Complete atrioventricular block after arsenic trioxide treatment in an acute promyelocytic leukemic patient

AV block after arsenic trioxide (As2O3) treatment for refractory acute prom yelocytic leukemia is very rare, In this patient, the block was at A-H leve l and manifested with complete AV block and Wenckebach second-degree type 3 :2 block. The junctional recovery time during complete AV block did not sig nificantly prolong after administration of more arsenic trioxide. The effec t of heart block of arsenic trioxide seemed reversible after the discontinu ation of arsenic trioxide and was not correlated to the leukemic status as observed in this patient.