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Chronic hydroxychloroquine use associated with QT prolongation and refractory ventricular arrhythmia
Chun-Yu Chen1, Feng-Lin Wang, Chih-Chuan Lin
1Department of Emergency Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan.
Clinical Toxicology (Philadelphia, Pa.)
|April 18, 2006
Summary
Chronic hydroxychloroquine (HCQ) use can lead to dangerous heart rhythm problems like torsade de pointes. This case highlights the cardiac risks associated with long-term HCQ therapy for lupus erythematosus.
Area of Science:
- Cardiology
- Rheumatology
- Pharmacology
Background:
- Hydroxychloroquine (HCQ) is a common treatment for lupus erythematosus.
- Cardiac toxicity of HCQ has predominantly focused on acute overdose scenarios.
- The potential for chronic HCQ use to induce cardiac arrhythmias remains less understood.
Observation:
- A 67-year-old female with lupus erythematosus on chronic HCQ therapy presented with acquired long QT interval syndrome.
- She experienced refractory ventricular arrhythmia diagnosed as Torsades de Pointes.
- Other causes of long QT syndrome were excluded, implicating HCQ.
Findings:
- Discontinuation of HCQ led to QT interval shortening.
- The patient's ventricular tachycardia resolved after HCQ cessation and medical treatment.
- This case demonstrates a link between chronic therapeutic HCQ use and potentially lethal cardiac arrhythmias.
Implications:
- Healthcare providers should consider the risk of cardiac arrhythmias with long-term hydroxychloroquine use.
- Balancing the benefits of HCQ in rheumatic diseases against cardiac risks is crucial.
- Further research into the mechanisms of chronic HCQ cardiotoxicity is warranted.
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