Presence of Atrial Fibrillation in Stroke Patients With Patent Foramen Ovale: Systematic Review and Meta-Analysis

Prevalence and characteristics of patent foramen ovale in a sample of Egyptian population: a computed tomography study

BACKGROUND

The reported prevalence of patent foramen ovale (PFO) in the general population is variable. It ranges between 8.6 and 42% according to the population studied and the imaging technique used. We aim to prospectively assess the prevalence and characteristics of PFO and interatrial septum (IAS) abnormalities as well as the related clinical manifestations in a sample of Egyptian population.

RESULTS

This study comprised 1000 patients who were referred for CT coronary angiography (CTCA). Mean age was 52.5 ± 10.9 years. The prevalence of PFO among the studied population was 16.3%; closed PFO (grade I) 44.2%, open PFO (grade II) 50.9%, and open PFO with jet (grade III) 4.9%. Anatomical high-risk PFO features-defined as the presence of at least 2 or more of the following (diameter ≥ 2 mm, length ≥ 10 mm, septal aneurysm "ASA", or redundant septum)-were found in 51.5% of PFOs' population. Other IAS abnormalities as redundant septum (8.6%), ASA (5.3%), Bachmann's bundle (4.5%), microaneurysm (2.6%), and atrial septal defect (ASD) (0.4%) were detected. There was a lower rate of coexistence of ASA with PFO (p = 0.031). Syncope was significantly higher in patients with PFO compared to those without PFO (6.7% vs. 1.6%, p = 0.001). Stroke, transient ischaemic attacks (TIA), and dizziness were similar in both groups. TIA, dizziness, and syncope were significantly higher in patients with IAS abnormalities including PFO compared to those without IAS abnormalities. Syncope was also significantly higher in PFO with high-risk anatomical features compared to those with non-high-risk PFO population (p = 0.02).

CONCLUSION

The prevalence of PFO in our study was approximately 16.3%, almost half of them showed anatomical high-risk features for stroke. Dizziness, syncope and TIA were significantly higher in patients with IAS abnormalities including PFO.

Monitoring for atrial fibrillation prior to patent foramen ovale closure after cryptogenic stroke

BACKGROUND

Patients who had a cryptogenic stroke (CS) suspected to be causally related to a patent foramen ovale (PFO) are candidates for percutaneous PFO closure. In such patients, it is important to screen for atrial fibrillation (AF). Limited guidance is available regarding AF monitoring strategies in CS patients with PFO addressing optimal monitoring technology and duration.

AIM

To provide a narrative review of cardiac rhythm monitoring in CS patients considered for PFO closure, including current practices, stroke recurrences after CS, findings from monitoring studies in CS patients, and predictors for AF detection published in the literature. To propose a personalized strategy for cardiac monitoring in CS patients, accounting for aspects predicting AF detection.

SUMMARY OF REVIEW

AF detection in CS patients is predicted by age, left atrial enlargement, prolonged PR interval, frequent premature atrial contractions, interatrial conduction block, diabetes, prior brain infarctions, leukoaraiosis, elevated B-type natriuretic peptide (BNP)/N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, and a family history of AF, as well as composed scores (e.g. CHA₂DS₂-VASc, atrial fibrillation in embolic stroke of undetermined source (AF-ESUS)). The causal role of the PFO may be accounted for by the risk of paradoxical embolism (RoPE) score and/or the PFO-Associated Stroke Causal Likelihood (PASCAL) classification.

CONCLUSION

A personalized approach to AF detection in CS patients is proposed, accounting for the likelihood of AF detection and aimed at obtaining sufficient confidence regarding the absence of AF in patients considered for PFO closure. In addition, the impact of high-risk PFO features on the monitoring strategy is discussed.

European Stroke Organisation (ESO) guideline on screening for subclinical atrial fibrillation after stroke or transient ischaemic attack of undetermined origin

We aimed to provide practical recommendations for the screening of subclinical atrial fibrillation (AF) in patients with ischaemic stroke or transient ischaemic attack (TIA) of undetermined origin. These guidelines are based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. Five relevant Population, Intervention, Comparator, Outcome questions were defined by a multidisciplinary module working group (MWG).

Longer duration of cardiac rhythm monitoring increases the detection of subclinical AF, but the optimal monitoring length is yet to be defined. We advise longer monitoring to increase the rate of anticoagulation, but whether longer monitoring improves clinical outcomes needs to be addressed. AF detection does not differ from in- or out-patient ECG-monitoring with similar monitoring duration, so we consider it reasonable to initiate in-hospital monitoring as soon as possible and continue with outpatient monitoring for more than 48h. Although insertable loop recorders (ILR) increase AF detection based on their longer monitoring duration, comparison with non-implantable ECG devices for similar monitoring time is lacking. We suggest the use of implantable devices, if feasible, for AF detection instead of non- implantable devices to increase the detection of subclinical AF. There is weak evidence of a useful role for blood, ECG, and brain imaging biomarkers for the identification of patients at high risk of AF. In patients with patent foramen ovale, we found insufficient evidence from RCT, but prolonged cardiac monitoring in patients >55 years is advisable for subclinical AF detection. To conclude, in adult patients with ischaemic stroke or TIA of undetermined origin, we recommend longer duration of cardiac rhythm monitoring of more than 48h and if feasible with IRL to increase the detection of subclinical AF.