Extreme sinus bradycardia associated with lithium therapy

Area of Science:

• Cardiology
• Clinical Pharmacology

Background:

• Lithium is a mood stabilizer widely used in treating bipolar disorder.
• Adverse cardiac effects of lithium, though rare, necessitate careful monitoring.

Observation:

• A patient on lithium therapy presented with significant sinus bradycardia and electrocardiographic T wave abnormalities.
• Cardiac ischemia was ruled out through radionuclide imaging and exercise stress testing.

Findings:

• Electrocardiographic changes were directly attributed to lithium administration.
• An inverse correlation was observed between the patient's heart rate and plasma lithium concentration.

Implications:

• Clinicians should be aware of potential lithium-induced cardiac side effects.
• Monitoring plasma lithium levels is crucial for managing cardiac adverse events in patients undergoing lithium therapy.