Severe Hypokalemia ECG Changes Mimicking Those of Acute Coronary Syndrome (ACS) in Patient with Underlying Ischaemic Heart Disease: A Case Review

Abstract

Background: Hypokalemia is seen on regular basis in medical emergency. The definition of hypokalemia is serum potassium level below 3.5 mmol/L, meanwhile severe hypokalemia is serum potassium level below 2.5 mmol/L [1]. Patient with hypokalemia can present with wide range of presentation including musculoskeletal complaints from numbness to acute paralysis. Severe hypokalemia has tendency to progress to intestinal paralysis and respiratory failure. In some cases of hypokalemia, cardiovascular system can also be affected causing cardiac arrhythmias and heart failure [2]. Aim: This case report is to highlight that severe hypokalaemia can present with ECG changes mimicking acute coronary syndrome (ACS) which was fully resolved with correction of potassium level. Methods: We report a case of 84 years old Chinese man with underlying triple vessel disease presented with generalised body weakness for 2 days. ECG on arrival noted changes suggestive of ACS with ST segment depression in lead V4-V6 with first degree heart block, however patient had no ischemic symptoms and the potassium level was severe low at 1.6 mmol/L (3.5 - 5.1 mmol/L). He was correctly not treated for ACS. Outcomes: Repeated ECG post fast intravenous potassium correction noted complete resolution of the ST segment depression and first degree heart block. Patient discharged well from hospital four days later with potassium level of 3.8 mmol/L. Conclusions: Severe hypokalemia with asymptomatic ECG of ACS changes can safely be treated as a single entity clinical emergency with good resolution and no complication after normalizing potassium level.