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Transient, high-grade atrioventricular block from high-dose cyclophosphamide
Nayan Agarwal1, Thomas A Burkart1
1Department of Cardiovascular Medicine, UF Health Shands Hospital, Gainesville, Florida 32608.
Texas Heart Institute Journal
|January 7, 2014
Summary
High-dose cyclophosphamide therapy can rarely cause high-grade atrioventricular block in stem cell transplant patients. Early cardiac evaluation is recommended before administering this chemotherapy agent.
Area of Science:
- Cardiology
- Oncology
- Pharmacology
Background:
- Cyclophosphamide is a key alkylating agent in stem cell transplantation, valued for its anticancer and myeloablative effects.
- Known cardiac complications include heart failure, pericarditis, and arrhythmias, but high-grade atrioventricular block is seldom reported.
Observation:
- A 71-year-old male patient developed high-grade atrioventricular block hours post-high-dose cyclophosphamide administration.
- The patient's condition resolved after temporary pacemaker insertion and cyclophosphamide discontinuation.
Findings:
- High-dose cyclophosphamide can precipitate high-grade atrioventricular block, a rare but serious cardiac adverse event.
- This cardiac complication appears reversible upon cessation of the drug and supportive care.
Implications:
- Pre-treatment cardiac screening for conduction abnormalities is crucial for patients receiving high-dose cyclophosphamide.
- Clinicians should consider cyclophosphamide as a potential cause of new-onset atrioventricular block in transplant recipients.
- Alternative chemotherapeutic agents may be considered for patients with pre-existing cardiac conduction issues.
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