Correlation of Iatrogenic Mild Hyperkalaemia and Bradyarrhythmia: A Problem of Polypharmacy in Elderly

Mild hyperkalaemia does not typically cause  cardiac  symptoms.  However, for an elderly  patient  on atrio-ventricular (AV) nodal  blocker,  even  mild hyperkalaemia may result in disastrous  outcome. We report a case of persistent  bradyarrythmia caused  by iatrogenic  hyperkalaemia in a patient  who had concomitant use of AV nodal medication. An 81-year-old lady with multiple comorbidities and a long list  of  medications presented with  symptomatic bradyarrhythmia. She,  in fact,  had two AV nodal  blockers  in her prescription, a beta-blocker and  amiodarone. Her potassium  level was found to be mildly elevated  due  to acute  renal  failure. She remained bradycardic despite  initial treatment  and  was subsequently dependant on intravenous isoproterenol until her renal function improved.  This case highlights the different threshold  for manifestation of hyperkalaemic symptoms in a growing group of patients: elderly patients with multiple comorbidities and polypharmacy.