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The Rabbit Blood-shunt Model for the Study of Acute and Late Sequelae of Subarachnoid Hemorrhage: Technical Aspects
Published on: October 2, 2014
Right-to-left shunt is common in chronic migraine
S J Nahas1, W B Young, R Terry
1Department of Neurology, Thomas Jefferson University Hospital, Philadelphia, PA, USA. stephanie.nahas@jefferson.edu
Cephalalgia : an International Journal of Headache
|September 8, 2009
Summary
Patients with chronic migraine (CM) have a significantly higher prevalence of right-to-left shunt (RtLS), a heart condition, compared to the general population. This finding suggests a potential link between RtLS and chronic migraine.
Area of Science:
- Neurology
- Cardiology
- Medical Diagnostics
Background:
- Right-to-left shunt (RtLS) prevalence is known in the general population and migraine patients without chronic migraine (CM).
- RtLS prevalence in CM, irrespective of aura, remains undetermined.
- Migraine with aura shows a higher RtLS prevalence (~50%) than migraine without aura (~20-35%).
Purpose of the Study:
- To ascertain the prevalence of RtLS in patients diagnosed with chronic migraine (CM).
- To investigate the correlation between RtLS presence and grade with aura, neurological symptoms, and disease characteristics in CM patients.
- To compare RtLS prevalence in CM patients against the general population and episodic migraine cohorts.
Main Methods:
- A cohort of 131 consecutive chronic migraine (CM) patients aged 18-60 years was studied.
- Patients underwent structured diagnostic interviews.
- Right-to-left shunt (RtLS) presence and grade were assessed using bubble transcranial Doppler with Valsalva maneuver.
Main Results:
- A significantly higher prevalence of RtLS was observed in CM patients (66%) compared to the general population and episodic migraine groups (P < 0.001).
- No significant difference in RtLS rate or grade was found between CM patients with and without aura.
- Headache features and neurological symptoms did not differ between CM patients with or without RtLS.
Conclusions:
- Patients with chronic migraine (CM), regardless of aura, exhibit a higher prevalence of right-to-left shunt (RtLS) than the general and episodic migraine populations.
- The clinical significance of this increased RtLS prevalence in CM requires further investigation.
- This study highlights a potential association between RtLS and chronic migraine, warranting further research into underlying mechanisms and clinical implications.
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