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Adenosine Concentration in Patients With Neurally Mediated Syncope
Antonella Groppelli1, Michele Brignole1, Mohamed Chefrour2
1Cardiology Unit, Faint & Fall Programme, Department of Cardiology, IRCCS Istituto Auxologico Italiano, San Luca Hospital, Milan, Italy.
Frontiers in Cardiovascular Medicine
|July 8, 2022
Summary
Adenosine blood levels (ABL) differ between patients with neurally mediated syncope (NMS) and healthy individuals. Low and high ABL values are prevalent in NMS patients, aiding in diagnosis.
Area of Science:
- Cardiology
- Neurology
- Biochemistry
Background:
- Neurally mediated syncope (NMS) diagnosis can be challenging.
- Adenosine blood levels (ABL) may differentiate NMS subtypes.
- A rapid ABL measurement method is now available.
Purpose of the Study:
- Compare ABLs in patients with suspected NMS versus healthy controls.
- Determine the prevalence of low and high ABL in NMS patients.
Main Methods:
- Collected whole blood via finger puncture onto blot paper.
- Measured adenosine concentration using liquid chromatography/mass spectrometry (LC-MS/MS).
Main Results:
- Patients with syncope had higher median ABL (0.63 μM) than controls (0.54 μM).
- Low ABL (<0.40 μM) found in 19% of patients; high ABL (>0.80 μM) in 18% of patients.
- Significantly more patients than controls had low or high ABL values (p=0.003 and p=0.009, respectively).
Conclusions:
- Adenosine blood levels are significantly different in patients with suspected NMS compared to healthy subjects.
- Low and high ABL values are common in NMS patients, representing 19% and 18% respectively.
- ABL measurement can help define the purinergic profile for NMS diagnosis.
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