Irreversible sinus node dysfunction induced by resumption of lithium therapy

T Terao1, H Abe, K Abe

  • 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.

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