JACC Case Rep. 2026 May 20;31(20):107364. doi: 10.1016/j.jaccas.2026.107364. Epub 2026 Mar 16.
ABSTRACT
BACKGROUND: Brugada phenocopy is a reversible Brugada pattern on an electrocardiogram (ECG) caused by identifiable clinical conditions (such as fever, electrolyte abnormalities, or drug exposure) in patients without true congenital Brugada syndrome, which is an inherited arrhythmogenic disorder often associated with SCN5A mutations.
CASE SUMMARY: A 53-year-old man with metastatic myeloid sarcoma presented with high-grade fever and chest pain. He was previously treated with imatinib, discontinued because of severe skin rash, followed by dasatinib, and most recently avapritinib, initiated 3 weeks before presentation. The initial 12-lead ECG demonstrated a spontaneous type 1 Brugada pattern in leads V and V. Avapritinib was withheld, and Brugada ECG pattern resolved with defervescence. Genetic testing identified a heterozygous missense variant in the JPH2 gene.
DISCUSSION: We report a case of type 1 Brugada ECG pattern unmasked by febrile illness after avapritinib initiation, with an incidental finding of heterozygous missense variant in the JPH2 gene.
TAKE-HOME MESSAGE: This case introduces a previously unrecognized association between avapritinib and Brugada pattern and suggests avapritinib as a potential pharmacologic trigger in susceptible individuals.
PMID:42165456 | PMC:PMC13198151 | DOI:10.1016/j.jaccas.2026.107364