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Lithium-induced sinus node dysfunction at therapeutic serum levels.
L K Singh1, S K Praharaj, S K Munda
1Department of Psychiatry, Pandit Jawaharlal Nehru Medical College, Raipur, Chhattisgarh, India. singhlokesh123@gmail.com
The National Medical Journal of India
|July 27, 2011
Summary
Lithium carbonate can cause sinus bradycardia even at therapeutic levels, a rare side effect. This cardiac issue resolved after stopping lithium and did not recur with valproate treatment.
Area of Science:
- Cardiology
- Pharmacology
- Psychiatry
Background:
- Lithium carbonate is a mood stabilizer used for bipolar disorder.
- Lithium-induced cardiotoxicity is typically associated with overdose.
- Cardiac adverse effects at therapeutic lithium levels are uncommon.
Observation:
- A patient on lithium carbonate developed sinus bradycardia.
- Serum lithium levels were within the therapeutic range during the event.
- The bradycardia resolved upon lithium discontinuation.
Findings:
- Lithium carbonate can induce sinus bradycardia even at therapeutic serum concentrations.
- Valproate treatment did not lead to recurrence of the bradycardia.
- This suggests a specific lithium-related cardiac effect.
Implications:
- Clinicians should monitor for cardiac side effects, including bradycardia, in patients treated with lithium carbonate, even within therapeutic ranges.
- This case highlights the importance of considering drug-induced cardiac events in patients presenting with bradycardia.
- Alternative mood stabilizers like valproate may be considered for patients experiencing lithium-induced cardiac adverse effects.
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