Comparison of atrial septal defect and patent foramen ovale in cryptogenic strokes.

OBJECTIVES: Paradoxical embolism from right-to-left shunt through atrial septal defect (ASD) and patent foramen ovale (PFO) is a well-accepted cause of "cryptogenic" strokes (CS). To better understand the pathogenic role of ASD, we compared ASD patients with CS having a high and low likelihood of being PFO-related. METHODS: In the Acute Stroke Registry and Analysis of Lausanne, we calculated prevalence of PFO and ASD in CS patients undergoing echocardiography, and calculated odds ratios (OR) when compared to non-CS. Using the Risk of Paradoxical Embolism (RoPE) score, we divided CS PFO patients in high (HL-PFO, RoPE 8-10) and low-likelihood (LL-PFO, RoPE 0-4) PFO-related stroke. We then performed univariate comparison of epidemiological, clinical and radiological variables of ASD patients with both PFO groups. RESULTS: Among all CS, prevalence of ASD and PFO were 1.3% and 36.8% respectively. When compared to non-CS, ASD and PFO were associated with CS (OR of 5.2, CI= 1.6-16.6, and 2.8, CI= 2.1-3.8). Compared with HL-PFO, ASD patients were older, more often female, had more cardiovascular risk factors and silent strokes. Compared with LL-PFO, ASD patients were younger, more often female, and had less risk factors. No differences were found for clinical and radiological characteristics and clinical outcome. CONCLUSION: ASD is a rare stroke risk factor for CS. Since characteristics of such patients lie in-between high and low-likelihood paradoxical PFO-strokes, a thorough work-up for other stroke mechanisms is warranted. Individual evaluation of the likelihood of the ASD being causative for stroke may be preferable over routine ASD closure.

Predictors of recurrent cerebral ischemia after patent foramen ovale closure: A single center observational study.

OBJECTIVES: Transcatheter patent foramen ovale closure lowers recurrent stroke in patients with cryptogenic stroke or transient ischemic attack with an indication for closure. However, the incidence of recurrent stroke is not negligible and underlying pathophysiology remains largely unknown. We sought to evaluate the prevalence of recurrent ischemic neurological events and to assess its predictors after transcatheter patent foramen ovale closure. METHODS: We enrolled consecutive patients who underwent patent foramen ovale closure for secondary prevention of neurological ischemic events at the University Hospital of Parma between 2006 and 2021. Clinical and procedure-related features were collected for each patient. The incidence of recurrent ischemic neurological events was assessed at follow-up. RESULTS: We enrolled a total of 169 patients with mean Risk of Paradoxical Embolism score at hospital admission of 6.4 ± 1.5. The primary indication was previous cryptogenic stroke (94 [55.6 %] subjects), followed by transient ischemic attack (75 [44.4 %]). Among patients with complete outcome data (n= 154), after a median follow-up of 112 months, recurrent cerebral ischemia occurred in 13 [8.4 %], with an annualized rate of 0.92/100 patients. The presence of obesity [OR 5.268, p = 0.018], Risk of Paradoxical Embolism score < 7 [OR 5.991, p = 0.035] and migraine [OR = 5.932 p = 0.012] were independent positive predictors of recurrent stroke/ transient ischemic attack after patent foramen ovale closure. CONCLUSIONS: The presence of obesity, Risk of Paradoxical Embolism score < 7 and migraine were independent positive predictors of recurrent ischemic neurological events after patent foramen ovale closure.

Potential Embolic Sources in Embolic Stroke of Undetermined Source Patients with Patent Foramen Ovale.

INTRODUCTION: A patent foramen ovale (PFO) may coexist with other potential embolic sources (PESs) in patients with embolic stroke of undetermined source (ESUS), leading to difficulty in attributing the stroke to either the PFO or other PESs. We aimed to investigate the prevalence and predictors of concomitant PESs in ESUS patients with PFOs. METHODS: A retrospective cohort study was conducted in a tertiary stroke centre. Consecutive patients with ESUS and a concomitant PFO admitted between 2012 and 2021 were included in the study. Baseline characteristics and investigations as a part of stroke workup including echocardiographic and neuroimaging data were collected. PESs were adjudicated by 2 independent neurologists after reviewing the relevant workup. RESULTS: Out of 1,487 ESUS patients, a total of 309 patients who had a concomitant PFO with mean age of 48.8 ± 13.2 years were identified during the study period. The median Risk of Paradoxical Embolism (RoPE) score for the study cohort was 6 (IQR 5-7.5). Of the 309 patients, 154 (49.8%) only had PFO, 105 (34.0%) patients had 1 other PES, 34 (11.0%) had 2 PES, and 16 (5.2%) had 3 or more PES. The most common PESs were atrial cardiopathy (23.9%), left ventricular dysfunction (22.0%), and cardiac valve disease (12.9%). The presence of additional PESs was associated with age ≥60 years (p < 0.001), RoPE score ≤6 (p ≤0.001), and the presence of comorbidities including diabetes mellitus (p = 0.004), hypertension (p≤ 0.001), and ischaemic heart disease (p = 0.011). CONCLUSION: A large proportion of ESUS patients with PFOs had concomitant PESs. The presence of concomitant PESs was associated with older age and a lower RoPE score. Further, large cohort studies are warranted to investigate the significance of the PES and their overlap with PFOs in ESUS.

Ischemic Stroke Secondary to Paradoxical Embolism Through a Pulmonary Arteriovenous Malformation: Case Report and Review of the Literature.

Paradoxical embolism due to isolated pulmonary arteriovenous malformation (AVM) is an uncommon cause of ischemic stroke, with the majority occurring in patients who have not yet been diagnosed with their malformation. We report a 32-year-old man who presented with an abrupt onset of right facial weakness and expressive aphasia. Brain magnetic resonance imaging revealed an acute infarct in the left middle cerebral artery territory and chronic infarcts in the bilateral cerebellar hemispheres. A cardioembolic mechanism was initially considered in the setting of perimyocarditis diagnosed a few months earlier. Transthoracic and transesophageal echocardiograms revealed high volume right to left shunting, but no septal defects. A pulmonary AVM was confirmed with computed tomography angiography and fistualization was successfully treated with embolization. This report highlights a case of undiagnosed pulmonary AVM leading to recurrent paradoxical emboli to the brain. We review the epidemiology, pathophysiology, and management of pulmonary AVMs in relation to stroke risk.

Patent foramen ovale (PFO): is there life before death in the presence of PFO?

Patent foramen ovale (PFO) is an embryologic remnant with incomplete postnatal adhesion of the cardiac atrial septum primum and secundum. After birth, the prevalence of PFO decreases from about 35% at young to approximately 20% at old age. PFO has been associated with numerous conditions such as decompression illness in divers, migraine, high-altitude pulmonary oedema, cerebrovascular and coronary ischaemia, and obstructive sleep apnoea syndrome. PFO is the cause of intermittent atrial right-to-left shunt, and it can be the source of cardiac paradoxical embolism. So far, randomized controlled trials have not documented a reduced rate of cerebrovascular recurrent events in patients receiving PFO device closure as compared to those on medical treatment. The purpose of this article was to critically evaluate evidence on the pathophysiologic, clinical as well as prognostic relevance of PFO.

Prevalence of Pelvic Vein Pathology in Patients with Cryptogenic Stroke and Patent Foramen Ovale Undergoing MRV Pelvis.

BACKGROUND: A substantial proportion of ischemic strokes has no any identified underlying cause. Notably, the prevalence of a patent foramen ovale (PFO) is increased in cryptogenic stroke (CS) populations, which may serve as a conduit for paradoxical emboli originating from deep vein thrombosis (DVT) including the pelvic veins. Yet, there are no published guidelines for the assessment of pelvic veins as part of the stroke workup and few studies have systematically investigated pelvic veins as a potential source for paradoxical emboli in CS patients. Further, there is a relative paucity of data regarding pelvic DVT in CS and results have been conflicting. Hence, we sought to determine the prevalence of pelvic DVT in select CS patients with PFO who underwent magnetic resonance venography (MRV). METHODS: We retrospectively identified patients (n = 50) who underwent contrast-enhanced pelvic MRV at the discretion of the treating physician for the evaluation of CS in the presence of a PFO during hospitalization at a single academic stroke center between January 2011 through December 2013. Multivariable logistic regression analyses were used to assess for factors independently associated with the presence of an abnormal MRV pelvis. RESULTS: Patients (47 ± 13 years of age) had MRV performed 4 ± 3 days after their incident stroke. Nine patients had an abnormal MRV (18%). Of these, four (8%) had pelvic vein thrombosis and 5 (10%) a May-Thurner anatomic variant. All patients with pelvic DVT were subsequently anticoagulated with warfarin (none had abnormal hypercoagulability testing). Clinical clues suggesting paradoxical embolism were present in as many as 40% of patients. On multivariable logistic regression, a history of any risk factors predisposing to DVT (OR 6.7; coefficient 1.9; BCa 95% CI 0.08-20.2; p = 0.014) as well as the number of predisposing risk factors (OR 3.9; coefficient 1.4; BCa 95% CI 0.25-4.2; p = 0.005) predicted the presence of pelvic vein pathology on MRV. CONCLUSION: We demonstrate a relatively high prevalence of pelvic DVT among select CS patients emphasizing the importance of considering the pelvic veins as a potential source for emboli particularly in the presence of risk factors known to predispose DVT. Because patients were included at the treating physician's discretion, our results reflect 'real-life' practice. Our results may be of clinical importance as inclusion of pelvic vein imaging in CS patients with PFO had impactful therapeutic and nosologic implications. Further study is needed to define patients most likely to benefit from pelvic vein imaging.

Retinal arterial occlusion and patent foramen ovale: A case study-based review.

PURPOSE: To identify all reported cases of retinal artery occlusion (RAO) associated with patent foramen ovale (PFO) in the literature and present a similar case of CRAO from our clinic. METHODS: PubMed database was searched for studies reporting RAO in individuals with PFO. Relevant data were tabulated and reviewed. We estimated each case's Risk of Paradoxical Embolism (RoPE) score. RESULTS: 23 cases of CRAO (n=10; including ours), BRAO (n=10), and CILRAO (n=3) were reviewed. Most cases were under 50 years of age (78.3%). The reported predisposing factors were: hypertension (26.1%), migraine (17.3%), smoking (13.0%), recent immobilization (13.0%), strenuous exertion (8.7%), pregnancy (8.7%), and diabetes (4.3%). A high RoPE score (≥7; suggestive of paradoxical embolism via PFO) was estimated for 71.4% of patients. In most cases, the neurological and cardiovascular examinations, laboratory studies, and imaging were unremarkable, except for the PFO±atrial septal aneurysm (present in 21.7%). In only 28.6% of cases, transthoracic echocardiography (TTE) (± saline contrast) could visualize the PFO; transesophageal echocardiography (TEE) was necessary to detect the PFO in 71.4%. Approximately one-half of the patients underwent percutaneous closure of the PFO; no complications or subsequent acute ischemic events ensued. The visual prognosis was poorer for CRAO than for BRAO or CILRAO. CONCLUSION: Timely diagnosis, acute management, and ensuring urgent initiation of stroke workup in cases with RAO or transient monocular vision loss are crucial. Clues to a possible paradoxical embolism as the cause include the absence of known cardiovascular risk factors, young age, migraine, recent immobility, vigorous exercise, and pregnancy.

Wake-up stroke and TIA due to paradoxical embolism during long obstructive sleep apnoeas: a cross-sectional study.

BACKGROUND AND PURPOSE: Long obstructive sleep apnoeas (LOSAs) can cause brain ischaemia through paradoxical embolism since they can lead to right to left shunting (RLSh) but this has never been assessed as a risk factor for stroke. We investigated whether the combination of LOSA and RLSh is associated with ischaemic stroke or transient ischaemic attack (TIA) on waking (wake-up stroke). METHODS: We prospectively considered patients aged over 18 years, admitted to 13 stroke units for acute ischaemic stroke or TIA. Patients had to be able to give consent, to specify whether the event occurred on waking, and to cooperate sufficiently to undergo contrast transcranial Doppler examination and cardiorespiratory sleep study within 10 days of the onset of symptoms. Single LOSA events, lasting 20 s or more, were considered a possible harbinger of RLSh. RESULTS: Between April 2008 and March 2010, 335 patients (109 women; 61 TIA, mean age 64 years) were enrolled; 202 (60%) had at least one LOSA and 116 (35%) a RLSh; 69 (21%) had both. There were significantly more wake-up strokes/TIAs in subjects with RLSh plus LOSA than those without this association (27/69 vs 70/266; OR 1.91, controlled for age, sex, hypertension, diabetes, atrial fibrillation, antithrombotic therapy; 95% CI 1.08 to 3.38; p=0.03). No other risk factor was associated with an increase in the incidence of events on waking. CONCLUSIONS: The study suggests that the combination of LOSA and RLSh could be a new major, potentially treatable risk factor for cerebrovascular ischaemic events.

Recurrent events after percutaneous closure of patent foramen ovale.

OBJECTIVES: To determine the incidence of symptomatic recurrent embolic events after patent foramen ovale (PFO) closure and potential causes for these events. BACKGROUND: It is well-known that cerebral or other embolic events may occur after PFO closure. METHODS: This is a retrospective analysis of consecutive patients who underwent PFO closure for secondary prevention of embolic events at a single institution. RESULTS: 1,930 patients (mean age of 50 ± 13.3 years) underwent transcatheter PFO closure. Complete closure occurred in 92%. The annual recurrence rate of embolic events before PFO closure was 22.4% (785 events in 3,497 patient-years). During follow-up (mean 39 months), 63 recurrent events were documented: 25 strokes, 36 transient ischemic attacks (TIAs), and 2 peripheral embolic events. The overall annual recurrence rate after the procedure was 1% per year (63 events in 6,211 patient-years). The majority of events occurred in patients without residual shunts (54/63). There was no significant association between the presence of a residual shunt and recurrent events [hazard ratio (HR) 1.7; 95% confidence interval (CI) 0.8-3.6, P = 0.16]. The most common cause for recurrent events was atherosclerosis. Nine out of 63 events were considered likely or possible paradoxical embolism due to residual shunt [stroke (2), TIA (5), and peripheral embolism (2)]. After PFO closure, the annual rate of events potentially related to paradoxical embolism was 0.14% (9 events in 6,211 patient-years). CONCLUSION: The incidence of symptomatic embolic events after PFO closure is low. Most recurrent events are related to coexistent conditions associated with thromboembolic risk rather than residual shunts.

[Ischemic stroke associated with patent foramen ovale: hospital database analysis]. / Ishemicheskii insul't, assotsiirovannyi s otkrytym oval'nym oknom: analiz dannykh gospital'nykh registrov.

OBJECTIVE: To analyze clinical and instrumental characteristics of patients with ischemic stroke (IS) due to paradoxical embolism according to the data of hospital registers of Moscow and Perm. MATERIAL AND METHODS: A comprehensive study of 114 patients, aged 18 to 55 years, with IS by the mechanism of paradoxical embolism was carried out. All patients underwent clarification of the cause of IS (electrocardiography, ultrasound scanning of the brachiocephalic arteries, CT or MRI of the brain, CT or MR angiography, transthoracic and/or transesophageal echocardiography). The presence of right-left shunt blood flow (RLS) was confirmed by transcranial dopplerography with a bubble test. The clinical significance of patent foramen ovale (PFO) was assessed according to The PFO-Associated Stroke Causal Likelihood Classification System (PASCAL). RESULTS: Clinical and instrumental characteristics of patients with IS due to paradoxical embolism were obtained from two hospital registries. In both groups, the leading trigger for the development of IS was the Valsalva phenomen (>20%), the share of other provoking factors did not exceed 10%. Significant differences between the analyzed groups related to the ultrasonic characteristics of RLS/PFO: patients with a grade 4 shunt predominated in the Research Center of Neurology (RCN) population, while patients with a grade 3 shunt predominated in the City Clinical Hospital (CCH) №4 group. At the same time, there were twice as many patients with aneurysm of the interatrial septum in the CCH №4 group. In accordance with the PASCAL classification, in 93% of RCN patients, PFO can be considered as a probable cause of IS, while in the CCH No. 4 group, a probable causal relationship was traced only in 51% of cases, in 18% of patients, the role of an anomaly in the development of stroke was unlikely. CONCLUSION: The analysis showed that the primary screening of RLS in a regional vascular center allows classifying PFO as a probable cause of IS in only half of the patients. For a more accurate selection of patients for whom endovascular occlusion of the PFO will be most effective, an in-depth examination in a specialized hospital is recommended.

Sex Differences in Patients With Cryptogenic Cerebrovascular Events Undergoing Transcatheter Closure of Patent Foramen Ovale.

Background Scarce data exist on sex differences in patients with cryptogenic cerebrovascular events undergoing patent foramen ovale (PFO) closure. This study aimed to determine the sex differences in clinical profile, procedural characteristics, and long-term outcomes of patients with cryptogenic cerebrovascular events undergoing PFO closure. Methods and Results A retrospective cohort was used, including 1076 consecutive patients undergoing PFO closure because of a cryptogenic cerebrovascular event. Patients were divided into 2 groups: 469 (43.6%) women and 607 (56.4%) men. The median follow-up was 3 years (interquartile range, 2-8 years). Women were younger (46±13 versus 50±12 years; P<0.01) and had a higher risk of paradoxical embolism score (6.9±1.7 versus 6.6±1.6; P<0.01). Procedural characteristics and postprocedural antithrombotic therapy were similar. At follow-up, there were no differences in atrial fibrillation (women versus men: 0.47 versus 0.97 per 100 patient-years; incidence rate ratio [IRR], 0.55 [95% CI, 0.27-1.11]; P=0.095; adjusted P=0.901), stroke (0.17 versus 0.07 per 100 patient-years; IRR, 2.58 [95% CI, 0.47-14.1]; P=0.274; adjusted P=0.201), or transient ischemic attack (0.43 versus 0.18 per 100 patient-years; IRR, 2.58 [95% CI, 0.88-7.54]; P=0.084; adjusted P=0.121); nevertheless, women exhibited a higher incidence of combined ischemic cerebrovascular events (0.61 versus 0.26 per 100 patient-years; IRR, 2.58 [95% CI, 1.04-6.39]; P=0.041; adjusted P=0.028) and bleeding events (1.04 versus 0.45 per 100 patient-years; IRR, 2.82 [95% CI, 1.41-5.65]; P=0.003; adjusted P=0.004). Conclusions Compared with men, women with cryptogenic cerebrovascular events undergoing PFO closure were younger and had a higher risk of paradoxical embolism score. After a median follow-up of 3 years, there were no differences in stroke events, but women exhibited a higher rate of combined (stroke and transient ischemic attack) cerebrovascular events and bleeding complications. Additional studies are warranted to clarify sex-related outcomes after PFO closure further.

Paradoxical coronary embolism, a rare cause of acute myocardial infarction on positive pressure ventilation.

A 65-year-old man developed respiratory failure and was admitted to the Intensive Care Unit for positive pressure ventilation and antibiotic and antifungal therapy.There was a sudden deterioration with chest pain, worsening hypoxia and hypotension. Serial electrocardiograms showed new onset right bundle-branch block with developing anterior ST-segment elevation. An urgent coronary angiogram revealed acute occlusion of the left anterior descending artery with a single large distinct thrombus, which was successfully removed with an aspiration catheter. A presumptive diagnosis of paradoxical coronary embolus was made. A short review is provided of this relatively rare clinical entity which has the potential to present in intensive care patients who have an underlying intra-cardiac defect and require positive pressure ventilation. This case emphasises the importance of being aware of less common causes of acute clinical deterioration and electrocardiographic changes in the ventilated patient.

Outcomes Following Patent Foramen Ovale Percutaneous Closure According to the Delay From Last Ischemic Event.

BACKGROUND: Randomised controlled trials evaluating percutaneous closure of patent foramen ovale (PFO) have included only patients with a recent embolic event. We aimed to evaluate outcomes after percutaneous PFO closure according to the delay from the last embolic episode. METHODS: This international ambispective cohort included consecutive patients from 2 centres in France and Canada undergoing PFO closure for secondary prevention of a paradoxical embolic event. The primary end point was the composite of stroke or transient ischemic attack (TIA). A logistic regression model was used to evaluate determinants of late PFO closure procedures. RESULTS: A total of 1179 patients (mean age 49 ± 12.7 years; 44.4% female) underwent PFO closure from 2001 to 2021. The median delay from last embolic event to procedure was 6.0 (interquartile range 3.4-11.2) months. The determinants of late PFO closure procedure were the centre (France vs Canada; adjusted odds ratio [aOR] 1.65, 95% confidence interval [CI] 1.25-2.19), year of procedure (since 2018 vs before 2018; aOR 1.43, 95% CI 1.08-1.90), female sex (aOR 1.63, 95% CI 1.28-2.07), and lower risk of paradoxical embolism score (aOR 1.10, 95% CI 1.03-1.19). After a median follow-up of 2.61 (1.13-7.25) years, the incidence rate of first stroke or TIA did not differ between early and late PFO procedures, with 0.51 vs 0.29 events per 100 patient-years, respectively (incidence rate ratio 1.74, 95% CI 0.66-5.08; P = 0.24), and the timing of PFO closure was not associated with the occurrence of stroke or TIA in univariate analysis (hazard ratio 0.54, 95% CI 0.22-1.34) for late vs early closure). CONCLUSIONS: This analysis provides indirect evidence that the delay from the last ischemic event does not affect outcomes after PFO closure for secondary prevention.

Transcatheter Closure of Patent Foramen Ovale in Patients With Peripheral (Noncerebrovascular) Embolism.

OBJECTIVES: Scarce data exist on noncerebrovascular peripheral embolism (NCPE) patients undergoing transcatheter patent foramen ovale (PFO) closure. The objectives of this study were to determine the clinical and procedural characteristics, and long-term outcomes of patients with NCPE undergoing transcatheter PFO closure. METHODS: This was a multicenter study including 1136 consecutive patients who underwent PFO closure after a thromboembolic event. Patients were divided into 2 groups according to the type of event leading to PFO closure, ie, cerebrovascular event (CVE, n = 1099 [96.7%]) and NCPE (n = 37 [3.3%]). The median follow-up was 3 years (interquartile range, 1-8), with follow-up complete in 98%. RESULTS: Patients in the NCPE group exhibited higher rates of prior or concomitant pulmonary embolism (29.7% vs 3.4%; P<.001), and prior myocardial infarction (24.3% vs 1.8%; P<.001). Most NCPE events were located in the limbs (41%), followed by coronary (27%) and renal/splenic/mesenteric arteries (12%). PFO closure was successful in all patients, with a low complication rate (<1%) in both groups. NCPE patients were more frequently treated with anticoagulation following PFO closure (63% vs 13%; P<.001). There were no differences between NCPE and CVE groups in death (0 per 100 patient years vs 0.4 per 100 patient-years; P=.53) or cerebrovascular events (1.3 per 100 patient-years vs 0.4 per 100 patient-years; P=.15) at follow-up. CONCLUSIONS: Patients with NCPE events undergoing PFO closure exhibited differential baseline characteristics compared with patients with CVEs; limbs and coronary arteries were the most frequent NCPE location. PFO closure results and long-term outcomes were similar to their CVE counterparts, with a very low rate of recurrent thromboembolic events. Further studies are needed in this population.

Prevalence of Patent Foramen Ovale in North Indian Cryptogenic Young Strokes.

Background: : Strokes of the undetermined cause or cryptogenic strokes (CS) account for 30-40% of ischemic strokes. Paradoxical embolism secondary to patent foramen ovale (PFO) may be associated with CS. Transcranial Doppler (TCD) with bubble contrast is a noninvasive bedside tool for diagnosis of right-to-left shunt (RLS) with high sensitivity and specificity. Data on the prevalence of PFO in CS in India are lacking. We determined the prevalence of RLS likely secondary to PFO in cryptogenic young strokes of the north Indian population using TCD with bubble contrast. Patients and Methods: : In this hospital-based prospective cross-sectional study, TCD with bubble contrast was performed in 57 young (age 15 > 45 years) CS and 50 healthy controls for the detection of RLS. The risk of paradoxical embolism (RoPE) score was calculated from various variables such as age, presence of cortical stroke on neuroimaging, and absence of vascular risk factors. Results: : 57 young CS and 50 healthy controls were recruited. TCD with bubble contrast was positive in 31% cases vs 6% in controls (P = 0.001). All patients with TCD positive for RLS had superficial cortical infarcts (P = 0.03). The median RoPE score of our patients was 9 (range: 7-10). Conclusions: : There is a high prevalence of RLS likely secondary to PFO in cryptogenic young strokes in north India. TCD with bubble contrast is an excellent bedside tool for the detection of RLS.

[Changes in paradoxical emboly readiness in divers with open oval window of the interatrial septum].

AIM: To study development of paradoxical emboly readiness (PER) in the process of diving. MATERIAL AND METHODS: Examination and observation covered 46 inexperienced divers (beginning divers--BD), 51 experienced divers (diving experience more than 3 years, ED) and 98 healthy individuals not interested in diving. The examinees were follow-up for 20 years. All of them had no organic cardiovascular pathology. PER was detected by the method of imitation modeling of underwater emboly using prolonged infusion contrast echocardiography (PICE) with hydrogen peroxide solution. The intensity of right-left interatrial bypass (RLIAB) was determined by the number of microblebs penetrating in PICE in the left heart. In the BD group PICE was made each 3 years of diving experience, in ED group--each 3-5 years of further diving experience. RESULTS: Diving leads to activation of RLIAB, the number of divers with PER increases. Bypass and PER intensity grows in BD group. In ED group PER increased but RLIAB changed insignificantly. CONCLUSION: Our investigation confirms unfavourable effects of diving on RLIAB of blood in persons with open oval window (OOW) enhancing PER. Further investigations should be made on effects of diving on hemodynamic disorders due to OOW.

Advances and Ongoing Controversies in Patent Foramen Ovale Closure and Cryptogenic Stroke.

Up to a third of strokes are cryptogenic. The prevalence of patent foramen ovale (PFO) in patients with cryptogenic stroke is higher than in individuals with stroke of known origin. It has been proposed that some cryptogenic strokes can be caused by paradoxic embolism across a PFO. The treatment of PFO includes medical treatment with antithrombotic agents and percutaneous PFO closure. There is limited evidence to support PFO closure in unselected cases of cryptogenic stroke. However, large randomized clinical trials confirmed the superiority of transcatheter PFO closure compared with medical treatment in young patients with cryptogenic stroke.

Stroke in Pregnancy: A Multidisciplinary Approach.

Pregnancy confers a substantially increased risk of stroke, especially during the third trimester and until 6 weeks postpartum. Hypertensive disorders of pregnancy and gestational hypercoagulability are important contributors to obstetric stroke. Preeclampsia and eclampsia confer risk for future cardiovascular disease. Hemorrhagic stroke is the most common type of obstetric stroke. Ischemic stroke can result from cardiomyopathy, paradoxical embolism, posterior reversible encephalopathy, reversible cerebral vasoconstriction syndrome, and dissections. Cerebral venous sinus thrombosis is a frequent complication of pregnancy.

Patent foramen ovale and cryptogenic stroke: a matter of age?

A patent foramen ovale (PFO) enables a right-to-left shunt in about a quarter of the population. The marked association between cryptogenic stroke and PFO supports the hypothesis that paradoxical embolism could be a relevant cause of stroke. Although this association has been described in several studies for patients <55 years of age, only limited data are available on the role of PFO in older patients. Recent studies, however, have also shown a significant association between cryptogenic stroke and PFO in patients >55 years of age. The relationship is especially marked in the presence of atrial septum aneurysm (ASA). This finding is in accordance with previous reports indicating that PFO and concomitant ASA is a high-risk feature. Factors promoting paradoxical embolism, such as deep vein thrombosis (DVT) and elevated right-heart pressure, are more frequently encountered in older than in younger patients. Independent of age, contrast-enhanced transthoracic and transesophageal echocardiography are the methods of choice for the detection and imaging of PFO and atrial septal aneurysm. Transcranial Doppler can be used as a screening method in patients with cryptogenic stroke to detect a right-to-left shunt. Proof of DVT strongly supports the suspicion of paradoxical embolism and should lead to oral anticoagulation. If paradoxical embolism is suspected without proof of DVT, both drug therapy with aspirin or warfarin and percutaneous closure of the PFO are available as therapeutic options. Recent studies have shown that percutaneous closure can be performed safely and with a low rate of recurrence both in older and younger patients. Thus far, however, there is no clear-cut evidence of superiority for either therapeutic strategy.

Characteristics of adult patients with atrial septal defects presenting with paradoxical embolism.

BACKGROUND: The association between patent foramen ovale (PFO), atrial septal aneurysm, and cryptogenic stroke due to paradoxical embolism has been established. The correlation between atrial septal defect (ASD) in adults and paradoxical embolism is less well defined. METHODS: We examined our single center experience with 329 adult patients undergoing percutaneous device closure of interatrial communication defects to identify clinical and morphologic differences among adult patients with ASDs who presented with or without paradoxical embolism. Comparison was made with patients with PFO. RESULTS: Although a significant left-to-right shunt was the predominant indication for ASD closure, 20 patients (14%) presented with a paradoxical embolism. These patients tended to be younger and had smaller defects (both by size and shunt ratio) than ASD patients without paradoxical embolism, and were more likely to be female than PFO patients. CONCLUSIONS: The incidence of adult patients with ASD who presented with paradoxical embolism is higher than expected and suggests that this diagnosis should be considered in patients with cryptogenic stroke.