Transient trifascicular block in severe hyperkalemia: A case report

Abstract

Hyperkalemia is a commonly encountered electrolyte abnormality that can significantly alter normal 
cardiac conduction. Potentially lethal dysrhythmias associated with hyperkalemia include complete 
heart block and Mobitz type II second-degree atrioventricular (AV) block. We report a case of 
trifascicular block, due to hyperkalemia. The patient's symptoms and electrocardiogram (ECG) evidence 
of trifascicular block resolved with lowering of serum potassium levels, with subsequent ECG showing 
left anterior hemiblock. This paper highlights an infrequently reported dysrhythmia associated with 
hyperkalemia that emergency physicians should be familiar with.