Symptomatic Bradycardia in a Hyperkalemic Patient: A Case Report
Author : A. Halimi, Y. Pintaningrum
Upload Date : 19-04-2018
Introduction: Bradycardia and hyperkalemia are commonly seen in the emergency department and are often life-threatening. Hyperkalemia can suppress or block electrical conduction of the heart, leading to bradycardia, although the severity is not always correlated.
Case Illustration: A 60-year old woman came with complaints of breathlessness, dizziness, and palpitations. Patient had a history of hypertension, diabetes mellitus, and percutaneous coronary intervention. From physical examination, blood pressure was 120/60 mmHg, heart rate was 35 beats/min, respiratory rate 18x/min, temperature 36.70C, oxygen saturation 96%. Electrocardiography result showed sinus bradycardia, 35 beats per minute with complete left bundle branch block. Laboratory examination revealed serum potassium of 8.1 mEq/L. Echocardiography result showed ejection fraction of 40%. Patient was diagnosed with symptomatic bradycardia, hyperkalemia, type 2 diabetes mellitus, diabetic nephropathy, and hypertensive heart disease. Patient was treated with an infusion of 5% dextrose, 40% dextrose and insulin injections, calcium gluconate injections, furosemide injections, and temporary pacemaker was implanted.
Discussion: Bradycardia with broad QRS complex and flattening of P waves occurred in this patient, that was suggestive of hyperkalemia. Potassium has been known to affect heart function through its role in myocardial action potential. Hyperkalemia causes decreased resting membrane potential, decreased myocardial conduction velocity, and increased repolarization rate. Hypokalemia and hyperkalemia can lead to fatal arrhythmias, and eventually death. In this case, insulin injection was given to shift circulating potassium to intracellular compartment, furosemide to eliminate potassium from the body, and calcium gluconate to stabilize the myocardium. ACE inhibitors, ARBs, and potassium-sparing diuretics should be stopped. The electrocardiogram showed some improvement after temporary pacemaker implantation and sinus rhythm is seen on the third day of hospitalization.
Conclusion: A case of symptomatic bradycardia caused by hyperkalemia was presented. If history, physical examination, and ECG findings are suggestive of life-threatening hyperkalemia, treatment can be given while waiting for laboratory results.
KEYWORDS : bradycardia, hyperkalemia