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Complete atrioventricular block secondary to lithium therapy.
Teruo Shiraki1, Kunihisa Kohno, Daiji Saito
1Department of Cardiology, National Hospital Organization, Iwakuni Clinic Center, Iwakuni, Japan. shiraki@iwakuni-nh.go.jp
Summary
Lithium therapy can cause severe heart rhythm problems like complete atrioventricular block, even at normal levels. Patients with existing heart conduction issues require extreme caution when using lithium.
Area of Science:
- Cardiology
- Pharmacology
- Electrophysiology
Background:
- Lithium is a common treatment for bipolar disorder.
- Adverse cardiovascular effects of lithium are well-documented, with sinus node dysfunction being most frequent.
- The impact of lithium on cardiac conduction requires further investigation.
Observation:
- A case of complete atrioventricular (AV) block with syncopal attacks is presented.
- The condition developed secondary to lithium therapy.
- Serum lithium levels were within or below the therapeutic range during syncopal episodes.
Findings:
- Complete atrioventricular (AV) block can occur as a rare but serious adverse effect of lithium.
- Lithium-induced AV block may necessitate permanent pacemaker implantation.
- The risk of severe AV block exists even when serum lithium levels are therapeutic.
Implications:
- Lithium should be administered with extreme caution in all patients.
- Particular vigilance is warranted for patients with pre-existing mild disturbances in AV conduction.
- Cardiovascular monitoring is crucial for patients on long-term lithium therapy.
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