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.