Hyperkalemia Presenting as Sinus Bradycardia, Junctional Rhythm and Atrial Bigeminy.

The spectrum of electrocardiographic changes seen with hyperkalemia is known to progress gradually with increasing serum levels of potassium. Initial changes are limited to peaked T waves and QT shortening, which subsequently progress to prolonged QRS/QT intervals, and finally sinus arrest, sinus bradycardia and asystole. We report a unique case of severe sinus bradycardia with atrial bigeminy and junctional rhythm in the setting of moderate hyperkalemia, a rarely reported electrocardiographic finding.