DISCUSSION
This study aimed to compare the clinical and echocardiographic characteristics of patients with migraine and ESUS who presented with a PFO. The findings of this research provide valuable insights into the potential relationships between these conditions, shedding light on their distinct cardiovascular characteristics and underlying mechanisms.
Transthoracic echocardiography is the initial non-invasive imaging technique used to assess cardiac structures. In cases where structural heart defects are suspected, 2D and color Doppler imaging provide crucial information, while contrast echocardiography and TEE may be necessary for a definitive diagnosis. Echogenicity issues encountered during TTE also contribute to false-positive evaluations. Therefore, obtaining 2D and color Doppler images from different windows and their complementary analysis are vital for an accurate diagnosis of PFO (16).
Patent Foramen Ovale is a common cardiac anomaly, present in a significant portion of the general population. Its diagnosis is of particular interest due to its potential implications for adverse clinical outcomes. While most PFOs remain asymptomatic, a fraction of cases are associated with paradoxical embolism, ESUS, and migraine. These associations have been previously established in the literature (17). The association between PFO and migraine remains uncertain, despite some studies suggesting a connection. Cao et al. conducted a study presenting neuroimaging evidence and novel insights into the correlation between PFO and migraine (18). Furthermore, an increased incidence of cerebrovascular events has been associated with a larger PFO size and a higher number of microbubbles passing through the shunt during echocardiography (19, 20).
The present study confirms and expands upon these associations, demonstrating that ESUS patients with PFO are older and more likely to have comorbidities such as diabetes and hypertension. In contrast, patients with Migraine and PFO exhibit a higher prevalence of active smoking. These differences in patient demographics suggest that distinct risk factors may be at play in the development of ESUS and Migraine in the presence of PFO.
The direction and magnitude of blood flow in patent foramen ovale (PFO) are influenced by factors such as defect size, compliance and pressures within the left and right atria and ventricles (21). The presence of the Eustachian valve is frequently observed in patients with PFO (22, 19) and is believed to increase the risk of paradoxical embolism by diverting blood from the inferior vena cava to the fossa ovalis region (23). In patients with PFO and right-to-left shunting, no changes in right atrial and ventricular volumes are expected. The echocardiographic evaluations performed in this study provide critical insights into the structural and functional characteristics of PFO in both patient groups. In ESUS patients, there was a higher prevalence of large microbubble passage through the interatrial septum, suggesting a more substantial right-to-left shunting of blood. This finding aligns with the increased risk of paradoxical embolism in ESUS patients. Additionally, ESUS patients exhibited longer PFO lengths, highlighting the potential role of PFO size in contributing to embolic events. These findings underscore the importance of assessing PFO morphology in the evaluation of patients with ESUS.
However, the PFO width was similar between the two patient groups, indicating that the width may not be a distinguishing factor in the development of ESUS or migraine. This highlights the importance of considering other structural and functional PFO characteristics, such as length and right-to-left shunt severity.
The study also assessed two scoring systems, the RoPe score and the High-risk PFO score, to identify high-risk PFO based on clinical and anatomical criteria. While the High-risk PFO score was higher in ESUS patients, it was statistically similar between the two groups. This suggests that the presence of high-risk criteria alone may not be sufficient to differentiate between ESUS and Migraine patients with PFO. The findings indicate the need for a comprehensive evaluation of PFO characteristics, including size, right-to-left shunt severity, and anatomical features, to better understand their role in clinical outcomes.
The results of this study have important clinical implications. Understanding the characteristics of PFO and its potential link to clinical conditions like migraine and ESUS is crucial for effective diagnosis and management. It also emphasizes the need for personalized treatment strategies based on the specific features of PFO in individual patients.
Future research in this field should continue to explore the mechanisms underlying PFO-related embolic events and migraines. Investigating the interplay between PFO characteristics and clinical outcomes will provide a foundation for developing targeted interventions and treatments. Moreover, large-scale, multicenter studies may help validate the findings of this single-center research, enhancing our understanding of these conditions.
In conclusion, this study contributes to our understanding of the relationship between PFO, Migraine, and ESUS by examining their clinical and echocardiographic characteristics. It underscores the need for a comprehensive evaluation of PFO morphology and its potential role in clinical outcomes, paving the way for more tailored approaches to patient management and treatment.
The present study has several limitations that should be considered when interpreting the findings. Firstly, this was an observational single-center study, which may limit the generalizability of the results to broader populations. Future multicenter studies are needed to validate and expand upon these findings. Additionally, the study population was relatively small, and the age range was limited to 18 to 60 years. This narrow age range may not fully capture the diversity of patients with PFO, Migraine, and ESUS, potentially excluding older or younger individuals who could also be affected. Moreover, this study primarily relied on echocardiographic assessments to evaluate PFO characteristics, and other diagnostic modalities were not employed, potentially limiting the comprehensiveness of the PFO characterization. The study also did not include long-term follow-up data to assess clinical outcomes related to PFO in Migraine and ESUS patients. A longer follow-up period would be valuable to determine the impact of PFO characteristics on the incidence of adverse clinical events. Lastly, the study’s focus was on identifying differences and associations, and it did not delve into the underlying mechanisms driving the observed disparities in PFO features and clinical characteristics between Migraine and ESUS patients. Further research is warranted to explore the underlying pathophysiological processes involved in these conditions and their relationship to PFO characteristics.