Irreversible sinus node dysfunction induced by resumption of lithium therapy
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Published on: December 11, 2017
1Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan.
Insights
Long-term lithium therapy can cause severe sinus node dysfunction, leading to syncope. This risk may be irreversible, necessitating pacemaker implantation even after lithium discontinuation.
Area of Science:
- Cardiology
- Pharmacology
- Electrophysiology
Background:
- Lithium is a mood stabilizer used for bipolar disorder.
- Sinus node dysfunction (SND) affects heart rhythm.
- Long-term lithium use has potential cardiac side effects.
Observation:
- A 56-year-old woman experienced syncope due to SND after prolonged lithium treatment.
- Her sinus node function recovered upon lithium cessation.
- SND recurred with low-dose lithium and became irreversible after subsequent discontinuation.
Findings:
- Lithium therapy can induce severe and potentially irreversible sinus node dysfunction.
- Prior recovery of sinus node function does not preclude irreversible damage upon lithium re-challenge.
- This case highlights a rare but serious risk associated with lithium treatment.
Implications:
- Clinicians should monitor for cardiac arrhythmias, particularly SND, in patients on long-term lithium.
- Irreversible SND is a potentially fatal complication requiring permanent pacemaker implantation.
- The risk of irreversible cardiac effects necessitates careful patient selection and monitoring during lithium therapy.
Abstract:
We present the case of a 56-year-old woman with syncope and sinus node dysfunction after long-term lithium therapy. Following lithium discontinuation, sinus node function recovered completely. After resuming low doses of lithium, however, severe sinus node dysfunction recurred. Thereafter, sinus node function did not recover after lithium was discontinued, and a permanent pacemaker was implanted. These findings suggest that irreversible sinus node dysfunction should be recognized as a potentially fatal, albeit rare, risk of lithium therapy, and that previous recovery from sinus node dysfunction after long-term lithium treatment cannot always guarantee the reversible nature of this abnormality after resumption of lithium therapy.
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