The clinical significance of hyperkalaemia-associated repolarization abnormalities in end-stage renal disease

Abstract

Background. Hyperkalaemia is a common potentially fatal complication of chronic kidney disease (CKD). It may manifest as electrocardiogram (ECG) changes, the earliest of which is T-wave 'tenting'. However, this occurs in less than half of episodes of hyperkalaemia. The aim of this study was to determine what other clinical features relate to the probability of T-wave tenting; and if there is a longer-term survival difference between patients who develop tenting and those who do not. Method. One hundred and forty-five patients with endstage renal disease who had standard 12-lead ECG and concurrent serum potassium measurement were enrolled. The presence of tenting and the ratio of the amplitude of the tallest precordial T-wave and R-wave were determined (T:R). Results. Tenting was as common in normal range serum potassium as hyperkalaemia (33 versus 31%) and less common than in left ventricular hypertrophy (44%). T:R was less sensitive (24 versus 33%) but more specific (85 versus 67%) than tenting at correctly identifying hyperkalaemia ≥6.0 mmol/L. Tenting became less common with increasing age. Dialysis patients were more likely to show increased T: R that pre-dialysis Stage 5 CKD. Elevated T:R was not associated with worse cardiovascular outcome but was associated with increased risk of sudden death over a mean follow-up of 3.8 years (hazard ratio = 8.3, P = 0.021). Conclusions. The reason for the variability in T-wave changes is not clear. The ratio of precordial T-wave to Rwave amplitude is a more specific measure than tenting but both are poorly sensitive at detecting hyperkalaemia. The greater risk for sudden death may represent a susceptibility to cardiac arrhythmia during repolarization.

Predictors of Outcome in Patients Presenting with Moderate to Severe Hyperkalemia

“…Our study verified that age was an independent predictor of mortality and odds of death increased by 5% for each year increase in age. Contrary to other studies [9,12,13,15], our findings suggested that presence of chronic kidney disease or level of creatinine did not predict survival independently, this may reflect that other indicators of worsening kidney function such as eGFR are better predictors of outcome than serum creatinine alone [13]. It was also important to note that the presence of shock or use of inotropic agents was not associated with increased risk of mortality in patients with hyperkalemia.…”

“…Although the condition is associated with a variety of clinical presentations, EKG manifestations of hyperkalemia are generally progressive and proportional to the serum K+ and ventricular arrhythmias may be the first EKG finding of hyperkalemia. Sometimes, however, normal EKG may be seen even with very high serum potassium levels [1][2][3]9]. The management of hyperkalemia also depends on an understanding of the underlying physiology, cause of hyperkalemia and plasma potassium levels.…”

Emerging Role of Calcium-Activated Potassium Channel in the Regulation of Cell Viability Following Potassium Ions Challenge in HEK293 Cells and Pharmacological Modulation

“…Disease progression and increased hearth mortality are observed in chronic kidney disease under hypokalemia or hyperkalemia conditions and these effects are gender and race dependent [6]. Severe nephropathy with renal interstitial fibrosis and ventricular hypertrophy are seen in human patients under hyperkalemia states [7,8]. …”

Electrocardiographic manifestations in patients with hyperkalemia of the Medical Clinic Service of the National Hospital in 2018

“…En la hiperpotasemia la onda T es típicamente elevada (>10 mm ó 1 mV), angosta, simétrica y en punta (picuda o aspecto de tienda de campaña), suele aparecer precozmente con niveles de Sin alteraciones Con alteraciones leve moderada severa 61% 39% 50% 50% 50% 50% potasio 5,5 mEq/L, sobre todo en las derivaciones precordiales izquierdas (21). Sin embargo, existe una predisposición individual para que este cambio en la onda T se manifieste en el ECG.…”