“Tent-shaped” T waves of normal amplitude in potassium intoxication

Clinical and Biochemical Changes During Exchange Transfusion

“…Latent tetany in a group of adults with coexisting hypopotassaemia and hypocalcaemia was rendered manifest by the slow intravenous infusion of potassium salts even though the final plasma potassium level did not exceed the usual normal range (Engel et al, 1949). More recently Levine et al (1952) have claimed that hypocalcaemia may actually potentiate the electrocardiographic signs of hyperpotassaemia. None of these facts was con-firmed in this investigation.…”

A Clinical Correlative Study of the Electrocardiogram in Electrolyte Imbalance

“…Several authors 14 in particular have stressed the lack of conformity of electrocardiographic manifestations with the serum levels of potassium. This disparity has been attributed to the presence of electrocardiographic alterations from other causes or to concomitant abnormalities of other electrolytes.…”

“…There was, however, no consistency between the electrocardiographic alterations and absolute potassium or sodium concentrations, intracellular or extracellular. Changes in the autonomic nerve tone and pharmacologic actions of epinephrine, insulin, veratrine, and in particular quinidine, have been noted to simulate electrocardiographic patterns of hypokalemia.9 [11][12][13] It is also well known that pre-existent or concomitant alterations of the ST-T segment caused by heart strain, intraventricular block, digitalis medication, coronary disease, hypotension, and hypoxia may prevent, modify, or simulate changes induced by electrolyte imbalance.9' [14][15][16] In view of this multiplicity of factors acting upon the electrocardiogram in conjunction with, or in addition to, the effects of specific electrolyte derangements, an objective study in a diversified hospital population appeared worthwhile in order to gain some idea of the practical value and the limitations of electrocardiographic diagnosis of electrolyte imbalance. In this study special attention was directed to cases in which a correlation could not be made and to an analysis of the factors that conceivably may have contributed to the discrepancy between the chemical and electrocar- diographic findings.…”

Pseudoinfarction Pattern Associated with Electrolyte Disturbance

“…The electrocardiographic changes associated with hyperkalemia have been well documented by previous writers.1-4 These changes include (1) peaking of the Twaves; (2) increased depth of the S-wave, with lowering of the R-wave; (3) widening and then loss of P-waves; (4) ST-segment elevation associated with intraventricular conduction disturbances, resulting in a widened QRS complex; (5) prolongation of P-R interval, and (6) (Fig. 3) showed tall peaked T-waves in V3 and V« and somewhat lower but peaked T-waves in standard Leads I and II.…”