure of the foramen. Of the medically treated patients, 11 stopped medication during follow-up. Recurrent ischemic events and risk factors for recurrence were analyzed.

RESULTS

Annual stroke recurrence rates were generally low and comparable in catheter and medically treated patients, and in patients who had stopped medication (2.9%/2.1%2.2%/year). Patients suffering from recurrence after transcatheter closure (n = 2) both had residual shunts. No stroke recurrence was observed in the few surgically treated patients. An atrial septal aneurysm was not a predictor of recurrent or multiple strokes (p > 0.05, OR = 0.31, and OR = 0.74). Large shunts and a history of previous ischemic events were considerably more frequent in patients with recurrent strokes (p < 0.05, OR = 5.0, and OR = 4.4). Pulmonary embolism and case fatality rates were significantly higher in patients with stroke recurrence (p < 0.001, and p < 0.01).

CONCLUSIONS

The absolute risk of recurrent cerebrovascular events in patients with PFO receiving medical or catheter interventional therapy is low. The small group of untreated patients had a comparably low rate of stroke recurrences. Previous ischemic events and shunt size were risk factors in this observational study. Given conflicting findings across multiple studies, enrollment into a randomized controlled trial would be the optimal choice.

Transesophageal echocardiography in cryptogenic stroke and patent foramen ovale: analysis of putative high-risk features from the risk of paradoxical embolism database

BACKGROUND

Patent foramen ovale (PFO) is associated with cryptogenic stroke (CS), although the pathogenicity of a discovered PFO in the setting of CS is typically unclear. Transesophageal echocardiography features such as PFO size, associated hypermobile septum, and presence of a right-to-left shunt at rest have all been proposed as markers of risk. The association of these transesophageal echocardiography features with other markers of pathogenicity has not been examined.

METHODS AND RESULTS

We used a recently derived score based on clinical and neuroimaging features to stratify patients with PFO and CS by the probability that their stroke is PFO-attributable. We examined whether high-risk transesophageal echocardiography features are seen more frequently in patients more likely to have had a PFO-attributable stroke (n=637) compared with those less likely to have a PFO-attributable stroke (n=657). Large physiologic shunt size was not more frequently seen among those with probable PFO-attributable strokes (odds ratio [OR], 0.92; P=0.53). The presence of neither a hypermobile septum nor a right-to-left shunt at rest was detected more often in those with a probable PFO-attributable stroke (OR, 0.80; P=0.45; OR, 1.15; P=0.11, respectively).

CONCLUSIONS

We found no evidence that the proposed transesophageal echocardiography risk markers of large PFO size, hypermobile septum, and presence of right-to-left shunt at rest are associated with clinical features suggesting that a CS is PFO-attributable. Additional tools to describe PFOs may be useful in helping to determine whether an observed PFO is incidental or pathogenically related to CS.

An index to identify stroke-related vs incidental patent foramen ovale in cryptogenic stroke

OBJECTIVE

We aimed to create an index to stratify cryptogenic stroke (CS) patients with patent foramen ovale (PFO) by their likelihood that the stroke was related to their PFO.

METHODS

Using data from 12 component studies, we used generalized linear mixed models to predict the presence of PFO among patients with CS, and derive a simple index to stratify patients with CS. We estimated the stratum-specific PFO-attributable fraction and stratum-specific stroke/TIA recurrence rates.

RESULTS

Variables associated with a PFO in CS patients included younger age, the presence of a cortical stroke on neuroimaging, and the absence of these factors: diabetes, hypertension, smoking, and prior stroke or TIA. The 10-point Risk of Paradoxical Embolism score is calculated from these variables so that the youngest patients with superficial strokes and without vascular risk factors have the highest score. PFO prevalence increased from 23% (95% confidence interval [CI]: 19%-26%) in those with 0 to 3 points to 73% (95% CI: 66%-79%) in those with 9 or 10 points, corresponding to attributable fraction estimates of approximately 0% to 90%. Kaplan-Meier estimated stroke/TIA 2-year recurrence rates decreased from 20% (95% CI: 12%-28%) in the lowest Risk of Paradoxical Embolism score stratum to 2% (95% CI: 0%-4%) in the highest.

CONCLUSION

Clinical characteristics identify CS patients who vary markedly in PFO prevalence, reflecting clinically important variation in the probability that a discovered PFO is likely to be stroke-related vs incidental. Patients in strata more likely to have stroke-related PFOs have lower recurrence risk.

The risk of paradoxical embolism (RoPE) study: initial description of the completed database

BACKGROUND

Detecting a benefit from closure of patent foramen ovale in patients with cryptogenic stroke is hampered by low rates of stroke recurrence and uncertainty about the causal role of patent foramen ovale in the index event. A method to predict patent foramen ovale-attributable recurrence risk is needed. However, individual databases generally have too few stroke recurrences to support risk modeling. Prior studies of this population have been limited by low statistical power for examining factors related to recurrence.

AIMS

The aim of this study was to develop a database to support modeling of patent foramen ovale-attributable recurrence risk by combining extant data sets.

METHODS

We identified investigators with extant databases including subjects with cryptogenic stroke investigated for patent foramen ovale, determined the availability and characteristics of data in each database, collaboratively specified the variables to be included in the Risk of Paradoxical Embolism database, harmonized the variables across databases, and collected new primary data when necessary and feasible.

RESULTS

The Risk of Paradoxical Embolism database has individual clinical, radiologic, and echocardiographic data from 12 component databases, including subjects with cryptogenic stroke both with (n = 1925) and without (n = 1749) patent foramen ovale. In the patent foramen ovale subjects, a total of 381 outcomes (stroke, transient ischemic attack, death) occurred (median follow-up 2·2 years). While there were substantial variations in data collection between studies, there was sufficient overlap to define a common set of variables suitable for risk modeling.

CONCLUSION

While individual studies are inadequate for modeling patent foramen ovale-attributable recurrence risk, collaboration between investigators has yielded a database with sufficient power to identify those patients at highest risk for a patent foramen ovale-related stroke recurrence who may have the greatest potential benefit from patent foramen ovale closure.

Secondary stroke prevention: patent foramen ovale, aortic plaque, and carotid stenosis

Stroke is the most debilitating cardiovascular event. It has a variety of causes that may be present simultaneously. In young or otherwise healthy people, the search for a patent foramen ovale (PFO) has become standard. In stroke of the elderly, atherosclerosis and atrial fibrillation are in the foreground but the PFO should not be ignored. The risk of a PFO-related stroke over time is controversial and so is its prevention by device closure. The association of proximal aortic plaques in arteries subtending the brain and stroke is considered strong, ignoring that it is as putative as that of the PFO. Statins can prevent progression of such plaques. Antiplatelet agents in asymptomatic and surgical endarterectomy in symptomatic patients or highly ulcerated lesions are the treatment of choice. Stenting with protection devices was shown competitive in selected patients.

Long-term propensity score-matched comparison of percutaneous closure of patent foramen ovale with medical treatment after paradoxical embolism

BACKGROUND

Patients with ischemic stroke or transient ischemic attack presumably related to patent foramen ovale (PFO) are at risk for recurrent cerebrovascular events. Differences in long-term clinical outcome were investigated among patients with percutaneous PFO closure and those who received medical treatment.

METHODS AND RESULTS

Between 1994 and 2000, 308 consecutive patients with cerebrovascular events presumably related to PFO underwent either percutaneous PFO closure (150 patients) or medical treatment (158 patients). Patients were followed up prospectively for up to 15 years. Seven patients were lost during follow-up. The primary outcome was a composite of stroke, transient ischemic attack, or peripheral embolism. We analyzed 103 propensity score-matched pairs of patients who underwent percutaneous PFO closure or medical treatment. At a median follow-up of 9 years, the primary composite outcome occurred in 11 patients slated to PFO closure (11%) and 22 patients slated to medical treatment (21%; hazard ratio=0.43; 95% confidence interval=0.20-0.94; P=0.033). The treatment effect was driven by a decrease in the risk of transient ischemic attack of 5% versus 14%, respectively (hazard ratio=0.31; 95% confidence interval=0.10-0.94; P=0.039). The risk of all-cause (6% in both groups) and cardiovascular (3% in both groups) mortality appeared to be identical.

CONCLUSION

In this long-term observational, propensity score-matched study, percutaneous PFO closure was more effective than medical treatment for the secondary prevention of recurrent cerebrovascular events among patients with PFO-related transient ischemic attack or stroke.

Microembolus detection by transcranial Doppler sonography: review of the literature

Transcranial Doppler can detect microembolic signals which are characterized by unidirectional high intensity increase, short duration, random occurrence, and a “whistling” sound. Microembolic signals have been detected in a number of clinical settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty), surgery (carotid, cardiopulmonary bypass, orthopedic), and in certain systemic diseases. Microembolic signals are frequent in large artery disease, less commonly detected in cardioembolic stroke, and infrequent in lacunar stroke. This article provides an overview about the current state of technical and clinical aspects of microembolus detection.

Long-Term Risk of Recurrent Stroke in Young Cryptogenic Stroke Patients with and without Patent Foramen Ovale

Background

Among patients with a patent foramen ovale and cryptogenic ischemic stroke, the long-term prognosis is unclear.

Aims

This study aims to estimate the recurrence rate in young cryptogenic stroke patients with and without patent foramen ovale.

Patients and methods

One hundred eighty-six cryptogenic stroke patients (aged 18–45 years) were prospectively followed for up to five-years. They were divided into two groups according to the echocardiographic presence of patent foramen ovale. All patients received aspirin (100mg/day) for secondary prevention.

Results

Mean age was 32·3 (standard deviation 7·9) years. During the mean follow-up of 66 months five patients with patent foramen ovale had recurrent strokes compared with 11 patients without patent foramen ovale. The average annual rate of recurrent cerebral ischemia was 1·1% and 1·6% for patients with and without patent foramen ovale, respectively. The recurrence rate did not increase with the presence of patent foramen ovale, atrial septal aneurysm or other variables. More than 60% of the reported cases achieved a good functional outcome.

Conclusions

Young patients with cryptogenic ischemic stroke with and without patent foramen ovale have a low recurrence rate in a long-term follow-up and most present a favorable outcome. Patent foramen ovale with or without atrial septal aneurysm did not increase the risk of recurrence.

The Risk of Paradoxical Embolism (RoPE) Study: developing risk models for application to ongoing randomized trials of percutaneous patent foramen ovale closure for cryptogenic stroke

BACKGROUND

Despite the diffusion into practice of percutaneous closure of a patent foramen ovale (PFO) in patients with cryptogenic stroke (CS), the benefits have not been demonstrated, and remain unclear. For any individual presenting with a PFO in the setting of CS, it is not clear whether the PFO is pathogenically-related to the index event or an incidental finding. Further, the overall rate of stroke recurrence is low in patients with CS and PFO. How patient-specific factors affect the likelihood that a discovered PFO is related to an index stroke or affect the risk of recurrence is not well understood. These probabilities are likely to be important determinants of the benefits of PFO closure in CS.

DESIGN/METHODS

The goal of the Risk of Paradoxical Embolism (RoPE) Study is to develop and test a set of predictive models that can identify those patients most likely to benefit from preventive treatments for PFO-related stroke recurrence, such as PFO closure. To do this, we will construct a database of patients with CS, both with and without PFO, by combining existing cohort studies. We will use this pooled database to identify patient characteristics associated with the presence (versus the absence) of a PFO, and to use this "PFO propensity" to estimate the patient-specific probability that a PFO was pathogenically related to the index stroke (Model #1). We will also develop, among patients with both a CS and a PFO, a predictive model to estimate patient-specific stroke recurrence risk based on clinical, radiographic and echocardiographic characteristics. (Model #2). We will then combine Models #1 and #2 into a composite index that can rank patients with CS and PFO by their conditional probability that their PFO was pathogenically related to the index stroke and the risk of stroke recurrence. Finally, we will apply this composite index to completed clinical trials (currently on-going) testing endovascular PFO closure against medical therapy, to stratify patients from low-expected-benefit to high-expected-benefit.

Patent foramen ovale and obstructive sleep apnoea: from pathophysiology to diagnosis of a potentially dangerous association

Patent foramen ovale and obstructive sleep apnoea are frequently encountered in the general population. Owing to their prevalence, they may coexist fortuitously; however, the prevalence of patent foramen ovale seems to be higher in patients with obstructive sleep apnoea. We have reviewed the epidemiological data, pathophysiology, and the diagnostic and therapeutic options for both patent foramen ovale and obstructive sleep apnoea. We focus on the interesting pathophysiological links that could explain a potential association between both pathologies and their implications, especially on the risk of stroke.

Transient monocular visual loss

Transient monocular visual loss is an important clinical complaint and has a number of causes, of which the most common is retinal ischemia. A practical approach is to perform a careful examination to determine whether there are any eye abnormalities that can explain the visual loss. Despite the transient nature of the symptom, there may be clues to the diagnosis on the examination even after the visual loss has recovered.

Prevention of Stroke in Patients with Patent Foramen Ovale

Patent foramen ovale is found in 24% of healthy adults and 38% of patients with cryptogenic stroke. This ratio and case reports indicate that patent foramen ovale and stroke are associated, probably because of paradoxical embolism. In healthy people with patent foramen ovale, embolic events are not more frequent than in controls, and therefore no primary prevention is needed. However, once ischaemic events occur, the risk of recurrence is substantial and prevention becomes an issue. Acetylsalicylic acid and warfarin reduce this risk to the same level as in patients without patent foramen ovale. Patent foramen ovale with a coinciding atrial septal aneurysm, spontaneous or large right-to-left shunt, or multiple ischaemic events potentiates the risk of recurrence. Transcatheter device closure has therefore become an intriguing addition to medical treatment, but its therapeutic value still needs to be confirmed by randomised-controlled trials.

Five-year experience with percutaneous closure of patent foramen ovale

Patent foramen ovale (PFO) has been implicated in the pathogenesis of cryptogenic stroke, arterial desaturation, decompression illness, and migraine headache (MH). This study evaluated the safety of percutaneous transcatheter PFO closure in patients with cryptogenic stroke, transient ischemic attack, or arterial desaturation. Additionally, symptomatic reduction in MH was determined after interatrial shunt closure. Of the 252 patients referred to the University of California, Los Angeles, with PFO, 131 underwent closure of the interatrial communication with a CardioSEAL (n = 30) or Amplatzer (n = 101) device. PFO morphology was evaluated with transesophageal echocardiography. Follow-up was conducted at 1 to 2 months with echocardiography, with clinical assessment annually thereafter. At an average follow-up of 30 months, there was no recurrence of any thromboembolic event (transient ischemic attack, stroke, or peripheral). There was a reduction in MH, defined as the complete resolution of headache or a >50% reduction in the number of headache days, in 85% of patients after PFO closure. Temporary problems after device implantation, including chest discomfort and palpitations, were reported in 23% of patients and occurred more frequently in patients with nickel hypersensitivity (p <0.05). In conclusion, transcatheter PFO closure is an effective and safe therapeutic modality in the prevention of thromboembolic events and MH associated with interatrial shunting in patients who present with cryptogenic stroke. Pending randomized, controlled trials are necessary to determine if this invasive approach is preferable to medical therapy for the prevention of recurrent stroke or as primary treatment for patients with MH.

Correlation or causation: Untangling the relationship between patent foramen ovale and migraine

Observational evidence from the literature has shown an association between migraine headaches and patent foramen ovale (PFO). This observation has led to hypotheses that could explain the etiology of migraines in those with a PFO, including right-to-left shunting of venous agents such as serotonin that are normally broken down in the pulmonary circulation. Further evidence suggests that closure of a PFO may improve migraine symptoms and serve as an effective treatment modality for migraines. Several randomized controlled double-blinded studies are underway that will more definitively establish the role of specific devices in PFO closure in those suffering from migraines.

Clinical significance of microembolus detection by transcranial Doppler sonography in cardiovascular clinical conditions

Transcranial Doppler can detect microembolic signals, which are characterized by unidirectional high intensity increase, short duration, and random occurrence, producing a "whistling" sound. Microembolic signals have been proven to represent solid or gaseous particles within the blood flow. Microemboli have been detected in a number of clinical cardiovascular settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty) and surgery (carotid, cardiopulmonary bypass). Despite numerous studies performed so far, clinical significance of microembolic signals is still unclear. This article provides an overview of the development and current state of technical and clinical aspects of microembolus detection.

Percutaneous closure of patent foramen ovale

AIM

To review the safety and efficacy of percutaneous closure of patent foramen ovale (PFO) in symptomatic patients without the use of general anaesthesia or echocardiographic guidance.

METHOD

All patients accepted for percutaneous PFO closure by our service from August 2002 to August 2004 were included. Patient demographics and clinical information were obtained from clinical records and by telephone interview. Follow-up outcomes recorded were recurrence of systemic thromboembolism, residual shunt, and change in pattern of migraines.

RESULTS

Forty consecutive adult patients, of whom 19 (48%) had an atrial septal aneurysm (ASA), underwent PFO closure using the Amplatzer occluder device with fluoroscopic guidance alone. Their mean age was 45 +/- 10 years (range 23-63 years) and 24 (60%) were male. The indications for closure were ischaemic stroke (n = 26), transient ischaemic attack (TIA) (n = 8), both stroke and TIA (n = 2), refractory hypoxia (n = 2), platypnoea-orthodeoxia (n = 1) and severe migraine with seizures (n = 1). Twenty patients suffered a single neurological event and 16 suffered >1 event, including six with only radiographic evidence of >1 event. Mean procedure time was 17.7 +/- 9.6 min and fluoroscopy time was 6.7 +/- 7.3 min. Implanted device sizes were 18 mm (n = 1), 25 mm (n = 37) and 35 mm (n = 2). In 33 patients, the procedure was performed as a day-case. No complications were encountered. No further neurological events occurred in 39 patients at a mean follow-up time of 11 +/- 7 months (3-25 months) nor was a significant shunt detected in the 34 who underwent follow-up echocardiography.

CONCLUSIONS

Percutaneous closure of PFO with or without ASA, under local anaesthesia and without echocardiographic guidance, is a safe and effective procedure which can be performed as a day-case. This has now become our standard clinical practice.

Antithrombotic Therapy for Stroke in Young Adults

Stroke in young adults is a markedly heterogeneous disease, and remains an understudied phenomenon. While advances are being made in our understanding of the pathophysiology of its underlying conditions, treatment concerns are controversial, and clinical trials are sorely lacking. This review presents an overview of some of the relevant management issues in hypercoagulable states, migraine, patent foramen ovale, vascular dissection and venous sinus thrombosis.

Offenes Foramen ovale, Vorhofseptumaneurysma und Hirninfarkt

The role of a patent foramen ovale (PFO) in stroke is still regarded as controversial, as is the optimal strategy of secondary prevention for such patients. The best available evidence is derived from case-control studies, which in all show a statistically significant relationship but cannot be judged as conclusive for methodologic reasons. Besides paradoxic embolism, different pathomechanisms of stroke due to abnormalities of the atrial septum are possible that can rarely be verified in clinical routine. While the risk of stroke recurrence seems to be low at least for younger patients, to date no definite recommendations for secondary prevention can be given. Several ongoing randomized clinical trials might increase the store of evidence in this topic over the next years. However, primary and secondary risk seem to be substantially increased for the combined defect of PFO and atrial septum aneurysm. To allow further risk stratification, other potentially important factors such as shunt size and coagulation disorders should be targeted in future studies.

Heart, brain, and mind: a case series of multifactorial ischemic strokes in children

Ischemic strokes in children, although generally rare events, are more prevalent than commonly believed and can adversely affect brain development. Ischemic strokes in children have been associated with various risk factors, including coagulation defects, cardiac anomalies, inborn errors of metabolism, infections, trauma, and even migraine headaches. We present four children with two or more of these risk factors, indicating multifactorial causes of strokes in children. Neuropsychologic testing in two of our cases also underscores cognitive decline as a result of recurrent strokes.

Surgical Closure of Combined Symptomatic Patent Foramen Ovale and Atrial Septum Aneurysm for Prevention of Recurrent Cerebral Emboli

BACKGROUND

Patients with patent foramen ovale (PFO) have an undefined but certainly considerable risk of repeated cerebral ischemia due to paradoxical embolism. Especially, if a cerebrovascular event has already occurred and the combination with an atrial septum aneurysm (ASA) is present this risk increases tremendously. The aim of this study was to demonstrate that surgical closure of PFO in combination with an ASA is safe and useful in preventing recurrent strokes.

METHODS

Ten patients with previous cerebral ischemia, proven by CT or MRI, and PFO in combination with an ASA were prospectively scheduled for surgical closure. Patients with extracardiac sources of embolic disease were excluded from this study. However, one patient suffered from a hypercoagulability syndrome.

RESULTS

All patients (mean age 35.5 +/- 19.1 years) underwent direct suture of the PFO and plication of the ASA with the aid of cardiopulmonary bypass and cardioplegic arrest (n = 3) or ventricular fibrillation (n = 7). Mean operation time was 123.1 +/- 20.2 minutes; mean bypass time was 34.5 +/- 9.9 minutes. There was no mortality or significant postoperative morbidity. Mean hospital stay was 5.1 +/- 1.5 days. During a follow-up of >4 years, no recurrent stroke or transient ischemic attack occurred and no patient received anticoagulation therapy.

CONCLUSION

Our data suggest that surgical closure of PFO in combination with ASA in patients with previous stroke is safe and efficacious to prevent recurrent strokes and avoids lifelong anticoagulation.

Stroke as a complication of congenital heart disease

Patent foramen ovale is a common finding in the general population. It is associated with an increased risk of stroke, but it may not have a significant effect on recurrent stroke risk in medically treated patients. Recently, many questions have arisen with respect to best treatment for preventing recurrent stroke. Some data from a clinical trial of anticoagulation compared with antiplatelet therapy support antiplatelet treatment for secondary prevention. There are not enough data currently to support surgical or percutaneous closure of patent foramen ovale for stroke prevention.

Patent foramen ovale in a cohort of young patients with cryptogenic ischemic stroke

OBJECTIVE: Although its role is a matter of debate, some studies described a higher prevalence of patent foramen ovale (PFO) and atrial septal aneurysm (ASA) in young stroke patients, with higher risk with PFO / ASA association (OR 4.96). The aim of this study was determine the prevalence of PFO and ASA in a cohort of cryptogenic ischemic stroke (IS) patients younger than 55 years and to follow-up after surgical or percutaneous endovascular closure (PEC). METHOD: In 21 months we identified all patients less than 55 years old with IS who were admitted to our hospital. Cryptogenic IS was considered if there is not an identifiably cause to cerebral ischemia. Transesophageal echocardiography (TEE) was performed in all patients. After interatrial septal abnormalities diagnosis, percutaneous device closure was offered to all. Patients were followed monthly and keeped with oral AAS or Clopidogrel. RESULTS: We identified 189 patients with IS and 32 were less than 55 years old (16.9%). In 29 the IS was cryptogenic. TEE was performed in all patients and some form of interatrial septal abnormality was identified in 12 (12/29 - 41.3%); 5 had a PFO and in 7 there was PFO plus ASA. Ten patients were submitted to PEC and 2 were submitted to surgical closure. In mid-term follow-up (28 months) no ischemic events occurred and 2 patients related disappearance of migraine symptoms. CONCLUSION: Our small series description is in accordance with other studies and suggests a possible relation between interatrial septal abnormalities and IS in a cohort of young patient.

Non-cardioembolic Mechanisms in Cryptogenic Stroke: Clinical and Diffusion-weighted Imaging Features

BACKGROUND

The role of several cardiogenic risk factors, including patent foramen ovale, in patients with cryptogenic stroke has been extensively studied. However, little attention has been paid to the role of non-cardioembolic causes of cryptogenic stroke. We therefore sought to identify the characteristics of cryptogenic stroke.

METHODS

We studied 832 patients with acute infarction in the middle cerebral arterial territory. We divided the patients into four subtypes: 402 with large artery atherosclerosis (LAA), 133 with cardioembolism, 182 with small arterial occlusion (SAO), and 115 with cryptogenic stroke. We compared risk factors and lesion patterns observed by diffusion-weighted imaging (DWI) between patients with cryptogenic stroke and those with stroke of other subtypes.

RESULTS

Both risk factors and DWI lesion patterns differed between the cryptogenic and cardioembolic groups (P<0.05). Risk factors for cryptogenic stroke were similar to those for the LAA and SAO groups. Similarly, DWI lesion patterns for cryptogenic stroke were similar to LAA patients. Large cortical infarcts on DWI were more common in the cardioembolic group than in the LAA or cryptogenic groups (P<0.001). In contrast, deep, non-lacunar (OR 5.02; 95% CI 2.68~9.40; P<0.001) and superficial perforator infarcts (OR 2.23; 95% CI 1.08~4.59; P=0.029) were independently associated with the cryptogenic group.

CONCLUSIONS

Our results indicate that non-cardioembolic causes, such as macro- and microangiopathy, are important mechanisms in the pathogenesis of cryptogenic stroke.

Pronóstico funcional tras un año de seguimiento en pacientes con infarto cerebral de causa desconocida y foramen oval permeable

BACKGROUND AND OBJECTIVE

The presence of patent foramen ovale (PFO) and atrioseptal aneurysm (ASA)has been described as a risk factor in cryptogenetic stroke. Patients with unknown origin stroke and PFO have less severe symptoms compared to the rest of cryptogenetic stroke patients. We evaluated the clinical situation in stroke patients with PFO and describe the factors predictive of a better outcome after a year.

PATIENTS AND METHOD

1118 patients between 18 and 70 years old were evaluated, and 223 were classified as having cryptogenetic stroke. Our protocol Included transcranial Doppler, a transesophageal echocardiography (TEE) and a cranial RM. We used the NIH Stroke Scale (NIHSS) to evaluate the clinical situation, and the modified Ranking Scale for the functional outcome.

RESULTS

A total of 117 patients had all inclusion criteria. 66 (56.4%) showed a PFO. We observed a younger age, a higher percentage of females (48.4% in PFO vs. 25.5% in no-PFO) and less risk factors in PFO patients, except for migraine (24.6% in PFO vs. 5.9% in no-PFO; p = 0.01). PFO patients had less severe strokes (NIHSS: 3--median--in PFO vs. 5 in no-PFO; p = 0.010) and a lower grade of sequelae (p 0.024). Worse outcome was related to male, initial neurological evaluation (NIHSS) and presence of ASA. After a logistic regression, only the initial clinical situation (NIHSS) and the presence of ASA were associated with sequelae.

CONCLUSIONS

PFO patients showed a less severe stroke and better functional outcome. The initial neurological involvement and the presence of ASA are predictive of the clinical situation after a year.

Percutaneous patent foramen ovale closure

This article discusses percutaneous patent foramen ovale closure.

Comparison of medical treatment with percutaneous closure of patent foramen ovale in patients with cryptogenic stroke

OBJECTIVES

The purpose of this study was to compare the efficacy of medical treatment with percutaneous closure of patent foramen ovale (PFO).

BACKGROUND

Patients with cryptogenic stroke and PFO are at risk for recurrent cerebrovascular events.

METHODS

We compared the risk of recurrence in 308 patients with cryptogenic stroke and PFO, who were treated either medically (158 patients) or underwent percutaneous PFO closure (150 patients) between 1994 and 2000.

RESULTS

Patients undergoing percutaneous PFO closure had a larger right-to-left shunt (p < 0.001; 95% confidence interval [CI] 1.38 to 3.07) and were more likely to have suffered more than one cerebrovascular event (p = 0.03; 95% CI 1.04 to 2.71). At four years of follow-up, percutaneous PFO closure resulted in a non-significant trend toward risk reduction of death, stroke, or transient ischemic attack (TIA) combined (8.5% vs. 24.3%; p = 0.05; 95% CI 0.23 to 1.01), and of recurrent stroke or TIA (7.8% vs. 22.2%; p = 0.08; 95% CI 0.23 to 1.11) compared with medical treatment. Patients with more than one cerebrovascular event at baseline and those with complete occlusion of PFO were at lower risk for recurrent stroke or TIA after percutaneous PFO closure compared with medically treated patients (7.3% vs. 33.2%; p = 0.01; 95% CI 0.08 to 0.81, and 6.5% vs. 22.2%; p = 0.04; 95% CI 0.14 to 0.99, respectively).

CONCLUSIONS

Percutaneous PFO closure appears at least as effective as medical treatment for prevention of recurrent cerebrovascular events in cryptogenic stroke patients with PFO. It might be more effective than medical treatment in patients with complete closure and more than one cerebrovascular event.

Does transcatheter closure of patent foramen ovale really "shut the door?" A prospective study with transcranial Doppler

BACKGROUND AND PURPOSE

Transcatheter closure of patent foramen ovale (PFO) is increasingly being performed and monitored with transthoracic or transesophageal echocardiography, whereas contrast-enhanced transcranial Doppler (ce-TCD), which probably represents the most suitable tool to quantify right-to-left shunt (RLS) in the brain vessels, has been systematically overlooked. Our goal is to prospectively assess efficacy and safety of PFO transcatheter closure using ce-TCD.

METHODS

A total of 140 consecutive patients (mean age, 46+/-13 years; male/female ratio, 63/77) with PFO-related large RLS and no other recognized cause of focal cerebral ischemia underwent transcatheter closure. TCD was done preoperatively and 1 month after the procedure in all patients, after 3 months in 120, after 6 months in 112, and after 1 year in 104 patients.

RESULTS

Implantation was successful in all patients. During Valsalva strain, a large shunt was still detectable in 31 of 140 (22%), 15 of 120 (13%), 9 of 112 (8%), and 9 of 104 (9%) patients at the 1-, 3-, 6-, and 12-month visits, respectively. Periprocedural and postprocedural complications included atrial fibrillation in 8% and scintillating scotomata in 6% of patients. During the 1-year follow-up period, only 1 transient ischemic attack was recorded in a patient with paroxysmal atrial fibrillation and complete PFO closure.

CONCLUSIONS

Transcatheter PFO closure in patients with cryptogenic stroke and large RLS may be less successful than reported previously. TCD appears the ideal tool to follow up the closure process and to identify early, during follow-up, those patients who will be left with a significant shunt. Atrial fibrillation is more common than believed previously and may underlie the occurrence of further cerebrovascular events despite complete PFO closure. Irritative visual phenomena may occur as a consequence of nickel toxicity.

Treatment of recurrent stroke and pulmonary thromboembolism with percutaneous closure of a patent foramen ovale and placement of inferior vena cava filter

The association between recurrent episodes of pulmonary embolism, stroke, and congenital anomalies of the clotting system features a condition of increased risk of recurrences despite anticoagulant therapy. We report the successful management of this association with percutaneous closure of the foramen ovale and placement of an inferior caval vein filter.