Electrocardiographic manifestations of hyperkalemia in hemodialysis patients.

This study was performed to evaluate whether any electrocardiogram (ECG) parameter can predict the presence of hyperkalemia in patients on maintenance hemodialysis (HD). In January 2006, we conducted a cross-sectional study of 80 stable patients with end-stage renal disease from four university-based HD units of Tehran, Iran, receiving conventional thrice-weekly HD. Pre-HD serum electrolyte values and conventional 12-lead ECG were obtained from each patient. Bivariate linear regression was used for assessing relationship of the study variables with hyperkalemia (K+ > 5.2 mg/dL). Multivariable logistic regression was used for evaluating independent relationship between decreased T wave duration (< or =170 ms) and other variables. Bivariate correlation analysis showed a significant inverse correlation between serum potassium concentration and T wave duration (P < 0.05). None of the patients with serum potassium of > or = 5.6 mg/dL had T wave duration >200 ms. Multivariate logistic analysis, after adjustment for other factors, also showed a significant relationship between decreased T wave duration (< or =170 ms) and hyperkalemia. We conclude that although hyperkalemia does not induce the usual ECG changes in HD patients, decreased T wave duration was found to be a good indicator of this lethal condition.