Ssenabulya Francis R, Chothia Mogamat-Yazied
Division of Nephrology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
J Coll Med S Afr. 2025 Apr 30;3(1):110. doi: 10.4102/jcmsa.v3i1.110. eCollection 2025.
Hyperkalaemia is a common electrolyte disorder in hospitalised patients and is associated with fatal cardiac arrhythmias. In sub-Saharan Africa, there is a paucity of data regarding the prevalence and type of electrocardiographic (ECG) changes in patients who have hyperkalaemia.
A retrospective descriptive study was conducted at Tygerberg Hospital over a one-year period in 2019. Adult patients with hyperkalaemia of ≥ 5.5 mmol/L and associated ECG changes 3 h before or after documented laboratory hyperkalaemia were included. Spearman correlation coefficients and multilinear regression were used to identify correlations and associations, respectively, between serum potassium concentrations ([K]) and various ECG changes.
Of 344 patients who had hyperkalaemia and an associated ECG, 55% had ECG changes. These patients were older (60 years vs. 53 years, = 0.01), male (57% vs. 43%, < 0.01) and had more frequent kidney disease (88% vs. 78%, = 0.02). Statistically significant differences in all ECG measurements were present, except for wave amplitude. The most frequent ECG alterations were -wave abnormalities (52%) and peaked waves (45%). A weak-to-moderate correlation was present for the number of ECG changes and the [K]. The QRS duration (: 0.0076, < 0.001), PR interval (: 0.0039, < 0.001) and wave duration (: -0.0056, < 0.01) were associated with the [K].
The overall prevalence of ECG changes due to hyperkalaemia was only 55%.
It is essential for clinicians to recognise that the ECG changes during hyperkalaemia may have limited screening value.
