Eustachian valve, interatrial shunt, and paradoxical embolism

The Covert Impact of Chiari Network and Eustachian Valves on Stroke: A Scoping Review and Meta-Analysis

BACKGROUND

The role of Chiari network (CN) and Eustachian valves (EVs) in cardioembolic strokes is still unclear. There is inconsistency in the literature regarding clinical approach to these lesions to reduce stroke risk. We aimed to describe clinical presentation, neuroimaging and cardioimaging features, as well as management approaches for CN and EV in stroke context.

REVIEW SUMMARY

A systemic search was carried out using PubMed and Web of Science following PRISMA guidelines, Supplemental Digital Content 1 ( http://links.lww.com/NRL/A123 ). We retrieved 4 case-control studies, 2 cross sectional studies as well 8 case reports, with a total of 883 patients with a mean age of 44.6 years (±13.8). The combined prevalence of EV/CN in stroke-related patent foramen ovale (PFO) patients was 50% (95% CI: 31-68). With isolated prevalence for EV and CN of 43% (95% CI: 25-63), 18% (95% CI: 12-25), respectively. Patients with history of stroke had higher prevalence of EV/CN compared with controls odds ratio=2.45 (95% CI: 1.2-5, P <0.01). All case-control and cross-sectional studies defined EV/CN by transesophageal echocardiography or intracardiac cardiography. In the 8 case reports, 7 cases were diagnosed by transesophageal echocardiography, while only 1 case was diagnosed postmortem.

CONCLUSION

EV/CN are relatively common findings in stroke patients with PFO. While it appears that presence of EV/CN with a PFO increases the risk of cardioembolic stroke, they remain underrecognized. EV/CN should be considered as high-risk PFO features. There is a scarcity of research emphasizing their role in clinical decision making, especially PFO closure and antithrombotic therapy choice.

Cerebrovascular Events in Older Patients With Patent Foramen Ovale: Current Status and Future Perspectives

Patent foramen ovale (PFO) closure, along with medical therapy, has emerged as the therapeutic gold standard in younger (<60-year-old) patients with a PFO-related stroke for preventing recurrent events. However, PFO management guidelines lack definite recommendations for older (>60 years) patients with a PFO-related cerebrovascular event, a complex group of patients who were mostly excluded from PFO closure clinical trials. Nevertheless, several studies have shown a higher prevalence of PFO among older patients with cryptogenic stroke, and its presence has been associated with an increased risk of recurrent events. Furthermore, older patients exhibit a higher prevalence of high-risk PFO anatomical features, present inherent age-related risk factors that might increase the risk of paradoxical embolism through a PFO, and have a higher incidence of ischemic events after a PFO-related event. Additionally, observational studies have shown the safety and preliminary efficacy of PFO closure in older PFO-related stroke patients. Yet, higher rates of recurrent cerebrovascular events and new-onset atrial fibrillation were observed in some studies among older patients compared to their younger counterparts. After careful case-by-case evaluation, including the assessment of hidden potential cardioembolic sources of a cryptogenic stroke other than PFO, transcatheter PFO closure might be a safe and effective therapeutic option for preventing recurrent thromboembolic events in patients >60 years with a high-risk PFO-associated stroke. Ongoing trials will provide important insights into the role of PFO closure in the elderly population.

Pitfalls of Using Imaging Technique in the Presence of Eustachian Valve or Chiari Network: Effects on Right-to-Left Shunt and Related Influencing Factors

When patent foramen ovale (PFO) combines with the prominent Eustachian valve or Chiari network (EV/CN), contrast transthoracic echocardiography (cTTE) may miss the diagnosis of PFO. We sought to determine the characteristics of right-to-left shunt (RLS) in PFO patients with prominent EV/CN on cTTE and identify the causal factors of missed diagnosis. We consecutively enrolled 98 patients who suffered from PFO-related stroke and with prominent EV/CN. All patients were divided into the delayed and non-delayed groups according to the characteristics of RLS on cTTE. The characteristics of RLS were compared with those of 42 intrapulmonary shunt patients. The anatomical characteristics of PFO and EV/CN were analyzed in the 98 PFO patients. Upon cTTE, significantly delayed occurrence and longer duration of the RLS in the delayed group were found both at rest and during the Valsalva maneuver, similar to the intrapulmonary shunt. Multivariate logistic analysis revealed that the length of EV/CN (>19 mm) and the diameter of PFO at the left atrium aspect (<1.2 mm) were high-risk factors for missed diagnosis. In conclusion, RLS showed delayed emergence and disappearance in some of the PFO patients with prominent EV/CN. The length of EV/CN and the diameter of PFO may have been related to the missed diagnosis of PFO.

Platypnea Orthodeoxia Syndrome and Patent Foramen Ovale Closure: Single-Centre Experience and Long-Term Follow-Up

INTRODUCTION

Platypnea orthodeoxia syndrome (POS) is an uncommon condition characterised by dyspnoea and arterial desaturation induced by an upright position and relieved in the supine position, usually due to a patent foramen ovale (PFO). Percutaneous closure of a PFO is the preferred treatment to cure POS. This study aimed to evaluate the clinical and gasometrical characteristics and to describe the long-term outcomes of percutaneous PFO closure in a group of patients with POS.

METHODS

Patients with POS and a PFO treated by percutaneous intervention from 2010-2020 were reviewed. The primary efficacy outcome was the arterial oxygen pressure to fraction of inspired oxygen (PaO2/FiO2) ratio before and 24 hours after the procedure. Total clinical success was considered if the arterial oxygen saturation measured by pulse oximetry (SpO2) improved to >94% in the supine and sitting positions without supplemental oxygen, while partial success was considered if SpO2 improved from baseline but still required oxygen to achieve >94%. Secondary outcomes were an absolute improvement in SpO2 and sense of dyspnoea, without significant residual shunt on transthoracic echocardiography (TTE) at follow-up.

RESULTS

Of 168 patients undergoing PFO or atrial septal defect closure, 14 had POS (8.3%). Percutaneous PFO closure was successfully performed in all patients with a single device. Twelve of 14 patients had total clinical success (86%) and one patient had partial success. The PaO2/FiO2 ratio increased from 155.9±50.6 to 318.3±73.4 after PFO closure (p=0.002). All patients with total clinical success had a successful secondary efficacy outcome with an absolute improvement in SpO2 and complete resolution of dyspnoea, which was maintained at follow-up (37±20 months; range, 11 months to 6 years). None had a significant residual shunt between 12 and 24 months of follow-up.

CONCLUSION

The PFO percutaneous closure was a successful, durable and safe method for patients presenting with POS; it achieved major improvements in both gasometrical parameters and quality of life.

Advances in the management of cardioembolic stroke associated with patent foramen ovale

Patent foramen ovale (PFO) describes a valve in the interatrial septum that permits shunting of blood or thrombotic material between the atria. PFOs are present in approximately 25% of the healthy population and are not associated with any pathology in the vast majority of cases. However, comparisons between patients with stroke and healthy controls suggest that PFOs may be causative of stroke in certain patients whose stroke is otherwise cryptogenic. Options for the diagnosis of PFO include transthoracic echocardiography, transesophageal echocardiography, and transcranial Doppler ultrasonography. PFOs associated with an interatrial septal aneurysm seem to be more strongly linked to risk of recurrent stroke. Therapeutic options for secondary stroke prevention in the setting of a PFO include antiplatelet therapy, anticoagulation, and percutaneous device closure. Recent randomized clinical trials suggest that percutaneous closure reduces the subsequent risk of stroke in appropriately selected patients, with a large relative benefit but small absolute benefit. Referral for percutaneous PFO closure should therefore be considered in certain patients after a multidisciplinary, patient centered discussion. Areas for future study include structural biomarkers to aid in determining the role of PFO closure in older people with possible PFO associated stroke, the role of direct oral anticoagulants, and very long term outcomes after device closure.

Stroke in patients with secundum atrial septal defect and sequelae after transcatheter closure

OBJECTIVE

To evaluate the frequency of and risk factors for stroke as a presenting feature in adult patients with secundum atrial septal defect (ASD); rates of post-closure atrial fibrillation (AF) and stroke were also assessed.

METHODS

We retrospectively reviewed adult patients who presented with an ASD between 2002 and 2018, excluding those with known atrial arrhythmias. Risk factors for stroke were identified using multivariable logistic regression. Post-closure stroke was evaluated using survival analysis stratified by the presence of post-procedure AF.

RESULTS

Of 346 patients with ASD (median age 44 years), 34 (10%) presented with a history of stroke. Independent risk factors included elevated body mass index over 25 (OR: 18.2; 95% CI: 4.0 to 82.2; p<0.001), smoking (OR: 9.5; 95% CI: 3.8 to 23.9; p<0.001) and a prominent Eustachian valve (OR: 9.2; 95% CI: 3.4 to 25.2; p<0.001). A scoring system based on these three parameters provided robust stroke risk stratification. During a median follow-up of 12 months after closure, 12 patients (4%) experienced AF and 4 patients (1%) had a new stroke. AF was highly associated with development of stroke post-closure (p<0.001).

CONCLUSIONS

In this study population, the incidence of stroke prior to ASD closure among patients without atrial arrhythmias was 10%. Risk factors included obesity, smoking and prominent Eustachian valve anatomy. Lifestyle changes should be recommended for at-risk patients, and it may be reasonable to consider ASD closure in the absence of haemodynamic indications in patients at increased risk of stroke.