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Valproic Acid as a Cause of Transient Atrio-Ventricular Conduction Block Episodes.
Vedat Davutoglu1, Munife Neyal2, Gokhan Altunbas1
1Gaziantep University, Department of Cardiology.
Journal of Atrial Fibrillation
|December 19, 2017
Summary
Valproic acid can rarely cause symptomatic atrio-ventricular block, even at normal levels. Investigate this side effect and consider dose reduction before pacemaker implantation.
Area of Science:
- Cardiology
- Neurology
- Pharmacology
Background:
- Valproic acid is a widely used antiepileptic and mood-stabilizing drug.
- Atrio-ventricular (AV) block is a rare but serious cardiac conduction abnormality.
Observation:
- A case study detailing a patient experiencing symptomatic atrio-ventricular conduction block episodes.
- Monitoring revealed these episodes occurred despite the patient maintaining normal therapeutic blood levels of valproic acid.
Findings:
- Symptomatic atrio-ventricular block is identified as a potential, albeit unusual, side effect of valproic acid.
- The cardiac complication was observed even when valproic acid levels were within the normal therapeutic range.
Implications:
- Clinicians should consider valproic acid-induced AV block in patients presenting with these symptoms.
- Before resorting to invasive procedures like pacemaker implantation, investigating and potentially reducing the valproic acid dosage is recommended.
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